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  Subjects -> BIOLOGY (Total: 3211 journals)
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BIOLOGY (1536 journals)                  1 2 3 4 5 6 7 8 | Last

Showing 1 - 200 of 1720 Journals sorted alphabetically
AAPS Journal     Hybrid Journal   (Followers: 23)
Achievements in the Life Sciences     Open Access   (Followers: 5)
ACS Synthetic Biology     Hybrid Journal   (Followers: 25)
Acta Biologica Colombiana     Open Access   (Followers: 7)
Acta Biologica Hungarica     Full-text available via subscription   (Followers: 4)
Acta Biologica Sibirica     Open Access   (Followers: 2)
Acta Biologica Turcica     Open Access  
Acta Biomaterialia     Hybrid Journal   (Followers: 28)
Acta Biotheoretica     Hybrid Journal   (Followers: 4)
Acta Chiropterologica     Full-text available via subscription   (Followers: 6)
acta ethologica     Hybrid Journal   (Followers: 4)
Acta Fytotechnica et Zootechnica     Open Access   (Followers: 1)
Acta Limnologica Brasiliensia     Open Access   (Followers: 3)
Acta Médica Costarricense     Open Access   (Followers: 2)
Acta Musei Silesiae, Scientiae Naturales     Open Access  
Acta Neurobiologiae Experimentalis     Open Access  
Acta Parasitologica     Hybrid Journal   (Followers: 11)
Acta Scientiarum. Biological Sciences     Open Access   (Followers: 2)
Acta Scientifica Naturalis     Open Access   (Followers: 3)
Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis     Open Access   (Followers: 1)
Actualidades Biológicas     Open Access   (Followers: 1)
Advanced Health Care Technologies     Open Access   (Followers: 4)
Advanced Journal of Graduate Research     Open Access  
Advanced Nonlinear Studies     Hybrid Journal  
Advanced Studies in Biology     Open Access  
Advances in Antiviral Drug Design     Full-text available via subscription   (Followers: 2)
Advances in Bioinformatics     Open Access   (Followers: 17)
Advances in Biological Regulation     Hybrid Journal   (Followers: 4)
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Advances in Biosensors and Bioelectronics     Open Access   (Followers: 7)
Advances in Cell Biology/ Medical Journal of Cell Biology     Open Access   (Followers: 26)
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Advances in DNA Sequence-Specific Agents     Full-text available via subscription   (Followers: 7)
Advances in Ecological Research     Full-text available via subscription   (Followers: 44)
Advances in Environmental Sciences - International Journal of the Bioflux Society     Open Access   (Followers: 16)
Advances in Enzyme Research     Open Access   (Followers: 10)
Advances in Experimental Biology     Full-text available via subscription   (Followers: 8)
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Advances in Human Biology     Open Access   (Followers: 4)
Advances in Life Science and Technology     Open Access   (Followers: 18)
Advances in Life Sciences     Open Access   (Followers: 6)
Advances in Marine Biology     Full-text available via subscription   (Followers: 18)
Advances in Molecular and Cell Biology     Full-text available via subscription   (Followers: 23)
Advances in Organ Biology     Full-text available via subscription   (Followers: 2)
Advances in Planar Lipid Bilayers and Liposomes     Full-text available via subscription   (Followers: 3)
Advances in Regenerative Biology     Open Access   (Followers: 1)
Advances in Space Biology and Medicine     Full-text available via subscription   (Followers: 6)
Advances in Structural Biology     Full-text available via subscription   (Followers: 5)
Advances in Tropical Biodiversity and Environmental Sciences     Open Access  
Advances in Virus Research     Full-text available via subscription   (Followers: 5)
African Journal of Range & Forage Science     Hybrid Journal   (Followers: 8)
AFRREV STECH : An International Journal of Science and Technology     Open Access   (Followers: 1)
Ageing Research Reviews     Hybrid Journal   (Followers: 11)
Aging Cell     Open Access   (Followers: 21)
Agrokémia és Talajtan     Full-text available via subscription   (Followers: 2)
Agrokreatif Jurnal Ilmiah Pengabdian kepada Masyarakat     Open Access  
AJP Cell Physiology     Hybrid Journal   (Followers: 18)
AJP Endocrinology and Metabolism     Hybrid Journal   (Followers: 24)
AJP Lung Cellular and Molecular Physiology     Hybrid Journal   (Followers: 3)
Al-Kauniyah : Jurnal Biologi     Open Access  
Alasbimn Journal     Open Access   (Followers: 1)
Alces : A Journal Devoted to the Biology and Management of Moose     Open Access  
AMB Express     Open Access   (Followers: 1)
Ambix     Hybrid Journal   (Followers: 3)
American Biology Teacher     Full-text available via subscription   (Followers: 14)
American Fern Journal     Full-text available via subscription   (Followers: 1)
American Journal of Agricultural and Biological Sciences     Open Access   (Followers: 8)
American Journal of Bioethics     Hybrid Journal   (Followers: 13)
American Journal of Human Biology     Hybrid Journal   (Followers: 15)
American Journal of Medical and Biological Research     Open Access   (Followers: 8)
American Journal of Plant Sciences     Open Access   (Followers: 19)
American Journal of Primatology     Hybrid Journal   (Followers: 16)
American Malacological Bulletin     Full-text available via subscription   (Followers: 3)
American Naturalist     Full-text available via subscription   (Followers: 76)
Amphibia-Reptilia     Hybrid Journal   (Followers: 6)
Anadol University Journal of Science and Technology B : Theoritical Sciences     Open Access  
Anadolu University Journal of Science and Technology : C Life Sciences and Biotechnology     Open Access  
Anaerobe     Hybrid Journal   (Followers: 4)
Analytical Methods     Full-text available via subscription   (Followers: 11)
Anatomical Science International     Hybrid Journal   (Followers: 3)
Animal Cells and Systems     Hybrid Journal   (Followers: 4)
Animal Models and Experimental Medicine     Open Access  
Annales de Limnologie - International Journal of Limnology     Hybrid Journal   (Followers: 1)
Annales françaises d'Oto-rhino-laryngologie et de Pathologie Cervico-faciale     Full-text available via subscription   (Followers: 3)
Annales Henri Poincaré     Hybrid Journal   (Followers: 3)
Annals of Applied Biology     Hybrid Journal   (Followers: 7)
Annals of Biomedical Engineering     Hybrid Journal   (Followers: 17)
Annals of Human Biology     Hybrid Journal   (Followers: 5)
Annals of Science and Technology     Open Access  
Annual Review of Biomedical Engineering     Full-text available via subscription   (Followers: 13)
Annual Review of Biophysics     Full-text available via subscription   (Followers: 24)
Annual Review of Cancer Biology     Full-text available via subscription   (Followers: 1)
Annual Review of Cell and Developmental Biology     Full-text available via subscription   (Followers: 37)
Annual Review of Food Science and Technology     Full-text available via subscription   (Followers: 14)
Annual Review of Genomics and Human Genetics     Full-text available via subscription   (Followers: 25)
Annual Review of Phytopathology     Full-text available via subscription   (Followers: 12)
Anthropological Review     Open Access   (Followers: 23)
Anti-Infective Agents     Hybrid Journal   (Followers: 3)
Antibiotics     Open Access   (Followers: 9)
Antioxidants     Open Access   (Followers: 4)
Antioxidants & Redox Signaling     Hybrid Journal   (Followers: 8)
Antonie van Leeuwenhoek     Hybrid Journal   (Followers: 5)
Anzeiger für Schädlingskunde     Hybrid Journal   (Followers: 1)
Apidologie     Hybrid Journal   (Followers: 4)
Apmis     Hybrid Journal   (Followers: 1)
APOPTOSIS     Hybrid Journal   (Followers: 9)
Applied Biology     Open Access  
Applied Bionics and Biomechanics     Open Access   (Followers: 7)
Applied Vegetation Science     Full-text available via subscription   (Followers: 10)
Aquaculture Environment Interactions     Open Access   (Followers: 4)
Aquaculture International     Hybrid Journal   (Followers: 26)
Aquaculture Reports     Open Access   (Followers: 3)
Aquaculture, Aquarium, Conservation & Legislation - International Journal of the Bioflux Society     Open Access   (Followers: 7)
Aquatic Biology     Open Access   (Followers: 6)
Aquatic Ecology     Hybrid Journal   (Followers: 36)
Aquatic Ecosystem Health & Management     Hybrid Journal   (Followers: 15)
Aquatic Science and Technology     Open Access   (Followers: 3)
Aquatic Toxicology     Hybrid Journal   (Followers: 23)
Archaea     Open Access   (Followers: 3)
Archiv für Molluskenkunde: International Journal of Malacology     Full-text available via subscription   (Followers: 3)
Archives of Biological Sciences     Open Access  
Archives of Microbiology     Hybrid Journal   (Followers: 9)
Archives of Natural History     Hybrid Journal   (Followers: 7)
Archives of Oral Biology     Hybrid Journal   (Followers: 3)
Archives of Virology     Hybrid Journal   (Followers: 5)
Archivum Immunologiae et Therapiae Experimentalis     Hybrid Journal   (Followers: 2)
Arid Ecosystems     Hybrid Journal   (Followers: 2)
Arquivos do Instituto Biológico     Open Access   (Followers: 1)
Arquivos do Museu Dinâmico Interdisciplinar     Open Access  
Arthropod Structure & Development     Hybrid Journal   (Followers: 2)
Arthropods     Open Access   (Followers: 1)
Artificial DNA: PNA & XNA     Hybrid Journal   (Followers: 3)
Asian Bioethics Review     Full-text available via subscription   (Followers: 3)
Asian Journal of Biodiversity     Open Access   (Followers: 4)
Asian Journal of Biological Sciences     Open Access   (Followers: 3)
Asian Journal of Cell Biology     Open Access   (Followers: 5)
Asian Journal of Developmental Biology     Open Access   (Followers: 2)
Asian Journal of Medical and Biological Research     Open Access   (Followers: 4)
Asian Journal of Nematology     Open Access   (Followers: 4)
Asian Journal of Poultry Science     Open Access   (Followers: 4)
Atti della Accademia Peloritana dei Pericolanti - Classe di Scienze Medico-Biologiche     Open Access  
Australian Life Scientist     Full-text available via subscription   (Followers: 2)
Australian Mammalogy     Hybrid Journal   (Followers: 7)
Autophagy     Hybrid Journal   (Followers: 3)
Avian Biology Research     Full-text available via subscription   (Followers: 4)
Avian Conservation and Ecology     Open Access   (Followers: 11)
Bacteriology Journal     Open Access   (Followers: 1)
Bacteriophage     Full-text available via subscription   (Followers: 3)
Bangladesh Journal of Bioethics     Open Access  
Bangladesh Journal of Plant Taxonomy     Open Access  
Bangladesh Journal of Scientific Research     Open Access   (Followers: 1)
Batman Üniversitesi Yaşam Bilimleri Dergisi     Open Access  
Berita Biologi     Open Access   (Followers: 1)
Between the Species     Open Access   (Followers: 1)
Bio Tribune Magazine     Hybrid Journal  
BIO Web of Conferences     Open Access  
BIO-Complexity     Open Access  
Bio-Grafía. Escritos sobre la Biología y su enseñanza     Open Access  
Bioanalytical Reviews     Hybrid Journal   (Followers: 2)
Biocatalysis and Biotransformation     Hybrid Journal   (Followers: 6)
BioCentury Innovations     Full-text available via subscription   (Followers: 1)
Biochemistry and Cell Biology     Hybrid Journal   (Followers: 16)
Biochimie     Hybrid Journal   (Followers: 7)
BioControl     Hybrid Journal   (Followers: 5)
Biocontrol Science and Technology     Hybrid Journal   (Followers: 5)
Biodemography and Social Biology     Hybrid Journal  
BioDiscovery     Open Access   (Followers: 2)
Biodiversidade e Conservação Marinha : Revista CEPSUL     Open Access  
Biodiversitas : Journal of Biological Diversity     Open Access  
Biodiversity Data Journal     Open Access   (Followers: 4)
Biodiversity Informatics     Open Access   (Followers: 1)
Biodiversity Information Science and Standards     Open Access  
Biodiversity: Research and Conservation     Open Access   (Followers: 27)
Bioedukasi : Jurnal Pendidikan Biologi FKIP UM Metro     Open Access  
Bioeksperimen : Jurnal Penelitian Biologi     Open Access  
Bioelectrochemistry     Hybrid Journal   (Followers: 2)
Bioelectromagnetics     Hybrid Journal   (Followers: 1)
Bioenergy Research     Hybrid Journal   (Followers: 3)
Bioengineering and Bioscience     Open Access   (Followers: 1)
BioEssays     Hybrid Journal   (Followers: 10)
Bioethics     Hybrid Journal   (Followers: 15)
BioéthiqueOnline     Open Access  
Biofabrication     Hybrid Journal   (Followers: 5)
Biofilms     Full-text available via subscription   (Followers: 1)
Biogeosciences (BG)     Open Access   (Followers: 9)
Biogeosciences Discussions (BGD)     Open Access   (Followers: 2)
Bioinformatics     Hybrid Journal   (Followers: 330)
Bioinformatics and Biology Insights     Open Access   (Followers: 11)
Bioinspiration & Biomimetics     Hybrid Journal   (Followers: 7)
Biointerphases     Open Access   (Followers: 1)
Biojournal of Science and Technology     Open Access  
BioLink : Jurnal Biologi Lingkungan, Industri, Kesehatan     Open Access   (Followers: 1)
Biologia     Hybrid Journal  
Biologia on-line : Revista de divulgació de la Facultat de Biologia     Open Access  
Biological Bulletin     Partially Free   (Followers: 6)
Biological Control     Hybrid Journal   (Followers: 4)
Biological Invasions     Hybrid Journal   (Followers: 22)
Biological Journal of the Linnean Society     Hybrid Journal   (Followers: 18)

        1 2 3 4 5 6 7 8 | Last

Journal Cover
Antioxidants
Journal Prestige (SJR): 0.847
Citation Impact (citeScore): 3
Number of Followers: 4  

  This is an Open Access Journal Open Access journal
ISSN (Online) 2076-3921
Published by MDPI Homepage  [216 journals]
  • Antioxidants, Vol. 8, Pages 8: Bifunctional Chloroplastic DJ-1B from
           Arabidopsis thaliana is an Oxidation-Robust Holdase and a Glyoxalase
           Sensitive to H2O2

    • Authors: Aleksandra Lewandowska, Trung Vo, Thuy-Dung Nguyen, Khadija Wahni, Didier Vertommen, Frank Van Breusegem, David Young, Joris Messens
      First page: 8
      Abstract: Members of the DJ-1 protein family are multifunctional enzymes whose loss increases the susceptibility of the cell to oxidative stress. However, little is known about the function of the plant DJ-1 homologs. Therefore, we analyzed the effect of oxidation on the structure and function of chloroplastic AtDJ-1B and studied the phenotype of T-DNA lines lacking the protein. In vitro oxidation of AtDJ-1B with H2O2 lowers its glyoxalase activity, but has no effect on its holdase chaperone function. Remarkably, upon oxidation, the thermostability of AtDJ-1B increases with no significant alteration of the overall secondary structure. Moreover, we found that AtDJ-1B transcript levels are invariable, and loss of AtDJ-1B does not affect plant viability, growth and stress response. All in all, two discrete functions of AtDJ-1B respond differently to H2O2, and AtDJ-1B is not essential for plant development under stress.
      Citation: Antioxidants
      PubDate: 2019-01-01
      DOI: 10.3390/antiox8010008
      Issue No: Vol. 8, No. 1 (2019)
       
  • Antioxidants, Vol. 8, Pages 9: NADPH Oxidase (Rboh) Activity is Up
           Regulated during Sweet Pepper (Capsicum annuum L.) Fruit Ripening

    • Authors: Ángela Chu-Puga, Salvador González-Gordo, Marta Rodríguez-Ruiz, José M. Palma, Francisco J. Corpas
      First page: 9
      Abstract: In plants, NADPH oxidase (NOX) is also known as a respiratory burst oxidase homolog (Rboh). This highly important enzyme, one of the main enzymatic sources of superoxide radicals (O2•−), is involved in the metabolism of reactive oxygen and nitrogen species (ROS and RNS), which is active in the non-climacteric pepper (Capsicum annuum L.) fruit. We used sweet pepper fruits at two ripening stages (green and red) to biochemically analyze the O2•−-generating Rboh activity and the number of isozymes during this physiological process. Malondialdehyde (MDA) content, an oxidative stress marker, was also assayed as an index of lipid peroxidation. In red fruits, MDA was observed to increase 2-fold accompanied by a 5.3-fold increase in total Rboh activity. Using in-gel assays of Rboh activity, we identified a total of seven CaRboh isozymes (I–VII) which were differentially modulated during ripening. CaRboh-III and CaRboh-I were the most prominent isozymes in green and red fruits, respectively. An in vitro assay showed that CaRboh activity is inhibited in the presence of nitric oxide (NO) donors, peroxynitrite (ONOO−) and glutathione (GSH), suggesting that CaRboh can undergo S-nitrosation, Tyr-nitration, and glutathionylation, respectively. In summary, this study provides a basic biochemical characterization of CaRboh activity in pepper fruits and indicates that this O2•−-generating Rboh is involved in nitro-oxidative stress associated with sweet pepper fruit ripening.
      Citation: Antioxidants
      PubDate: 2019-01-01
      DOI: 10.3390/antiox8010009
      Issue No: Vol. 8, No. 1 (2019)
       
  • Antioxidants, Vol. 8, Pages 10: Structural and Biochemical Insights into
           the Reactivity of Thioredoxin h1 from Chlamydomonas reinhardtii

    • Authors: Christophe H. Marchand, Simona Fermani, Jacopo Rossi, Libero Gurrieri, Daniele Tedesco, Julien Henri, Francesca Sparla, Paolo Trost, Stéphane D. Lemaire, Mirko Zaffagnini
      First page: 10
      Abstract: Thioredoxins (TRXs) are major protein disulfide reductases of the cell. Their redox activity relies on a conserved Trp-Cys-(Gly/Pro)-Pro-Cys active site bearing two cysteine (Cys) residues that can be found either as free thiols (reduced TRXs) or linked together by a disulfide bond (oxidized TRXs) during the catalytic cycle. Their reactivity is crucial for TRX activity, and depends on the active site microenvironment. Here, we solved and compared the 3D structure of reduced and oxidized TRX h1 from Chlamydomonas reinhardtii (CrTRXh1). The three-dimensional structure was also determined for mutants of each active site Cys. Structural alignments of CrTRXh1 with other structurally solved plant TRXs showed a common spatial fold, despite the low sequence identity. Structural analyses of CrTRXh1 revealed that the protein adopts an identical conformation independently from its redox state. Treatment with iodoacetamide (IAM), a Cys alkylating agent, resulted in a rapid and pH-dependent inactivation of CrTRXh1. Starting from fully reduced CrTRXh1, we determined the acid dissociation constant (pKa) of each active site Cys by Matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry analyses coupled to differential IAM-based alkylation. Based on the diversity of catalytic Cys deprotonation states, the mechanisms and structural features underlying disulfide redox activity are discussed.
      Citation: Antioxidants
      PubDate: 2019-01-01
      DOI: 10.3390/antiox8010010
      Issue No: Vol. 8, No. 1 (2019)
       
  • Antioxidants, Vol. 8, Pages 11: Peroxiredoxins in Cancer and Response to
           Radiation Therapies

    • Authors: Tom E. Forshaw, Reetta Holmila, Kimberly J. Nelson, Joshua E. Lewis, Melissa L. Kemp, Allen W. Tsang, Leslie B. Poole, W. Todd Lowther, Cristina M. Furdui
      First page: 11
      Abstract: Peroxiredoxins have a long-established cellular function as regulators of redox metabolism by catalyzing the reduction of peroxides (e.g., H2O2, lipid peroxides) with high catalytic efficiency. This activity is also critical to the initiation and relay of both phosphorylation and redox signaling in a broad range of pathophysiological contexts. Under normal physiological conditions, peroxiredoxins protect normal cells from oxidative damage that could promote oncogenesis (e.g., environmental stressors). In cancer, higher expression level of peroxiredoxins has been associated with both tumor growth and resistance to radiation therapies. However, this relationship between the expression of peroxiredoxins and the response to radiation is not evident from an analysis of data in The Cancer Genome Atlas (TCGA) or NCI60 panel of cancer cell lines. The focus of this review is to summarize the current experimental knowledge implicating this class of proteins in cancer, and to provide a perspective on the value of targeting peroxiredoxins in the management of cancer. Potential biases in the analysis of the TCGA data with respect to radiation resistance are also highlighted.
      Citation: Antioxidants
      PubDate: 2019-01-01
      DOI: 10.3390/antiox8010011
      Issue No: Vol. 8, No. 1 (2019)
       
  • Antioxidants, Vol. 8, Pages 12: Healthcare Workers Occupationally Exposed
           to Ionizing Radiation Exhibit Altered Levels of Inflammatory Cytokines and
           Redox Parameters

    • Authors: Iman M. Ahmad, Maher Y. Abdalla, Tiffany A. Moore, Lisa Bartenhagen, Adam J. Case, Matthew C. Zimmerman
      First page: 12
      Abstract: Studies have shown an increased risk for a variety of cancers, specifically brain cancer, in healthcare workers occupationally exposed to ionizing radiation. Although the mechanisms mediating these phenomena are not fully understood, ionizing radiation-mediated elevated levels of reactive oxygen species (ROS), oxidative DNA damage, and immune modulation are likely involved. A group of 20 radiation exposed workers and 40 sex- and age-matched non-exposed control subjects were recruited for the study. We measured superoxide (O2•−) levels in whole blood of healthcare workers and all other measurements of cytokines, oxidative DNA damage, extracellular superoxide dismutase (EcSOD) activity and reduced/oxidized glutathione ratio (GSH/GSSG) in plasma. Levels of O2•− were significantly higher in radiation exposed workers compared to control. Similarly, a significant increase in the levels of interleukin (IL)-6, IL-1α and macrophage inflammatory protein (MIP)-1α in radiation exposed workers compared to control was observed, while there was no significance difference in the other 27 screened cytokines. A significant positive correlation was found between MIP-1α and O2•− levels with no correlation in either IL-6 or IL-1α. Further, a dose-dependent relationship with significant O2•− production and immune alterations in radiation exposed workers was demonstrated. There was no statistical difference between the groups in terms of oxidative DNA damage, GSH/GSSG levels, or EcSOD activity. Although the biologic significance of cytokines alterations in radiation exposed workers is unclear, further studies are needed for determining the underlying mechanism of their elevation.
      Citation: Antioxidants
      PubDate: 2019-01-01
      DOI: 10.3390/antiox8010012
      Issue No: Vol. 8, No. 1 (2019)
       
  • Antioxidants, Vol. 8, Pages 13: Comparative Analysis of Antioxidant and
           Anti-Amyloidogenic Properties of Various Polyphenol Rich Phytoceutical
           Extracts

    • Authors: Kody Kleinrichert, Bindhu Alappat
      First page: 13
      Abstract: Though the pathogenesis of Alzheimer’s Disease (AD) is not completely elucidated, it is generally accepted that the aggregation of toxic amyloid-β (Aβ) protein fibrils plays a major role in the disease’s onset and progression. Various phytoceutical compounds have been shown to attenuate Aβ toxicity and disrupt its aggregation, including various types of polyphenolic compounds. These polyphenolic compounds have also been found to demonstrate potent antioxidant activity, which may contribute to their anti-amyloidogenic properties. This study compares three plants, traditionally used for numerous medicinal purposes in Asian countries, including: Curcuma longa (Turmeric), Camellia sinensis (Green Tea), and Scoparia dulcis (Sweet Broomweed). Antioxidant effects of the crude, polyphenol rich phytoceutical extracts from these plants were analyzed using a 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The ability of these extracts to prevent Aβ fibril formation was then carried out in order to establish a relationship between antioxidant activity and Aβ aggregation. A positive correlation between antioxidant efficacy and prevention of Aβ aggregation was demonstrated, indicating that antioxidant activity may play some role in preventing Aβ aggregation.
      Citation: Antioxidants
      PubDate: 2019-01-01
      DOI: 10.3390/antiox8010013
      Issue No: Vol. 8, No. 1 (2019)
       
  • Antioxidants, Vol. 8, Pages 1: Effect of a Strawberry and Spinach Dietary
           Supplement on Spatial Learning in Early and Late Middle-Aged Female Rats

    • Authors: Paula M. Millin, Gina T. Rickert
      First page: 1
      Abstract: The present experiment sought to determine the effect of an eight-week, high antioxidant, whole-foods dietary supplement on Morris Water Maze performance in early and late middle-aged female rats. To improve ecological validity over past experimental studies, rats in the current study received antioxidants by consuming freeze-dried organic strawberries and spinach rather than by being given food extracts or antioxidant injections. Latency and path length measures both indicated that late middle-aged rats fed the high antioxidant diet performed on a par with the younger animals earlier in training than their standard diet counterparts (p < 0.05). Superior performance was not due to improved fitness in the antioxidant-supplemented rats. Thus, our model showed that a high antioxidant diet of relatively short duration mitigated the mild cognitive decline that was seen in control animals during the developmental period of late middle-age. The current results offer support for the promising role of dietary antioxidants in maintaining cognitive health in normal aging and extend past findings to females, who have been relatively neglected in experimental investigations. Moreover, the current model suggests that the period of transition from early to late middle age is a promising target for dietary intervention in healthy adults.
      Citation: Antioxidants
      PubDate: 2018-12-20
      DOI: 10.3390/antiox8010001
      Issue No: Vol. 8, No. 1 (2018)
       
  • Antioxidants, Vol. 8, Pages 2: Potential Application of Prunus armeniaca
           L. and P. domestica L. Leaf Essential Oils as Antioxidant and of
           Cholinesterases Inhibitors

    • Authors: Marco Bonesi, Maria Concetta Tenuta, Monica R. Loizzo, Vincenzo Sicari, Rosa Tundis
      First page: 2
      Abstract: The aim of this work is to investigate the in vitro acetylcholinesterase (AChE) and butyrycholinesterase (BChE) inhibitory activities of essential oils obtained by hydrodistillation from the leaves of Prunus armeniaca and P. domestica in relation to their composition, analysed by Gas Chromatography–Flame Ionization Detector (GC-FID) and Gas Chromatography-Mass Spectrometry (GC-MS) analyses, at different times. Moreover, considering the role of free radicals in the progression of neurodegenerative disorders, the antioxidant properties of essential oils were investigated by using, 2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and β-carotene bleaching tests. The relative antioxidant capacity index (RACI) was used to achieve more comprehensive comparison between analysed antioxidant effects of essential oils. P. armeniaca oils were more active than P. domestica oils against AChE. Against BChE, the most active was the essential oil from P. domestica leaves collected in August with an IC50 value of 95.80 μg/mL. This oil exerted the highest inhibitory activity of lipid peroxidation with IC50 values of 11.15 and 11.39 μg/mL after 30 and 60 min of incubation, respectively. All samples demonstrated a remarkable ABTS radicals scavenging activity, with IC50 values in the range 0.45–0.57 μg/mL in comparison to the positive control, ascorbic acid.
      Citation: Antioxidants
      PubDate: 2018-12-21
      DOI: 10.3390/antiox8010002
      Issue No: Vol. 8, No. 1 (2018)
       
  • Antioxidants, Vol. 8, Pages 3: Suppression of Light-Induced Oxidative
           Stress in the Retina by Mitochondria-Targeted Antioxidant

    • Authors: Viktoriia E. Baksheeva, Veronika V. Tiulina, Natalia K. Tikhomirova, Olga S. Gancharova, Sergey V. Komarov, Pavel P. Philippov, Andrey A. Zamyatnin, Ivan I. Senin, Evgeni Yu. Zernii
      First page: 3
      Abstract: Light-induced oxidation of lipids and proteins provokes retinal injuries and results in progression of degenerative retinal diseases, such as, for instance, iatrogenic photic maculopathies. Having accumulated over years retinal injuries contribute to development of age-related macular degeneration (AMD). Antioxidant treatment is regarded as a promising approach to protecting the retina from light damage and AMD. Here, we examine oxidative processes induced in rabbit retina by excessive light illumination with or without premedication using mitochondria-targeted antioxidant SkQ1 (10-(6’-plastoquinonyl)decyltriphenyl-phosphonium). The retinal extracts obtained from animals euthanized within 1–7 days post exposure were analyzed for H2O2, malondialdehyde (MDA), total antioxidant activity (AOA), and activities of glutathione peroxidase (GPx) and superoxide dismutase (SOD) using colorimetric and luminescence assays. Oxidation of visual arrestin was monitored by immunoblotting. The light exposure induced lipid peroxidation and H2O2 accumulation in the retinal cells. Unexpectedly, it prominently upregulated AOA in retinal extracts although SOD and GPx activities were compromised. These alterations were accompanied by accumulation of disulfide dimers of arrestin revealing oxidative stress in the photoreceptors. Premedication of the eyes with SkQ1 accelerated normalization of H2O2 levels and redox-status of lipids and proteins, contemporarily enhancing AOA and, likely, sustaining normal activity of GPx. Thus, SkQ1 protects the retina from light-induced oxidative stress and could be employed to suppress oxidative damage of proteins and lipids contributing to AMD.
      Citation: Antioxidants
      PubDate: 2018-12-21
      DOI: 10.3390/antiox8010003
      Issue No: Vol. 8, No. 1 (2018)
       
  • Antioxidants, Vol. 8, Pages 4: Oxidation of Peroxiredoxin 6 in the
           

    • Authors: Suiping Zhou, Chandra Dodia, Sheldon I. Feinstein, Sandra Harper, Henry J. Forman, David W. Speicher, Aron B. Fisher
      First page: 4
      Abstract: The expression of the phospholipase A2 activity (aiPLA2) of peroxiredoxin 6 (Prdx6) in the cell cytoplasm is physiologically relevant for the repair of peroxidized cell membranes, but aiPLA2 assay in vitro indicates that, unlike assay at pH 4, activity at cytosolic pH is essentially absent with non-oxidized substrate. However, the addition of glutathione (GSH) to the assay medium significantly increased aiPLA2 activity at cytosolic pH, while oxidized GSH (GSSG) and several other thiols had no effect. By mass spectroscopy (ESI MS), the addition of GSH to Prdx6 paradoxically led to oxidation of its conserved Cys47 residue to a sulfinic acid. The effect of GSH on PLA2 activity was abolished by incubation under anaerobic conditions, confirming that auto-oxidation of the protein was the mechanism for the GSH effect. Analysis by circular dichroism (CD) and tryptophan fluorescence showed alterations of the protein structure in the presence of GSH. Independently of GSH, the oxidation of Prdx6 by exposure to H2O2 or the presence of oxidized phospholipid as substrate also significantly increased aiPLA2 activity at pH 7. We conclude that the oxidation of the peroxidatically active Cys47 of Prdx6 results in an increase of aiPLA2 activity at pH 7 without effect on the activity of the enzyme at pH 4.
      Citation: Antioxidants
      PubDate: 2018-12-24
      DOI: 10.3390/antiox8010004
      Issue No: Vol. 8, No. 1 (2018)
       
  • Antioxidants, Vol. 8, Pages 5: Antioxidant Capacity and Phytonutrient
           Content in the Seed Coat and Cotyledon of Common Beans (Phaseolus vulgaris
           L.) from Various Regions in Mexico

    • Authors: Celia Chávez-Mendoza, Karla Ivonne Hernández-Figueroa, Esteban Sánchez
      First page: 5
      Abstract: The common bean is a good source of protein and bioactive substances giving it a large antioxidant capacity. The extensive variability of bean genotypes creates the need to characterize them with regard to their nutritional value as a tool in biofortification programs. The purpose of this study was to obtain the antioxidant capacity and phytonutrient content both in the seed coat and the cotyledon of 12 common bean varieties from different regions in Mexico. In the case of the whole seed, lightness (L*), a* (red-purple) and b* (yellow-purple) color coordinates were determined, as well as the chroma and hue angle. In the case of the seed coat and the cotyledon, the protein content, the phytonutrient content and the antioxidant capacity (2,2-diphenyl-1-picrylhydrazyl (DPPH)) were evaluated. A significant difference was observed (p ≤ 0.05) among bean varieties and between seed coat and cotyledon in all variables evaluated. Cotyledon showed a higher content of protein, H, Ni, Zn, Cu, N, P, K S and Mn, while the seed coat showed a higher content of Fe, Ca and Mg and a greater antioxidant capacity (59.99%). The Higuera Azufrado bean variety stood out as having a higher content of N, S and protein. We have concluded that the nutritional characterization performed on Mexican bean varieties represents a valuable tool for genetic enhancement programs and crop biofortification strategies.
      Citation: Antioxidants
      PubDate: 2018-12-25
      DOI: 10.3390/antiox8010005
      Issue No: Vol. 8, No. 1 (2018)
       
  • Antioxidants, Vol. 8, Pages 6: Mammary Stem Cells in Domestic Animals: The
           Role of ROS

    • Authors: Mario Baratta, Silvia Miretti, Elisabetta Macchi, Paolo Accornero, Eugenio Martignani
      First page: 6
      Abstract: Reactive oxygen species (ROS) are produced as a natural byproduct of the normal metabolism of oxygen and play significant roles in cell signaling and homeostasis. Although ROS have been involved in pathological processes as diverse as cancer, cardiovascular disease, and aging, they may to exert an effect even in a physiological context. In the central nervous system, stem cells and hematopoietic stem cells are early progenitors that contain lower levels of ROS than their more mature progeny. These different concentrations have been reported to be crucial for maintaining stem cell function. Mammary gland remodeling has been proposed to be organized through the activation and regulation of cells with stemness, either considered real stem cells or primitive precursors. Given the state of oxidative stress in the mammary gland tissue induced by high milk production, in particular in highly productive dairy cows; several studies have focused on the relationship between adult mammary stem cells and the oxidative state of the gland. The oxidative state of the mammary gland appears to be involved in the initial development and metastasis of breast cancer through interference with mammary cancerous stem cells. This review summarizes some links between the mammary stem and oxidative state of the gland.
      Citation: Antioxidants
      PubDate: 2018-12-26
      DOI: 10.3390/antiox8010006
      Issue No: Vol. 8, No. 1 (2018)
       
  • Antioxidants, Vol. 8, Pages 7: Anti-Oxidant and Tyrosinase Inhibitory In
           Vitro Activity of Amino Acids and Small Peptides: New Hints for the
           Multifaceted Treatment of Neurologic and Metabolic Disfunctions

    • Authors: Grazia Luisi, Azzurra Stefanucci, Gokhan Zengin, Marilisa Pia Dimmito, Adriano Mollica
      First page: 7
      Abstract: Oxidative damage is among the factors associated with the onset of chronic pathologies, such as neurodegenerative and metabolic diseases. Several classes of anti-oxidant compounds have been suggested as having a protective role against cellular stressors, but, in this perspective, peptides’ world represents a poorly explored source. In the present study, the free radical scavenging properties, the metal ion reducing power, and the metal chelating activity of a series of sulfurated amino acids and tripeptides were determined in vitro through canonical assays (DPPH, ABTS, CUPRAC, FRAP, PM, and EECC) and estimated in comparison with the corresponding activities of synthetic peptide semicarbazones, incorporating the peculiar non-proteinogenic amino acid, tert-leucine (tLeu). The compounds exhibited remarkable anti-oxidant properties. As expected, sulfurated compounds 1–5 were found to be the most efficient radical scavengers and strongest reductants. Nevertheless, tLeu-containing peptides 7 and 8 disclosed notable metal reducing and chelating activities. These unprecedented results indicate that tLeu-featuring di- and tripeptide backbones, bearing the semicarbazone chelating moiety, are compatible with the emergence of an anti-oxidant potential. Additionally, when tested against a panel of enzymes usually targeted for therapeutic purposes in neurodegenerative and metabolic disorders, all samples were found to be good inhibitors of tyrosinase.
      Citation: Antioxidants
      PubDate: 2018-12-26
      DOI: 10.3390/antiox8010007
      Issue No: Vol. 8, No. 1 (2018)
       
  • Antioxidants, Vol. 7, Pages 111: Role of Presenilin in Mitochondrial
           Oxidative Stress and Neurodegeneration in Caenorhabditis elegans

    • Authors: Shaarika Sarasija, Kenneth R. Norman
      First page: 111
      Abstract: Neurodegenerative diseases like Alzheimer’s disease (AD) are poised to become a global health crisis, and therefore understanding the mechanisms underlying the pathogenesis is critical for the development of therapeutic strategies. Mutations in genes encoding presenilin (PSEN) occur in most familial Alzheimer’s disease but the role of PSEN in AD is not fully understood. In this review, the potential modes of pathogenesis of AD are discussed, focusing on calcium homeostasis and mitochondrial function. Moreover, research using Caenorhabditis elegans to explore the effects of calcium dysregulation due to presenilin mutations on mitochondrial function, oxidative stress and neurodegeneration is explored.
      Citation: Antioxidants
      PubDate: 2018-08-24
      DOI: 10.3390/antiox7090111
      Issue No: Vol. 7, No. 9 (2018)
       
  • Antioxidants, Vol. 7, Pages 112: Astrocyte Antioxidant Systems

    • Authors: Gethin J. McBean
      First page: 112
      Abstract: n/a
      Citation: Antioxidants
      PubDate: 2018-08-27
      DOI: 10.3390/antiox7090112
      Issue No: Vol. 7, No. 9 (2018)
       
  • Antioxidants, Vol. 7, Pages 113: Investigation into the Thermal Response
           and Pharmacological Activity of Substituted Schiff Bases on α-Amylase and
           α-Glucosidase

    • Authors: Bamidele Joseph Okoli, Johannes Sekomeng Modise
      First page: 113
      Abstract: The emphasis of previous studies has targeted the development of insulin mimic with little attention given to the development of metabolic enzyme inhibitors. Our focus is to synthesise nine o-hydroxy and p-nitro-azomethine analogues, investigate their digestive enzyme inhibitory capacity, as well as the antioxidant and antimicrobial activities. The substituted Schiff bases were analysed using thermal gravimetric analyser (TGA), X-ray diffractometer (XRD), nuclear magnetic resonance spectroscopy (NMR), elemental analyser, and Fourier-transform infrared spectroscopy (FT-IR). Determination of synthetic yield revealed that the o-hydroxy analogues produced the highest yield of ≥77.1% compared to p-nitro and unsubstituted analogues. Spectra study showed the presence of azomethine stretching vibration at 1698–1613 cm−1, proton signals at δ 8.46–9.81, and carbon signals at δ 145.95–159.53 ppm. Investigation into the thermal property indicated an elevated melting point for the o-hydroxy analogue, compared to the p-nitro derivative which showed high stability to heat. There are similarities in crystalline structure with few unique patterns suggesting different substituent group. The antioxidant activities of the substituted analogues registered low half maximal inhibitory concentration (IC50), with exception to the ferric reducing power; indicating that the Schiff bases are weak siderophores. All nine Schiff bases were bacteriostatic or fungistatic at the screened concentrations; however, the nitro-substituted analogues have an enhanced activity with Minimum Inhibitory Concentration (MIC) values of 0.03–2.54 µM. Both o-hydroxy and p-nitro-substitution does not improve the antifungal activity of the compounds against A. niger. The o-hydroxyl and p-nitro Schiff base derivatives showed enhanced activity towards the inhibition of α -amylase and α-glucosidase by hydroxylation and glycosylation, respectively. Although, hydroxy derivatives of sulphonic acid derived Schiff base slightly decreased the activities on α-glucosidase and α-amylase. Our findings suggest that p-nitro substitution enhances the in vitro nonenzymatic activity while the o-hydroxy derivatives are good hydrolase inhibitors. Therefore, substituent modification can be used as an enhancement technique in designing novel pharmacophore.
      Citation: Antioxidants
      PubDate: 2018-08-28
      DOI: 10.3390/antiox7090113
      Issue No: Vol. 7, No. 9 (2018)
       
  • Antioxidants, Vol. 7, Pages 114: Physiological Roles of Plant Methionine
           Sulfoxide Reductases in Redox Homeostasis and Signaling

    • Authors: Pascal Rey, Lionel Tarrago
      First page: 114
      Abstract: Oxidation of methionine (Met) leads to the formation of two S- and R-diastereoisomers of Met sulfoxide (MetO) that are reduced back to Met by methionine sulfoxide reductases (MSRs), A and B, respectively. Here, we review the current knowledge about the physiological functions of plant MSRs in relation with subcellular and tissue distribution, expression patterns, mutant phenotypes, and possible targets. The data gained from modified lines of plant models and crop species indicate that MSRs play protective roles upon abiotic and biotic environmental constraints. They also participate in the control of the ageing process, as shown in seeds subjected to adverse conditions. Significant advances were achieved towards understanding how MSRs could fulfil these functions via the identification of partners among Met-rich or MetO-containing proteins, notably by using redox proteomic approaches. In addition to a global protective role against oxidative damage in proteins, plant MSRs could specifically preserve the activity of stress responsive effectors such as glutathione-S-transferases and chaperones. Moreover, several lines of evidence indicate that MSRs fulfil key signaling roles via interplays with Ca2+- and phosphorylation-dependent cascades, thus transmitting ROS-related information in transduction pathways.
      Citation: Antioxidants
      PubDate: 2018-08-29
      DOI: 10.3390/antiox7090114
      Issue No: Vol. 7, No. 9 (2018)
       
  • Antioxidants, Vol. 7, Pages 115: The Use of Intravenous Vitamin C as a
           Supportive Therapy for a Patient with Glioblastoma Multiforme

    • Authors: Nicola Baillie, Anitra C. Carr, Selene Peng
      First page: 115
      Abstract: Glioblastoma multiforme is a high grade malignant brain tumour with a poor prognosis. Here we report the case of a woman with glioblastoma who lived for over four years from diagnosis (median survival 12 months and 2% survival for three years), experiencing good quality of life for most of that time. She underwent initial debulking craniotomy, radiotherapy and chemotherapy, as well as having intravenous vitamin C infusions 2–3 times weekly over the four years from diagnosis. Her progress was monitored by blood tests, regular computerised tomography (CT) and magnetic resonance imaging (MRI) scans, clinical reviews and European Organization for the Research and Treatment of Cancer quality of life questionnaires (EORTC QLQ C30). Our case report highlights the benefits of intravenous vitamin C as a supportive therapy for patients with glioblastoma.
      Citation: Antioxidants
      PubDate: 2018-08-30
      DOI: 10.3390/antiox7090115
      Issue No: Vol. 7, No. 9 (2018)
       
  • Antioxidants, Vol. 7, Pages 116: Unbiased Identification of Proteins
           Covalently Modified by Complex Mixtures of Peroxidized Lipids Using a
           

    • Authors: Bernd Gesslbauer, David Kuerzl, Niko Valpatic, Valery N. Bochkov
      First page: 116
      Abstract: Covalent modification of functionally important cell proteins by lipid oxidation products (LOPs) is a known mechanism initiating pathological consequences of oxidative stress. Identification of new proteins covalently modified by electrophilic lipids can be performed by a combination of chemical, immunological, and mass spectrometry-based methods, but requires prior knowledge either on the exact molecular structure of LOPs (e.g., 4-hydroxynonenal) or candidate protein targets. However, under the conditions of oxidative stress in vivo, a complex mixture of proteins (e.g., cytosolic proteome) reacts with a complex mixture of LOPs. Here we describe a method for detection of lipid-modified proteins that does not require an a priori knowledge on the chemical structure of LOPs or identity of target proteins. The method is based on the change of electrophoretic mobility of lipid-modified proteins, which is induced by conformational changes and cross-linking with other proteins. Abnormally migrating proteins are detected by mass spectrometry-based protein peptide sequencing. We applied this method to study effects of oxidized palmitoyl-arachidonoyl-phosphatidylcholine (OxPAPC) on endothelial cells. Several known, but also many new, OxPAPC-binding proteins were identified. We expect that this technically relatively simple method can be widely applied for label-free analysis of lipid-protein interactions in complex protein samples treated with different LOPs.
      Citation: Antioxidants
      PubDate: 2018-08-30
      DOI: 10.3390/antiox7090116
      Issue No: Vol. 7, No. 9 (2018)
       
  • Antioxidants, Vol. 7, Pages 117: Effect of Different Cooking Methods on
           Polyphenols, Carotenoids and Antioxidant Activities of Selected Edible
           Leaves

    • Authors: K. D. Prasanna P. Gunathilake, K. K. D. Somathilaka Ranaweera, H. P. Vasantha Rupasinghe
      First page: 117
      Abstract: This study aimed to evaluate the effect of cooking (boiling, steaming, and frying) on polyphenols, flavonoids, carotenoids and antioxidant activity of six edible leaves. The total antioxidant capacity of the fresh and cooked leaves was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and singlet oxygen scavenging assays. The results revealed that frying caused a reduction in major bioactives and antioxidant activities in all leafy vegetables tested. However, steamed and boiled leaves of C. auriculata and C. asiatica have shown greater levels of polyphenols, flavonoids, and antioxidant capacity compared with fresh leaves. Polyphenol and flavonoid contents of boiled S. grandiflora and G. lactiferum were higher than that of their fresh form. Boiled and steamed O. zeylanica and S. grandiflora have shown higher carotenoids. Boiled and steamed leaves of P. edulis have shown higher antioxidant activity. The impact of cooking on the changes in bioactive concentrations and antioxidant capacities are dependent on the species and the method of cooking.
      Citation: Antioxidants
      PubDate: 2018-08-30
      DOI: 10.3390/antiox7090117
      Issue No: Vol. 7, No. 9 (2018)
       
  • Antioxidants, Vol. 7, Pages 118: 4-Hydroxynonenal in Redox Homeostasis of
           Gastrointestinal Mucosa: Implications for the Stomach in Health and
           Diseases

    • Authors: Andriy Cherkas, Neven Zarkovic
      First page: 118
      Abstract: Maintenance of integrity and function of the gastric mucosa (GM) requires a high regeneration rate of epithelial cells during the whole life span. The health of the gastric epithelium highly depends on redox homeostasis, antioxidant defense, and activity of detoxifying systems within the cells, as well as robustness of blood supply. Bioactive products of lipid peroxidation, in particular, second messengers of free radicals, the bellwether of which is 4-hydroxynonenal (HNE), are important mediators in physiological adaptive reactions and signaling, but they are also thought to be implicated in the pathogenesis of numerous gastric diseases. Molecular mechanisms and consequences of increased production of HNE, and its protein adducts, in response to stressors during acute and chronic gastric injury, are well studied. However, several important issues related to the role of HNE in gastric carcinogenesis, tumor growth and progression, the condition of GM after eradication of Helicobacter pylori, or the relevance of antioxidants for HNE-related redox homeostasis in GM, still need more studies and new comprehensive approaches. In this regard, preclinical studies and clinical intervention trials are required, which should also include the use of state-of-the-art analytical techniques, such as HNE determination by immunohistochemistry and enzyme-linked immunosorbent assay (ELISA), as well as modern mass-spectroscopy methods.
      Citation: Antioxidants
      PubDate: 2018-09-03
      DOI: 10.3390/antiox7090118
      Issue No: Vol. 7, No. 9 (2018)
       
  • Antioxidants, Vol. 7, Pages 119: Exercise-Induced Oxidative Stress and the
           Effects of Antioxidant Intake from a Physiological Viewpoint

    • Authors: Takuji Kawamura, Isao Muraoka
      First page: 119
      Abstract: It is well established that the increase in reactive oxygen species (ROS) and free radicals production during exercise has both positive and negative physiological effects. Among them, the present review focuses on oxidative stress caused by acute exercise, mainly on evidence in healthy individuals. This review also summarizes findings on the determinants of exercise-induced oxidative stress and sources of free radical production. Moreover, we outline the effects of antioxidant supplementation on exercise-induced oxidative stress, which have been studied extensively. Finally, the following review briefly summarizes future tasks in the field of redox biology of exercise. In principle, this review covers findings for the whole body, and describes human trials and animal experiments separately.
      Citation: Antioxidants
      PubDate: 2018-09-05
      DOI: 10.3390/antiox7090119
      Issue No: Vol. 7, No. 9 (2018)
       
  • Antioxidants, Vol. 7, Pages 120: Bark of Passiflora edulis Treatment
           Stimulates Antioxidant Capacity, and Reduces Dyslipidemia and Body Fat in
           db/db Mice

    • Authors: Marielle Fernanda Panelli, Damiana Tortolero Pierine, Sérgio Luiz Borges de Souza, Artur Júnio Togneri Ferron, Jéssica Leite Garcia, Klinsmann Carolo dos Santos, Matheus Antônio Filiol Belin, Giuseppina Pace Pereira Lima, Milena Galhardo Borguini, Igor Otávio Minatel, Antônio Carlos Cicogna, Fabiane Valentini Francisqueti, Camila Renata Corrêa
      First page: 120
      Abstract: Obesity is considered an important risk factor for several disorders, such as diabetes mellitus, systemic arterial hypertension, dyslipidemia, and atherosclerosis, which are associated with inflammation and oxidative stress as a trigger factor. Passiflora edulis contains important bioactive compounds, such as phenolics, carotenoids, vitamin C, and polyamines in pulp, leaves, seeds, and bark. Aim: To evaluate the effect of bark of Passiflora edulis (BPe) on body composition, and metabolic and oxidative stress parameters in genetically obese mice. Methods: Obese male db/db mice (n = 14 animals) received normal feeds and water ad libitum for 8 weeks. Then, animals were randomly divided to continue either receiving standard chow (obese, n = 7 (OB)) or feed with standard chow plus bark Passiflora edulis (BPe) (obese + BPe, n = 7 (OB + BPe)) for 8 more weeks, totaling 16 weeks. BPe was added to chow (7 g of BPe/kg of chow corresponding to 1.5 g/kg of body weight). The parameters evaluated in animals included food and caloric intake, body weight, body fat, plasma glucose, triglycerides, and total cholesterol. Malondialdehyde and antioxidant capacity were evaluated in plasma and organs. Groups were compared by Student t-test, with p < 0.05. Results: BPe reduced visceral and subcutaneous fat deposit and adiposity index, cholesterol and triglyceride levels, ameliorated the antioxidant capacity, and reduced malondialdehyde (MDA) levels. Conclusion: the bark of Passiflora edulis was effective in improving body composition, and metabolic and antioxidant parameters in obese mice.
      Citation: Antioxidants
      PubDate: 2018-09-08
      DOI: 10.3390/antiox7090120
      Issue No: Vol. 7, No. 9 (2018)
       
  • Antioxidants, Vol. 7, Pages 121: PCB11 Metabolite,
           3,3’-Dichlorobiphenyl-4-ol, Exposure Alters the Expression of Genes
           Governing Fatty Acid Metabolism in the Absence of Functional Sirtuin 3:
           Examining the Contribution of MnSOD

    • Authors: Sinthia Alam, Gwendolyn S. Carter, Kimberly J. Krager, Xueshu Li, Hans-Joachim Lehmler, Nukhet Aykin-Burns
      First page: 121
      Abstract: Although the production of polychlorinated biphenyls (PCBs) is prohibited, the inadvertent production of certain lower-chlorinated PCB congeners still threatens human health. We and others have identified 3,3’-dichlorobiphenyl (PCB11) and its metabolite, 3,3’-dichlorobiphenyl-4-ol (4OH-PCB11), in human blood, and there is a correlation between exposure to this metabolite and mitochondrial oxidative stress in mammalian cells. Here, we evaluated the downstream effects of 4OH-PCB11 on mitochondrial metabolism and function in the presence and absence of functional Sirtuin 3 (SIRT3), a mitochondrial fidelity protein that protects redox homeostasis. A 24 h exposure to 3 μM 4OH-PCB11 significantly decreased the cellular growth and mitochondrial membrane potential of SIRT3-knockout mouse embryonic fibroblasts (MEFs). Only wild-type cells demonstrated an increase in Manganese superoxide dismutase (MnSOD) activity in response to 4OH-PCB11–induced oxidative injury. This suggests the presence of a SIRT3-mediated post-translational modification to MnSOD, which was impaired in SIRT3-knockout MEFs, which counters the PCB insult. We found that 4OH-PCB11 increased mitochondrial respiration and endogenous fatty-acid oxidation-associated oxygen consumption in SIRT3-knockout MEFs; this appeared to occur because the cells exhausted their reserve respiratory capacity. To determine whether these changes in mitochondrial respiration were accompanied by similar changes in the regulation of fatty acid metabolism, we performed quantitative real-time polymerase chain reaction (qRT-PCR) after a 24 h treatment with 4OH-PCB11. In SIRT3-knockout MEFs, 4OH-PCB11 significantly increased the expression of ten genes controlling fatty acid biosynthesis, metabolism, and transport. When we overexpressed MnSOD in these cells, the expression of six of these genes returned to the baseline level, suggesting that the protective role of SIRT3 against 4OH-PCB11 is partially governed by MnSOD activity.
      Citation: Antioxidants
      PubDate: 2018-09-15
      DOI: 10.3390/antiox7090121
      Issue No: Vol. 7, No. 9 (2018)
       
  • Antioxidants, Vol. 7, Pages 122: The Functions of the Mammalian Methionine
           Sulfoxide Reductase System and Related Diseases

    • Authors: Beichen Jiang, Jackob Moskovitz
      First page: 122
      Abstract: This review article describes and discusses the current knowledge on the general role of the methionine sulfoxide reductase (MSR) system and the particular role of MSR type A (MSRA) in mammals. A powerful tool to investigate the contribution of MSRA to molecular processes within a mammalian system/organism is the MSRA knockout. The deficiency of MSRA in this mouse model provides hints and evidence for this enzyme function in health and disease. Accordingly, the potential involvement of MSRA in the processes leading to neurodegenerative diseases, neurological disorders, cystic fibrosis, cancer, and hearing loss will be deliberated and evaluated.
      Citation: Antioxidants
      PubDate: 2018-09-18
      DOI: 10.3390/antiox7090122
      Issue No: Vol. 7, No. 9 (2018)
       
  • Antioxidants, Vol. 7, Pages 123: Antioxidative 1,4-Dihydropyridine
           Derivatives Modulate Oxidative Stress and Growth of Human Osteoblast-Like
           Cells In Vitro

    • Authors: Lidija Milkovic, Tea Vukovic, Neven Zarkovic, Franz Tatzber, Egils Bisenieks, Zenta Kalme, Imanta Bruvere, Zaiga Ogle, Janis Poikans, Astrida Velena, Gunars Duburs
      First page: 123
      Abstract: Oxidative stress has been implicated in pathophysiology of different human stress- and age-associated disorders, including osteoporosis for which antioxidants could be considered as therapeutic remedies as was suggested recently. The 1,4-dihydropyridine (DHP) derivatives are known for their pleiotropic activity, with some also acting as antioxidants. To find compounds with potential antioxidative activity, a group of 27 structurally diverse DHPs, as well as one pyridine compound, were studied. A group of 11 DHPs with 10-fold higher antioxidative potential than of uric acid, were further tested in cell model of human osteoblast-like cells. Short-term combined effects of DHPs and 50 µM H2O2 (1-h each), revealed better antioxidative potential of DHPs if administered before a stressor. Indirect 24-h effect of DHPs was evaluated in cells further exposed to mild oxidative stress conditions induced either by H2O2 or tert-butyl hydroperoxide (both 50 µM). Cell growth (viability and proliferation), generation of ROS and intracellular glutathione concentration were evaluated. The promotion of cell growth was highly dependent on the concentrations of DHPs used, type of stressor applied and treatment set-up. Thiocarbatone III-1, E2-134-1 III-4, Carbatone II-1, AV-153 IV-1, and Diethone I could be considered as therapeutic agents for osteoporosis although further research is needed to elucidate their bioactivity mechanisms, in particular in respect to signaling pathways involving 4-hydroxynoneal and related second messengers of free radicals.
      Citation: Antioxidants
      PubDate: 2018-09-19
      DOI: 10.3390/antiox7090123
      Issue No: Vol. 7, No. 9 (2018)
       
  • Antioxidants, Vol. 7, Pages 170: Biological Relevance of Extra Virgin
           Olive Oil Polyphenols Metabolites

    • Authors: Gabriele Serreli, Monica Deiana
      First page: 170
      Abstract: Extra virgin olive oil (EVOO) polyphenols beneficial effects have widely been debated throughout the last three decades, with greater attention to hydroxytyrosol and tyrosol, which are by far the most studied. The main concern about the evaluation of EVOO phenols activities in vitro and in vivo is that the absorption and metabolism of these compounds once ingested lead to the production of different metabolites in the human body. EVOO phenols in the ingested forms are less concentrated in human tissues than their glucuronide, sulfate and methyl metabolites; on the other hand, metabolites may undergo deconjugation before entering the cells and thus act as free forms or may be reformed inside the cells so acting as conjugated forms. In most in vitro studies the presence of methyl/sulfate/glucuronide functional groups does not seem to inhibit biological activity. Parent compounds and metabolites have been shown to reach tissue concentrations useful to exert beneficial effects others than antioxidant and scavenging properties, by modulating intracellular signaling and improving cellular response to oxidative stress and pro-inflammatory stimuli. This review aims to give an overview on the reported evidence of the positive effects exerted by the main EVOO polyphenols metabolites in comparison with the parent compounds.
      Citation: Antioxidants
      PubDate: 2018-11-22
      DOI: 10.3390/antiox7120170
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 171: Crystal Structure of Chloroplastic
           Thioredoxin f2 from Chlamydomonas reinhardtii Reveals Distinct Surface
           Properties

    • Authors: Stéphane D. Lemaire, Daniele Tedesco, Pierre Crozet, Laure Michelet, Simona Fermani, Mirko Zaffagnini, Julien Henri
      First page: 171
      Abstract: Protein disulfide reduction by thioredoxins (TRXs) controls the conformation of enzyme active sites and their multimeric complex formation. TRXs are small oxidoreductases that are broadly conserved in all living organisms. In photosynthetic eukaryotes, TRXs form a large multigenic family, and they have been classified in different types: f, m, x, y, and z types are chloroplastic, while o and h types are located in mitochondria and cytosol. In the model unicellular alga Chlamydomonas reinhardtii, the TRX family contains seven types, with f- and h-types represented by two isozymes. Type-f TRXs interact specifically with targets in the chloroplast, controlling photosynthetic carbon fixation by the Calvin–Benson cycle. We solved the crystal structures of TRX f2 and TRX h1 from C. reinhardtii. The systematic comparison of their atomic features revealed a specific conserved electropositive crown around the active site of TRX f, complementary to the electronegative surface of their targets. We postulate that this surface provides specificity to each type of TRX.
      Citation: Antioxidants
      PubDate: 2018-11-23
      DOI: 10.3390/antiox7120171
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 172: The Role of Peroxiredoxin 6 in Cell
           Signaling

    • Authors: José A. Arevalo, José Pablo Vázquez-Medina
      First page: 172
      Abstract: Peroxiredoxin 6 (Prdx6, 1-cys peroxiredoxin) is a unique member of the peroxiredoxin family that, in contrast to other mammalian peroxiredoxins, lacks a resolving cysteine and uses glutathione and π glutathione S-transferase to complete its catalytic cycle. Prdx6 is also the only peroxiredoxin capable of reducing phospholipid hydroperoxides through its glutathione peroxidase (Gpx) activity. In addition to its peroxidase activity, Prdx6 expresses acidic calcium-independent phospholipase A2 (aiPLA2) and lysophosphatidylcholine acyl transferase (LPCAT) activities in separate catalytic sites. Prdx6 plays crucial roles in lung phospholipid metabolism, lipid peroxidation repair, and inflammatory signaling. Here, we review how the distinct activities of Prdx6 are regulated during physiological and pathological conditions, in addition to the role of Prdx6 in cellular signaling and disease.
      Citation: Antioxidants
      PubDate: 2018-11-24
      DOI: 10.3390/antiox7120172
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 173: Peroxiredoxin 6: The Protector of Male
           Fertility

    • Authors: Cristian O’Flaherty
      First page: 173
      Abstract: The spermatozoon is a terminal cell with the unique purpose of delivering the paternal genome to the oocyte during fertilization. Once spermatozoa enter into the female reproductive tract, they count on only the antioxidant protection that they received during spermatogenesis and epididymal maturation. Peroxiredoxins (PRDXs), particularly PRDX6, are important players in the antioxidant protection and regulation of reactive oxygen species (ROS) levels in spermatozoa. PRDX6, through its peroxidase and calcium-independent phospholipase A2 activities, plays a major role in the regulation of ROS to maintain viability and motility and allow the spermatozoon to achieve fertilizing ability during the complex process of capacitation. The absence of PRDX6 is sufficient to promote abnormal reproductive outcomes in mice that resemble what we observe in infertile men. Indeed, Prdx6−/− spermatozoa display low motility and severe DNA damage, which is translated into reduced ability to fertilize oocytes in vitro or produce a low number of pups compared to wild-type controls. This review focuses on the role of PRDX6 as the primary antioxidant enzyme that protects the spermatozoon from oxidative-stress-associated damages to protect the paternal genome and assure fertility.
      Citation: Antioxidants
      PubDate: 2018-11-24
      DOI: 10.3390/antiox7120173
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 174: Study of the Selectivity and Bioactivity
           of Polyphenols Using Infrared Assisted Extraction from Apricot Pomace
           Compared to Conventional Methods

    • Authors: Dina Cheaib, Nada El Darra, Hiba N. Rajha, Iman El-Ghazzawi, Youssef Mouneimne, Adla Jammoul, Richard G. Maroun, Nicolas Louka
      First page: 174
      Abstract: The valorization of industrial food byproducts by means of environment-friendly extraction methods is becoming a major interest because of its environmental and economic values. In this study, the efficiency of many technologies, such as ultrasounds (US), microwaves (MW), and infrared (IR), was compared, in terms of polyphenol yield and bioactivity from apricot pomace. IR was the most effective method with the highest polyphenol (10 mg GAE/g DM), flavonoid (6 mg CE/g DM), and tannin (3.6 mg/L) yields. In terms of efficacy, IR was followed by MW, US, then solid-liquid (S/L) extraction. IR extract from apricot pomace exhibited the highest inhibitory activity against all the studied gram-positive strains (Methicillin Resistant Staphylococcus aureus, Staphylococcus aureus, Methicillin-resistant Staphylococcus epidermidis, and Staphylococcus epidermidis) and a one gram-negative strain (Escherichia coli). Moreover, IR extracts had by far the highest antiradical activity (AC) (40%) followed by MW (31%), US (28%), and then S/L (15%). High-performance liquid chromatography (HPLC) permitted the identification and quantification of rutin in all extracts; whereas catechin was detected in those of IR (3.1 μg/g DM), MW (2.1 μg/g DM), and US (1.5 μg/g DM). Epicatechin was exclusively found in IR extract (4 μg/g DM), suggesting the selectivity of IR towards this compound. Scanning electron microscopy (SEM) revealed that the IR technique induced the highest cellular and structural damage in apricot pomace, which could explain the effectiveness of this technology.
      Citation: Antioxidants
      PubDate: 2018-11-27
      DOI: 10.3390/antiox7120174
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 175: Enrichment and Assessment of the
           Contributions of the Major Polyphenols to the Total Antioxidant Activity
           of Onion Extracts: A Fractionation by Flash Chromatography Approach

    • Authors: Mohammad B. Hossain, Justine Lebelle, Rares Birsan, Dilip K. Rai
      First page: 175
      Abstract: The present study extensively fractionated crude red onion extract in order to identify the polyphenols which contributed most in the total antioxidant capacity of the onion extract using a flash chromatography system. The flash separations produced 70 fractions which were tested for their total phenol content, total flavonoid content, and antioxidant capacities as measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays. Out of these 70 fractions, four fractions which were representatives of the four major peaks of the flash chromatograms, were further analysed for their constituent polyphenols using liquid chromatography tandem mass spectrometry (LC-MS/MS). The main contributor of onion antioxidant capacity is quercetin glycoside followed by quercetin aglycone although quercetin aglycone had higher antioxidant capacity than its glycosidic counterparts. High abundance of quercetin glycosides such as quercetin-3,4′-diglucoside and quercetin-4′-glucoside had compensated for their relatively low antioxidant capacities. A Higher degree of glycosylation resulted in lower antioxidant capacity. The fractionation approach also contributed in enrichment of the onion antioxidant polyphenols. A >9 folds enrichment was possible by discarding the early fractions (fractions 1–15) which contained the main bulk of the extracts, predominantly sugars.
      Citation: Antioxidants
      PubDate: 2018-11-27
      DOI: 10.3390/antiox7120175
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 176: Analysis of Protein Oxidative
           Modifications in Follicular Fluid from Fertile Women: Natural Versus
           Stimulated Cycles

    • Authors: Irantzu Pérez-Ruiz, Susana Meijide, María-Luisa Hérnandez, Rosaura Navarro, Zaloa Larreategui, Marcos Ferrando, María-Begoña Ruiz-Larrea, José-Ignacio Ruiz-Sanz
      First page: 176
      Abstract: Oxidative stress is associated with obstetric complications during ovarian hyperstimulation in women undergoing in vitro fertilization. The follicular fluid contains high levels of proteins, which are the main targets of free radicals. The aim of this work was to determine specific biomarkers of non-enzymatic oxidative modifications of proteins from follicular fluid in vivo, and the effect of ovarian stimulation with gonadotropins on these biomarkers. For this purpose, 27 fertile women underwent both a natural and a stimulated cycle. The biomarkers, glutamic semialdehyde (GSA), aminoadipic semialdehyde (AASA), Nε-(carboxymethyl)lysine (CML), and Nε-(carboxyethyl)lysine (CEL), were measured by gas-liquid chromatography coupled to mass spectrometry. Results showed that follicular fluid contained products of protein modifications by direct metal-catalyzed oxidation (GSA and AASA), glycoxidation (CML and CEL), and lipoxidation (CML). GSA was the most abundant biomarker (91.5%). The levels of CML amounted to 6% of the total lesions and were higher than AASA (1.3%) and CEL (1.2%). In the natural cycle, CEL was significantly lower (p < 0.05) than in the stimulated cycle, suggesting that natural cycles are more protected against protein glycoxidation. These findings are the basis for further research to elucidate the possible relevance of this follicular biomarker of advanced glycation end product in fertility programs.
      Citation: Antioxidants
      PubDate: 2018-11-27
      DOI: 10.3390/antiox7120176
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 177: Piecing Together How Peroxiredoxins
           Maintain Genomic Stability

    • Authors: James D. West, Trevor J. Roston, Joseph B. David, Kristin M. Allan, Matthew A. Loberg
      First page: 177
      Abstract: Peroxiredoxins, a highly conserved family of thiol oxidoreductases, play a key role in oxidant detoxification by partnering with the thioredoxin system to protect against oxidative stress. In addition to their peroxidase activity, certain types of peroxiredoxins possess other biochemical activities, including assistance in preventing protein aggregation upon exposure to high levels of oxidants (molecular chaperone activity), and the transduction of redox signals to downstream proteins (redox switch activity). Mice lacking the peroxiredoxin Prdx1 exhibit an increased incidence of tumor formation, whereas baker’s yeast (Saccharomyces cerevisiae) lacking the orthologous peroxiredoxin Tsa1 exhibit a mutator phenotype. Collectively, these findings suggest a potential link between peroxiredoxins, control of genomic stability, and cancer etiology. Here, we examine the potential mechanisms through which Tsa1 lowers mutation rates, taking into account its diverse biochemical roles in oxidant defense, protein homeostasis, and redox signaling as well as its interplay with thioredoxin and thioredoxin substrates, including ribonucleotide reductase. More work is needed to clarify the nuanced mechanism(s) through which this highly conserved peroxidase influences genome stability, and to determine if this mechanism is similar across a range of species.
      Citation: Antioxidants
      PubDate: 2018-11-28
      DOI: 10.3390/antiox7120177
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 178: Effect of Extract and Ellagic Acid from
           Geranium schiedeanum on the Antioxidant Defense System in An
           Induced-Necrosis Model

    • Authors: Nancy Vargas-Mendoza, Miguel Vázquez-Velasco, Laura González-Torres, Juana Benedí, Francisco José Sánchez-Muniz, Jose Antonio Morales-González, Osmar Antonio Jaramillo-Morales, Carmen Valadez-Vega, Mirandeli Bautista
      First page: 178
      Abstract: Geranium schiedeanum has been used in traditional therapies as an antiseptic, antipyretic, and as analgesic. The present study was designed to evaluate the pretreatment with G. schiedeanum total extract (GS) and its active metabolites on stimulating the endogenous antioxidant defense system (EADS): catalase (Cat), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR), and glutathione reduction index (RI GSH/GSSG) in rat liver treated with a sublethal dose (6.6 mmol/Kg) of thioacetamide (TAA) in order to probe the capacity of GS and the active compounds to reduce liver injury. This was assessed by measuring aspartate aminotransferase (AST), alanine aminotransferase (ALT), and total bilirubin (BILT) in rats pretreated or not with TAA, and pretreated or not with GS and its metabolites. The results showed that GS was able to induce the production of EADS enzymes, increasing redox index GSH/GSSG at 24 and 48 h after intoxication, and both the extract and the ellagic acid exhibited a significant reduction of hepatic damage markers. Our data confirmed the hepatoprotective effect of GS and its metabolites, like ellagic acid, support the possible use of this extract in the treatment of liver injury.
      Citation: Antioxidants
      PubDate: 2018-11-30
      DOI: 10.3390/antiox7120178
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 179: The Role of Cystinosin in the
           Intermediary Thiol Metabolism and Redox Homeostasis in Kidney Proximal
           Tubular Cells

    • Authors: Rodolfo Sumayao, Philip Newsholme, Tara McMorrow
      First page: 179
      Abstract: Cystinosin is a lysosomal transmembrane protein which facilitates transport of the disulphide amino acid cystine (CySS) from the lysosomes of the cell. This protein is encoded by the CTNS gene which is defective in the lysosomal storage disorder, cystinosis. Because of the apparent involvement of cystinosin in the intermediary thiol metabolism, its discovery has fuelled investigations into its role in modulating cellular redox homeostasis. The kidney proximal tubular cells (PTCs) have become the focus of various studies on cystinosin since the protein is highly expressed in these cells and kidney proximal tubular transport dysfunction is the foremost clinical manifestation of cystinosis. The lysosomal CySS pool is a major source of cytosolic cysteine (Cys), the limiting amino acid for the synthesis of an important antioxidant glutathione (GSH) via the γ-glutamyl cycle. Therefore, loss of cystinosin function is presumed to lead to cytosolic deficit of Cys which may impair GSH synthesis. However, studies using in vitro models lacking cystinosin yielded inconsistent results and failed to establish the mechanistic role of cystinosin in modulating GSH synthesis and redox homeostasis. Because of the complexity of the metabolic micro- and macro-environment in vivo, using in vitro models alone may not be able to capture the complete sequence of biochemical and physiological events that occur as a consequence of loss of cystinosin function. The coexistence of pathways for the overall handling and disposition of GSH, the modulation of CTNS gene by intracellular redox status and the existence of a non-canonical isoform of cystinosin may constitute possible rescue mechanisms in vivo to remediate redox perturbations in renal PTCs. Importantly, the mitochondria seem to play a critical role in orchestrating redox imbalances initiated by cystinosin dysfunction. Non-invasive techniques such as in vivo magnetic resonance imaging with the aid of systems biology approaches may provide invaluable mechanistic insights into the role of cystinosin in the essential intermediary thiol metabolism and in the overall regulation cellular redox homeostasis.
      Citation: Antioxidants
      PubDate: 2018-12-03
      DOI: 10.3390/antiox7120179
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 180: Regulation of Oxidative Stress in Corneal
           Endothelial Cells by Prdx6

    • Authors: Matthew Lovatt, Khadijah Adnan, Gary S. L. Peh, Jodhbir S. Mehta
      First page: 180
      Abstract: The inner layer of the cornea, the corneal endothelium, is post-mitotic and unable to regenerate if damaged. The corneal endothelium is one of the most transplanted tissues in the body. Fuchs’ endothelial corneal dystrophy (FECD) is the leading indication for corneal endothelial transplantation. FECD is thought to be an age-dependent disorder, with a major component related to oxidative stress. Prdx6 is an antioxidant with particular affinity for repairing peroxidised cell membranes. To address the role of Prdx6 in corneal endothelial cells, we used a combination of biochemical and functional studies. Our data reveal that Prdx6 is expressed at unusually high levels at the plasma membrane of corneal endothelial cells. RNAi-mediated knockdown of Prdx6 revealed a role for Prdx6 in lipid peroxidation. Furthermore, following induction of oxidative stress with menadione, Prdx6-deficient cells had defective mitochondrial membrane potential and were more sensitive to cell death. These data reveal that Prdx6 is compartmentalised in corneal endothelial cells and has multiple functions to preserve cellular integrity.
      Citation: Antioxidants
      PubDate: 2018-12-04
      DOI: 10.3390/antiox7120180
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 181: Identification of Small Peptides that
           Inhibit NADPH Oxidase (Nox2) Activation

    • Authors: Aron B. Fisher, Chandra Dodia, Sheldon I. Feinstein
      First page: 181
      Abstract: Nicotinamide adenine phosphate (NADPH) oxidase type 2 (Nox2), a major source of reactive oxygen species in lungs, plays an important role in tissue damage associated with acute inflammatory diseases. The phospholipase A2 (PLA2) activity of peroxiredoxin 6 (Prdx6), called aiPLA2, is required for Nox2 activation through its role in the cellular generation of Rac, a key cytosolic component of the activation cascade. Lung surfactant protein A (SP-A) binds to Prdx6, inhibits its aiPLA2 activity, and prevents activation of Nox2. Based on protein docking software, we previously identified a 16 amino acid (aa) peptide derived from rat SP-A as the Prdx6 binding motif. We now identify the minimal effective sequences of rat/mouse and human SP-A as 9-aa sequences that we have called PLA2-inhibitory peptide (PIP).These sequences are PIP-1, rat/mouse; PIP-2, human; and PIP-3, a hybrid of PIPs 1&2. aiPLA2 activity in vitro was inhibited by 50% with ~7–10 µg PIP/µg Prdx6. Inhibition of the aiPLA2 activity and Nox2 activation of lungs in vivo was similar for intratracheal (IT) and intravenous (IV) administration of PIP-2, but required its incorporation into liposomes as a delivery vehicle; tissue ½ time for decrease of the in vivo inhibition of aiPLA2 activity after PIP-2 administration was ~50 h. These properties suggest that PIP-2 could be an effective therapeutic agent to prevent tissue injury associated with lung inflammation.
      Citation: Antioxidants
      PubDate: 2018-12-05
      DOI: 10.3390/antiox7120181
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 182: Involvement of Glutaredoxin and
           Thioredoxin Systems in the Nitrogen-Fixing Symbiosis between Legumes and
           Rhizobia

    • Authors: Geneviève Alloing, Karine Mandon, Eric Boncompagni, Françoise Montrichard, Pierre Frendo
      First page: 182
      Abstract: Leguminous plants can form a symbiotic relationship with Rhizobium bacteria, during which plants provide bacteria with carbohydrates and an environment appropriate to their metabolism, in return for fixed atmospheric nitrogen. The symbiotic interaction leads to the formation of a new organ, the root nodule, where a coordinated differentiation of plant cells and bacteria occurs. The establishment and functioning of nitrogen-fixing symbiosis involves a redox control important for both the plant-bacteria crosstalk and the regulation of nodule metabolism. In this review, we discuss the involvement of thioredoxin and glutaredoxin systems in the two symbiotic partners during symbiosis. The crucial role of glutathione in redox balance and S-metabolism is presented. We also highlight the specific role of some thioredoxin and glutaredoxin systems in bacterial differentiation. Transcriptomics data concerning genes encoding components and targets of thioredoxin and glutaredoxin systems in connection with the developmental step of the nodule are also considered in the model system Medicago truncatula–Sinorhizobium meliloti.
      Citation: Antioxidants
      PubDate: 2018-12-05
      DOI: 10.3390/antiox7120182
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 183: Redox Regulation of Monodehydroascorbate
           Reductase by Thioredoxin y in Plastids Revealed in the Context of Water
           Stress

    • Authors: Hélène Vanacker, Marjorie Guichard, Anne-Sophie Bohrer, Emmanuelle Issakidis-Bourguet
      First page: 183
      Abstract: Thioredoxins (TRXs) are key players within the complex response network of plants to environmental constraints. Here, the physiological implication of the plastidial y-type TRXs in Arabidopsis drought tolerance was examined. We previously showed that TRXs y1 and y2 have antioxidant functions, and here, the corresponding single and double mutant plants were studied in the context of water deprivation. TRX y mutant plants showed reduced stress tolerance in comparison with wild-type (WT) plants that correlated with an increase in their global protein oxidation levels. Furthermore, at the level of the main antioxidant metabolites, while glutathione pool size and redox state were similarly affected by drought stress in WT and trxy1y2 plants, ascorbate (AsA) became more quickly and strongly oxidized in mutant leaves. Monodehydroascorbate (MDA) is the primary product of AsA oxidation and NAD(P)H-MDA reductase (MDHAR) ensures its reduction. We found that the extractable leaf NADPH-dependent MDHAR activity was strongly activated by TRX y2. Moreover, activity of recombinant plastid Arabidopsis MDHAR isoform (MDHAR6) was specifically increased by reduced TRX y, and not by other plastidial TRXs. Overall, these results reveal a new function for y-type TRXs and highlight their role as major antioxidants in plastids and their importance in plant stress tolerance.
      Citation: Antioxidants
      PubDate: 2018-12-06
      DOI: 10.3390/antiox7120183
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 184: Evaluation of Antioxidant,
           Anti-Inflammatory and Cytoprotective Properties of Ethanolic Mint Extracts
           from Algeria on 7-Ketocholesterol-Treated Murine RAW 264.7 Macrophages

    • Authors: Fatiha Brahmi, Thomas Nury, Meryam Debbabi, Samia Hadj-Ahmed, Amira Zarrouk, Michel Prost, Khodir Madani, Lila Boulekbache-Makhlouf, Gérard Lizard
      First page: 184
      Abstract: The present study consisted in evaluating the antioxidant, anti-inflammatory and cytoprotective properties of ethanolic extracts from three mint species (Mentha spicata L. (MS), Mentha pulegium L. (MP) and Mentha rotundifolia (L.) Huds (MR)) with biochemical methods on murine RAW 264.7 macrophages (a transformed macrophage cell line isolated from ascites of BALB/c mice infected by the Abelson leukemia virus). The total phenolic, flavonoid and carotenoid contents were determined with spectrophotometric methods. The antioxidant activities were quantified with the Kit Radicaux Libres (KRLTM), the ferric reducing antioxidant power (FRAP) and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays. The MS extract showed the highest total phenolic content, and the highest antioxidant capacity, while the MR extract showed the lowest total phenolic content and the lowest antioxidant capacity. The cytoprotective and anti-inflammatory activities of the extracts were quantified on murine RAW 264.7 macrophages treated with 7-ketocholesterol (7KC; 20 µg/mL: 50 µM) associated or not for 24 h and 48 h with ethanolic mint extracts used at different concentrations (25, 50, 100, 200 and 400 µg/mL). Under treatment with 7KC, an important inhibition of cell growth was revealed with the crystal violet test. This side effect was strongly attenuated in a dose dependent manner with the different ethanolic mint extracts, mainly at 48 h. The most important cytoprotective effect was observed with the MS extract. In addition, the effects of ethanolic mint extracts on cytokine secretion (Interleukin (IL)-6, IL-10, Monocyte Chemoattractant Protein (MCP)-1, Interferon (IFN)-ϒ, Tumor necrosis factor (TNF)-α) were determined at 24 h on lipopolysaccharide (LPS, 0.2 µg/mL)-, 7KC (20 µg/mL)- and (7KC + LPS)-treated RAW 264.7 cells. Complex effects of mint extracts were observed on cytokine secretion. However, comparatively to LPS-treated cells, all the extracts strongly reduce IL-6 secretion and two of them (MP and MR) also decrease MCP-1 and TNF-α secretion. However, no anti-inflammatory effects were observed on 7KC- and (7KC + LPS)-treated cells. Altogether, these data bring new evidences on the potential benefits (especially antioxidant and cytoprotective properties) of Algerian mint on human health.
      Citation: Antioxidants
      PubDate: 2018-12-06
      DOI: 10.3390/antiox7120184
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 185: Effect of Agraz (Vaccinium meridionale
           Swartz) on High-Density Lipoprotein Function and Inflammation in Women
           with Metabolic Syndrome

    • Authors: Catalina Marín-Echeverri, Christopher N. Blesso, Maria Luz Fernández, Yeisson Galvis-Pérez, Gelmy Ciro-Gómez, Vitelbina Núñez-Rangel, Juan C. Aristizábal, Jacqueline Barona-Acevedo
      First page: 185
      Abstract: Metabolic syndrome (MetS) is associated with low-grade inflammation and high-density lipoprotein (HDL) dysfunction. Polyphenol-rich foods may improve these alterations. Agraz is a fruit rich in polyphenols (mainly anthocyanins); however, there is limited information about its effects on human health. We evaluated the effects of agraz consumption as compared to placebo on HDL function and inflammation in women with MetS. Forty volunteers (25–60 years) were included in this double-blind crossover study. Women consumed agraz or placebo over 4 weeks; separated by a 4-week washout period. HDL function (apoliprotein-A1; paraoxonase 1 (PON1) activity; cholesterol efflux capacity), oxidative stress (myeloperoxidase (MPO), advanced oxidation protein products) and inflammatory markers (serum cytokines/chemokines and peripheral blood mononuclear cell nuclear factor-kB) were measured after each period. Compared to placebo, agraz consumption did not significantly change any of the biomarkers measured. Interestingly, only after agraz period there were significant positive correlations between PON1 activities and cholesterol efflux. Additionally, there were significant inverse correlations between changes in inflammatory markers and HDL function markers and positive correlations with oxidative markers. Although polyphenol-rich foods have been shown to be beneficial for certain conditions; polyphenol-rich agraz fruit consumption did not impact inflammation and HDL function in the current study of women with MetS.
      Citation: Antioxidants
      PubDate: 2018-12-08
      DOI: 10.3390/antiox7120185
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 186: Mitochondrial Membrane
           Dynamics—Functional Positioning of OPA1

    • Authors: Hakjoo Lee, Yisang Yoon
      First page: 186
      Abstract: The maintenance of mitochondrial energetics requires the proper regulation of mitochondrial morphology, and vice versa. Mitochondrial dynamins control mitochondrial morphology by mediating fission and fusion. One of them, optic atrophy 1 (OPA1), is the mitochondrial inner membrane remodeling protein. OPA1 has a dual role in maintaining mitochondrial morphology and energetics through mediating inner membrane fusion and maintaining the cristae structure. OPA1 is expressed in multiple variant forms through alternative splicing and post-translational proteolytic cleavage, but the functional differences between these variants have not been completely understood. Recent studies generated new information regarding the role of OPA1 cleavage. In this review, we will first provide a brief overview of mitochondrial membrane dynamics by describing fission and fusion that are mediated by mitochondrial dynamins. The second part describes OPA1-mediated fusion and energetic maintenance, the role of OPA1 cleavage, and a new development in OPA1 function, in which we will provide new insight for what OPA1 does and what proteolytic cleavage of OPA1 is for.
      Citation: Antioxidants
      PubDate: 2018-12-08
      DOI: 10.3390/antiox7120186
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 187: Flavonoids and Colorectal Cancer
           Prevention

    • Authors: Yanyan Li, Tao Zhang, Grace Y. Chen
      First page: 187
      Abstract: Colorectal cancer (CRC) is the third most common cancer, but despite advances in treatment, it remains the second most common cause of cancer-related mortality. Prevention may, therefore, be a key strategy in reducing colorectal cancer deaths. Given reports of an inverse association between fruit and vegetable consumption with colorectal cancer risk, there has been significant interest in understanding the metabolism and bioactivity of flavonoids, which are highly abundant in fruits and vegetables and account for their pigmentation. In this review, we discuss host and microbiota-mediated metabolism of flavonoids and the potential mechanisms by which flavonoids can exert protective effects against colon tumorigenesis, including regulation of signaling pathways involved in apoptosis, cellular proliferation, and inflammation and modulation of the gut microbiome.
      Citation: Antioxidants
      PubDate: 2018-12-10
      DOI: 10.3390/antiox7120187
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 188: Novel Docosahexaenoic Acid Ester of
           Phloridzin Inhibits Proliferation and Triggers Apoptosis in an In Vitro
           Model of Skin Cancer

    • Authors: Theodora Mantso, Dimitrios Trafalis, Sotiris Botaitis, Rodrigo Franco, Aglaia Pappa, H. Rupasinghe, Mihalis Panayiotidis
      First page: 188
      Abstract: Skin cancer is among the most common cancer types accompanied by rapidly increasing incidence rates, thus making the development of more efficient therapeutic approaches a necessity. Recent studies have revealed the potential role of decosahexaenoic acid ester of phloridzin (PZDHA) in suppressing proliferation of liver, breast, and blood cancer cell lines. In the present study, we investigated the cytotoxic potential of PZDHA in an in vitro model of skin cancer consisting of melanoma (A375), epidermoid carcinoma (A431), and non-tumorigenic (HaCaT) cell lines. Decosahexaenoic acid ester of phloridzin led to increased cytotoxicity in all cell lines as revealed by cell viability assays. However, growth inhibition and induction of both apoptosis and necrosis was more evident in melanoma (A375) and epidermoid carcinoma (A431) cells, whereas non-tumorigenic keratinocytes (HaCaT) appeared to be more resistant as detected by flow cytometry. More specifically, PZDHA-induced cell cycle growth arrest at the G2/M phase in A375 and A431 cells in contrast to HaCaT cells, which were growth arrested at the G0/G1 phase. Elevated intracellular generation of reactive oxygen species ROS was detected in all cell lines. Overall, our findings support the potential of PZDHA as a novel therapeutic means against human skin cancer.
      Citation: Antioxidants
      PubDate: 2018-12-11
      DOI: 10.3390/antiox7120188
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 189: Far Infrared Irradiation Enhances
           Nutraceutical Compounds and Antioxidant Properties in Angelica gigas Nakai
           Powder

    • Authors: Md Obyedul Kalam Azad, Jing Pei Piao, Cheol Ho Park, Dong Ha Cho
      First page: 189
      Abstract: The aim of this study was to investigate the effect of far infrared irradiation (FIR) on nutraceutical compounds, viz. total phenolic content, total flavonoids, and antioxidant capacity, of Angelica gigas Nakai (AGN). The FIR treatment was applied for 30 min with varied temperatures of 120, 140, 160, 180, 200, 220, and 240 °C. Results showed that FIR increased total phenolic and flavonoid content in AGN at 220 °C. The HPLC results revealed higher quantities of decursin (62.48 mg/g) and decursinol angelate (41.51 mg/g) at 220 °C compared to control (38.70 mg/g, 27.54 mg/g, respectively). The antioxidant capacity of AGN was also increased at 220 °C, as measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and the phosphomolybdenum (PPMD) method. A further increase of the FIR temperature caused a reduction of compound content. In addition, the results also showed a strong correlation between phenolic content and antioxidant properties of AGN powder. These findings will help to further improve the nutraceutical profile of AGN powder by optimizing the FIR conditions.
      Citation: Antioxidants
      PubDate: 2018-12-11
      DOI: 10.3390/antiox7120189
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 190: New Insights into the Potential of
           Endogenous Redox Systems in Wheat Bread Dough

    • Authors: Nicolas Navrot, Rikke Buhl Holstborg, Per Hägglund, Inge Lise Povlsen, Birte Svensson
      First page: 190
      Abstract: Various redox compounds are known to influence the structure of the gluten network in bread dough, and hence its strength. The cereal thioredoxin system (NTS), composed of nicotinamide adenine dinucleotide phosphate (NADPH)-dependent thioredoxin reductase (NTR) and thioredoxin (Trx), is a major reducing enzymatic system that is involved in seed formation and germination. NTS is a particularly interesting tool for food processing due to its heat stability and its broad range of protein substrates. We show here that barley NTS is capable of remodeling the gluten network and weakening bread dough. Furthermore, functional wheat Trx that is present in the dough can be recruited by the addition of recombinant barley NTR, resulting in dough weakening. These results confirm the potential of NTS, especially NTR, as a useful tool in baking for weakening strong doughs, or in flat product baking.
      Citation: Antioxidants
      PubDate: 2018-12-12
      DOI: 10.3390/antiox7120190
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 191: The Oxidized Protein Repair Enzymes
           Methionine Sulfoxide Reductases and Their Roles in Protecting against
           Oxidative Stress, in Ageing and in Regulating Protein Function

    • Authors: Sofia Lourenço dos Santos, Isabelle Petropoulos, Bertrand Friguet
      First page: 191
      Abstract: Cysteine and methionine residues are the amino acids most sensitive to oxidation by reactive oxygen species. However, in contrast to other amino acids, certain cysteine and methionine oxidation products can be reduced within proteins by dedicated enzymatic repair systems. Oxidation of cysteine first results in either the formation of a disulfide bridge or a sulfenic acid. Sulfenic acid can be converted to disulfide or sulfenamide or further oxidized to sulfinic acid. Disulfide can be easily reversed by different enzymatic systems such as the thioredoxin/thioredoxin reductase and the glutaredoxin/glutathione/glutathione reductase systems. Methionine side chains can also be oxidized by reactive oxygen species. Methionine oxidation, by the addition of an extra oxygen atom, leads to the generation of methionine sulfoxide. Enzymatically catalyzed reduction of methionine sulfoxide is achieved by either methionine sulfoxide reductase A or methionine sulfoxide reductase B, also referred as to the methionine sulfoxide reductases system. This oxidized protein repair system is further described in this review article in terms of its discovery and biologically relevant characteristics, and its important physiological roles in protecting against oxidative stress, in ageing and in regulating protein function.
      Citation: Antioxidants
      PubDate: 2018-12-12
      DOI: 10.3390/antiox7120191
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 192: Agrimonia procera Wallr. Extract
           Increases Stress Resistance and Prolongs Life Span in Caenorhabditis
           elegans via Transcription Factor DAF-16 (FoxO Orthologue)

    • Authors: Christina Saier, Inge Gommlich, Volker Hiemann, Sabrina Baier, Karoline Koch, Gert Horn, Tanja Kowalewsky, Jörg Bartelt, Maria Seemann, Wim Wätjen
      First page: 192
      Abstract: Agrimonia procera is a pharmacologically interesting plant which is proposed to protect against various diseases due to its high amount of phytochemicals, e.g., polyphenols. However, in spite of the amount of postulated health benefits, studies concerning the mechanistic effects of Agrimonia procera are limited. Using the nematode Caenorhabditis elegans, we were able to show that an ethanol extract of Agrimonia procera herba (eAE) mediates strong antioxidative effects in the nematode: Beside a strong radical-scavenging activity, eAE reduces accumulation of reactive oxygen species (ROS) accumulation and protects against paraquat-induced oxidative stress. The extract does not protect against amyloid-β-mediated toxicity, but efficiently increases the life span (up to 12.7%), as well as the resistance to thermal stress (prolongation of survival up to 22%), of this model organism. Using nematodes deficient in the forkhead box O (FoxO)-orthologue DAF-16, we were able to demonstrate that beneficial effects of eAE on stress resistance and life span were mediated via this transcription factor. We showed antioxidative, stress-reducing, and life-prolonging effects of eAE in vivo and were able to demonstrate a molecular mechanism of this extract. These results may be important for identifying further molecular targets of eAE in humans.
      Citation: Antioxidants
      PubDate: 2018-12-14
      DOI: 10.3390/antiox7120192
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 193: Oxidative Stress in the Newborn Period:
           Useful Biomarkers in the Clinical Setting

    • Authors: Iván Millán, José David Piñero-Ramos, Inmaculada Lara, Anna Parra-Llorca, Isabel Torres-Cuevas, Máximo Vento
      First page: 193
      Abstract: Aerobic metabolism is highly efficient in providing energy for multicellular organisms. However, even under physiological conditions, an incomplete reduction of oxygen produces reactive oxygen species and, subsequently, oxidative stress. Some of these chemical species are highly reactive free radicals capable of causing functional and structural damage to cell components (protein, lipids, or nucleotides). Oxygen is the most used drug in ill-adapted patients during the newborn period. The use of oxygen may cause oxidative stress-related diseases that increase mortality and cause morbidity with adverse long-term outcomes. Conditions such as prematurity or birth asphyxia are frequently treated with oxygen supplementation. Both pathophysiological situations of hypoxia–reoxygenation in asphyxia and hyperoxia in premature infants cause a burst of reactive oxygen species and oxidative stress. Recently developed analytical assays using mass spectrometry have allowed us to determine highly specific biomarkers with minimal samples. The detection of these metabolites will help improve the diagnosis, evolution, and response to therapy in oxidative stress-related conditions during the newborn period.
      Citation: Antioxidants
      PubDate: 2018-12-14
      DOI: 10.3390/antiox7120193
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 194: Suppressing Effect of 2-Nitrobenzaldehyde
           on Singlet Oxygen Generation, Fatty Acid Photooxidation, and
           Dye-Sensitizer Degradation

    • Authors: Mahdi Hajimohammadi, Atena Vaziri Sereshk, Clemens Schwarzinger, Günther Knör
      First page: 194
      Abstract: 2-Nitrobenzaldehyde was found to efficiently block singlet oxygen generation in a series of different test samples upon exposure to UV and visible light under aerobic conditions. The effect of quenching singlet oxygen formation was monitored in the presence of 1, 4-diazabicyclo [2.2.2] octane (DABCO) acting as a well-known singlet oxygen scavenger. A comparison of different nitrobenzaldehyde isomers with other highly effective synthetic antioxidants used in the food industry such as butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), tert-butylhydroquinone (TBHQ) revealed that the protection of materials from singlet oxygen decreases in the order of 2-nitrobenzaldehyde > DABCO > TBHQ > 3-nitrobenzaldehyde > BHA > 4-nitrobenzaldehyde > BHT. Upon addition of 2-nitrobenzaldehyde, the oxidation of fatty acids and the degradation of photosensitizers was found to be considerably diminished, which indicates that the presence of 2-nitrobenzaldehyde has a significant protective influence by restricting the singlet oxygen generation and photodegradation of dyes. Moreover, the compound turned out to display its highly suppressing effects on typical singlet oxygen-dependent reactions, such as fatty acid photooxidation and dye photosensitizer degradation, in a rather broad spectral region covering wavelengths from 300 nm (UV-B) to 575 nm (close to the maximum of ambient solar radiation).
      Citation: Antioxidants
      PubDate: 2018-12-18
      DOI: 10.3390/antiox7120194
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 195: Adrenergic Regulation of Drp1-Driven
           Mitochondrial Fission in Cardiac Physio-Pathology

    • Authors: Bong Sook Jhun, Jin O-Uchi, Stephanie M. Adaniya, Michael W. Cypress, Yisang Yoon
      First page: 195
      Abstract: Abnormal mitochondrial morphology, especially fragmented mitochondria, and mitochondrial dysfunction are hallmarks of a variety of human diseases including heart failure (HF). Although emerging evidence suggests a link between mitochondrial fragmentation and cardiac dysfunction, it is still not well described which cardiac signaling pathway regulates mitochondrial morphology and function under pathophysiological conditions such as HF. Mitochondria change their shape and location via the activity of mitochondrial fission and fusion proteins. This mechanism is suggested as an important modulator for mitochondrial and cellular functions including bioenergetics, reactive oxygen species (ROS) generation, spatiotemporal dynamics of Ca2+ signaling, cell growth, and death in the mammalian cell- and tissue-specific manners. Recent reports show that a mitochondrial fission protein, dynamin-like/related protein 1 (DLP1/Drp1), is post-translationally modified via cell signaling pathways, which control its subcellular localization, stability, and activity in cardiomyocytes/heart. In this review, we summarize the possible molecular mechanisms for causing post-translational modifications (PTMs) of DLP1/Drp1 in cardiomyocytes, and further discuss how these PTMs of DLP1/Drp1 mediate abnormal mitochondrial morphology and mitochondrial dysfunction under adrenergic signaling activation that contributes to the development and progression of HF.
      Citation: Antioxidants
      PubDate: 2018-12-18
      DOI: 10.3390/antiox7120195
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 196: Monocyte Subsets in Atherosclerosis and
           Modification with Exercise in Humans

    • Authors: Ning Aw, Elisa Canetti, Katsuhiko Suzuki, Jorming Goh
      First page: 196
      Abstract: Atherosclerosis is a progressive pathological remodeling of the arteries and one of its hallmarks is the presence of chronic inflammation. Notably, there is an increased proportion and activation state of specific monocyte subsets in systemic blood circulation. Monocyte subsets have distinct contributions to the formation, progression, and destabilization of the atherosclerotic plaque. Strong clinical and epidemiological studies show that regular aerobic exercise mitigates the progression of cardiovascular disease. In fact, aerobic fitness is a powerful predictor of cardiovascular mortality in adults, independent of traditional risk factors such as hypertension and hyperlipidemia. Acute bouts and chronic exercise training modulate monocyte behavior, ranging from their recruitment from the bone marrow or marginal pool, to tissue margination and functional changes in cytokine and chemokine production. Such modulation could reflect a potential mechanism for the cardio-protective effect of exercise on atherosclerosis. This review summarizes the current knowledge of monocyte subsets and highlights what is known about their responses to exercise.
      Citation: Antioxidants
      PubDate: 2018-12-19
      DOI: 10.3390/antiox7120196
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 197: New Lipophenol Antioxidants Reduce
           Oxidative Damage in Retina Pigment Epithelial Cells

    • Authors: Espérance Moine, Philippe Brabet, Laurent Guillou, Thierry Durand, Joseph Vercauteren, Céline Crauste
      First page: 197
      Abstract: Age-related macular degeneration (AMD) is a multifactorial pathology and its progression is exacerbated by oxidative stress. Oxidation and photo-oxidation reactions modify lipids in retinal cells, contribute to tissue injury, and lead to the formation of toxic adducts. In particular, autofluorescent pigments such as N-retinylidene-N-retinylethanolamine (A2E) accumulate as lipofuscin in retinal pigment epithelial cells, contribute to the production of additional reactive oxygen species (ROS), and lead to cell degeneration. In an effort to develop efficient antioxidants to reduce damage caused by lipid oxidation, various natural polyphenols were structurally modified to increase their lipophilicity (lipophenols). In this study, resveratrol, phloroglucinol, quercetin and catechin were selected and conjugated to various polyunsaturated fatty acids (PUFAs) using classical chemical strategies or enzymatic reactions. After screening for cytotoxicity, the capacity of the synthesized lipophenols to reduce ROS production was evaluated in ARPE-19 cells subjected to H2O2 treatment using a dichlorofluorescein diacetate probe. The positions of the PUFA on the polyphenol core appear to influence the antioxidant effect. In addition, two lipophenolic quercetin derivatives were evaluated to highlight their potency in protecting ARPE-19 cells against A2E photo-oxidation toxicity. Quercetin conjugated to linoleic or α-linolenic acid were promising lipophilic antioxidants, as they protected ARPE-19 cells from A2E-induced cell death more effectively than the parent polyphenol, quercetin.
      Citation: Antioxidants
      PubDate: 2018-12-19
      DOI: 10.3390/antiox7120197
      Issue No: Vol. 7, No. 12 (2018)
       
  • Antioxidants, Vol. 7, Pages 149: Heat Sepsis Precedes Heat Toxicity in the
           Pathophysiology of Heat Stroke—A New Paradigm on an Ancient Disease

    • Authors: Chin Leong Lim
      First page: 149
      Abstract: Heat stroke (HS) is an ancient illness dating back more than 2000 years and continues to be a health threat and to cause fatality during physical exertion, especially in military personnel, fire-fighters, athletes, and outdoor laborers. The current paradigm in the pathophysiology and prevention of HS focuses predominantly on heat as the primary trigger and driver of HS, which has not changed significantly for centuries. However, pathological and clinical reports from HS victims and research evidence from animal and human studies support the notion that heat alone does not fully explain the pathophysiology of HS and that HS may also be triggered and driven by heat- and exercise-induced endotoxemia. Exposure to heat and exercise stresses independently promote the translocation of lipopolysaccharides (LPS) from gram-negative bacteria in the gut to blood in the circulatory system. Blood concentration of LPS can increase to a threshold that triggers the systemic inflammatory response, leading to the downstream ramifications of cellular and organ damage with sepsis as the end point i.e., heat sepsis. The dual pathway model (DPM) of HS proposed that HS is triggered by two independent pathways sequentially along the core temperature continuum of >40 °C. HS is triggered by heat sepsis at Tc < 42 °C and by the heat toxicity at Tc > 42 °C, where the direct effects of heat alone can cause cellular and organ damage. Therefore, heat sepsis precedes heat toxicity in the pathophysiology of HS.
      Citation: Antioxidants
      PubDate: 2018-10-25
      DOI: 10.3390/antiox7110149
      Issue No: Vol. 7, No. 11 (2018)
       
  • Antioxidants, Vol. 7, Pages 150: Effects of Bcl-2/Bcl-xL Inhibitors on
           Pulmonary Artery Smooth Muscle Cells

    • Authors: Vladyslava Rybka, Yuichiro J. Suzuki, Nataliia V. Shults
      First page: 150
      Abstract: Pulmonary arterial hypertension (PAH) is a fatal disease without satisfactory therapeutic options. By the time patients are diagnosed with this disease, the remodeling of pulmonary arteries has already developed due to the abnormal growth of pulmonary vascular cells. Therefore, agents that reduce excess pulmonary vascular cells have therapeutic potential. Bcl-2 is known to function in an antioxidant pathway to prevent apoptosis. The present study examined the effects of inhibitors of the anti-apoptotic proteins Bcl-2 and Bcl-xL. ABT-263 (Navitoclax), ABT-199 (Venetoclax), ABT-737, and Obatoclax, which all promoted the death of cultured human pulmonary artery smooth muscle cells. Further examinations using ABT-263 showed that Bcl-2/Bcl-xL inhibition indeed promoted apoptotic programmed cell death. ABT-263-induced cell death was inhibited by antioxidants. ABT-263 also promoted autophagy; however, the inhibition of autophagy did not suppress ABT-263-induced cell death. This is in contrast to other previously studied drugs, including anthracyclines and proteasome inhibitors, which were found to mediate autophagy to induce cell death. The administration of ABT-263 to rats with PAH in vivo resulted in the reversal of pulmonary vascular remodeling. Thus, promoting apoptosis by inhibiting anti-apoptotic Bcl-2 and Bcl-xL effectively kills pulmonary vascular smooth muscle cells and reverses pulmonary vascular remodeling.
      Citation: Antioxidants
      PubDate: 2018-10-26
      DOI: 10.3390/antiox7110150
      Issue No: Vol. 7, No. 11 (2018)
       
  • Antioxidants, Vol. 7, Pages 151: Hmox1 Upregulation Is a Mutual Marker in
           Human Tumor Cells Exposed to Physical Plasma-Derived Oxidants

    • Authors: Sander Bekeschus, Eric Freund, Kristian Wende, Rajesh Kumar Gandhirajan, Anke Schmidt
      First page: 151
      Abstract: Increasing numbers of cancer deaths worldwide demand for new treatment avenues. Cold physical plasma is a partially ionized gas expelling a variety of reactive oxygen and nitrogen species, which can be harnesses therapeutically. Plasmas and plasma-treated liquids have antitumor properties in vitro and in vivo. Yet, global response signatures to plasma treatment have not yet been identified. To this end, we screened eight human cancer cell lines to investigate effects of low-dose, tumor-static plasma-treated medium (PTM) on cellular activity, immune-modulatory properties, and transcriptional levels of 22 redox-related genes. With PTM, a moderate reduction of metabolic activity and modest modulation of chemokine/cytokine pattern and markers of immunogenic cell death was observed. Strikingly, the Nuclear factor (erythroid-derived 2)-like 2 (nrf2) target heme oxygenase 1 (hmox1) was upregulated in all cell lines 4 h post PTM-treatment. nrf2 was not changed, but its baseline expression inversely and significantly correlated with hmox1 expression after exposure to PTM. Besides awarding hmox1 a central role with plasma-derived oxidants, we present a transcriptional redox map of 22 targets and chemokine/cytokine secretion map of 13 targets across eight different human tumor cell lines of four tumor entities at baseline activity that are useful for future studies in this field.
      Citation: Antioxidants
      PubDate: 2018-10-27
      DOI: 10.3390/antiox7110151
      Issue No: Vol. 7, No. 11 (2018)
       
  • Antioxidants, Vol. 7, Pages 152: Towards Initial Indications for a
           Thiol-Based Redox Control of Arabidopsis 5-Aminolevulinic Acid Dehydratase
           

    • Authors: Daniel Wittmann, Sigri Kløve, Peng Wang, Bernhard Grimm
      First page: 152
      Abstract: Thiol-based redox control is one of the important posttranslational mechanisms of the tetrapyrrole biosynthesis pathway. Many enzymes of the pathway have been shown to interact with thioredoxin (TRX) and Nicotinamide adenine dinucleotide phosphate (NADPH)-dependent thioredoxin reductase C (NTRC). We examined the redox-dependency of 5-aminolevulinic acid dehydratase (ALAD), which catalyzed the conjugation of two 5-aminolevulinic acid (ALA) molecules to porphobilinogen. ALAD interacted with TRX f, TRX m and NTRC in chloroplasts. Consequently, less ALAD protein accumulated in the trx f1, ntrc and trx f1/ntrc mutants compared to wild-type control resulting in decreased ALAD activity. In a polyacrylamide gel under non-reducing conditions, ALAD monomers turned out to be present in reduced and two oxidized forms. The reduced and oxidized forms of ALAD differed in their catalytic activity. The addition of TRX stimulated ALAD activity. From our results it was concluded that (i) deficiency of the reducing power mainly affected the in planta stability of ALAD; and (ii) the reduced form of ALAD displayed increased enzymatic activity.
      Citation: Antioxidants
      PubDate: 2018-10-31
      DOI: 10.3390/antiox7110152
      Issue No: Vol. 7, No. 11 (2018)
       
  • Antioxidants, Vol. 7, Pages 153: Determining the Rate-Limiting Step for
           Light-Responsive Redox Regulation in Chloroplasts

    • Authors: Keisuke Yoshida, Toru Hisabori
      First page: 153
      Abstract: Thiol-based redox regulation ensures light-responsive control of chloroplast functions. Light-derived signal is transferred in the form of reducing power from the photosynthetic electron transport chain to several redox-sensitive target proteins. Two types of protein, ferredoxin-thioredoxin reductase (FTR) and thioredoxin (Trx), are well recognized as the mediators of reducing power. However, it remains unclear which step in a series of redox-relay reactions is the critical bottleneck for determining the rate of target protein reduction. To address this, the redox behaviors of FTR, Trx, and target proteins were extensively characterized in vitro and in vivo. The FTR/Trx redox cascade was reconstituted in vitro using recombinant proteins from Arabidopsis. On the basis of this assay, we found that the FTR catalytic subunit and f-type Trx are rapidly reduced after the drive of reducing power transfer, irrespective of the presence or absence of their downstream target proteins. By contrast, three target proteins, fructose 1,6-bisphosphatase (FBPase), sedoheptulose 1,7-bisphosphatase (SBPase), and Rubisco activase (RCA) showed different reduction patterns; in particular, SBPase was reduced at a low rate. The in vivo study using Arabidopsis plants showed that the Trx family is commonly and rapidly reduced upon high light irradiation, whereas FBPase, SBPase, and RCA are differentially and slowly reduced. Both of these biochemical and physiological findings suggest that reducing power transfer from Trx to its target proteins is a rate-limiting step for chloroplast redox regulation, conferring distinct light-responsive redox behaviors on each of the targets.
      Citation: Antioxidants
      PubDate: 2018-10-31
      DOI: 10.3390/antiox7110153
      Issue No: Vol. 7, No. 11 (2018)
       
  • Antioxidants, Vol. 7, Pages 154: Antioxidant Activities of Dialium indum
           L. Fruit and Gas Chromatography-Mass Spectrometry (GC-MS) of the Active
           Fractions

    • Authors: Muhamad Faris Osman, Norazian Mohd Hassan, Alfi Khatib, Siti Marponga Tolos
      First page: 154
      Abstract: The fruit of Dialium indum L. (Fabaceae) is one of the edible wild fruits native to Southeast Asia. The mesocarp is consumed as sweets while the exocarp and seed are regarded as waste. This study aimed to evaluate the antioxidant activities of the fruit by using four assays, which measure its capabilities in reducing phosphomolybdic-phosphotungstic acid reagents, neocuproine, 2,2-diphenyl-picrylhydrazyl (DPPH), and inhibiting linoleic acid peroxidation. The active fractions were then analyzed by gas chromatography-mass spectrometry (GC-MS). The results showed that the seed methanol fraction (SMF) exhibited the strongest antioxidant activity with significantly higher (p < 0.05) gallic acid equivalence (GAE), total antioxidant capacity (TAC), and DPPH radical scavenging activity (IC50 31.71; 0.88 µg/mL) than the other fractions. The exocarp dichloromethane fraction (EDF) was the discriminating fraction by having remarkable linoleic acid peroxidation inhibition (IC50 121.43; 2.97 µg/mL). A total of thirty-eight metabolites were detected in derivatized EDF and SMF with distinctive classes of phenolics and amino acids, respectively. Bioautography-guided fractionation of EDF afforded five antioxidant-enriched subfractions with four other detected phenolics. The results revealed the antioxidant properties of D. indum fruit, which has potential benefits in pharmaceutical, nutraceutical, and cosmeceutical applications.
      Citation: Antioxidants
      PubDate: 2018-11-01
      DOI: 10.3390/antiox7110154
      Issue No: Vol. 7, No. 11 (2018)
       
  • Antioxidants, Vol. 7, Pages 155: In Vivo Effects of Methionine Sulfoxide
           Reductase Deficiency in Drosophila melanogaster

    • Authors: Lindsay Bruce, Diana Singkornrat, Kelsey Wilson, William Hausman, Kelli Robbins, Lingxi Huang, Katie Foss, David Binninger
      First page: 155
      Abstract: The deleterious alteration of protein structure and function due to the oxidation of methionine residues has been studied extensively in age-associated neurodegenerative disorders such as Alzheimer’s and Parkinson’s Disease. Methionine sulfoxide reductases (MSR) have three well-characterized biological functions. The most commonly studied function is the reduction of oxidized methionine residues back into functional methionine thus, often restoring biological function to proteins. Previous studies have successfully overexpressed and silenced MSR activity in numerous model organisms correlating its activity to longevity and oxidative stress. In the present study, we have characterized in vivo effects of MSR deficiency in Drosophila. Interestingly, we found no significant phenotype in animals lacking either methionine sulfoxide reductase A (MSRA) or methionine sulfoxide reductase B (MSRB). However, Drosophila lacking any known MSR activity exhibited a prolonged larval third instar development and a shortened lifespan. These data suggest an essential role of MSR in key biological processes.
      Citation: Antioxidants
      PubDate: 2018-11-01
      DOI: 10.3390/antiox7110155
      Issue No: Vol. 7, No. 11 (2018)
       
  • Antioxidants, Vol. 7, Pages 156: Superoxide Dismutases (SODs) and SOD
           Mimetics

    • Authors: Gloria E. O. Borgstahl, Rebecca E. Oberley-Deegan
      First page: 156
      Abstract: Superoxide dismutase (SOD) is the only known enzyme to directly scavenge a free radical. [...]
      Citation: Antioxidants
      PubDate: 2018-11-02
      DOI: 10.3390/antiox7110156
      Issue No: Vol. 7, No. 11 (2018)
       
  • Antioxidants, Vol. 7, Pages 157: Oxygen and Glucose Levels in Cell Culture
           Media Determine Resveratrol’s Effects on Growth, Hydrogen Peroxide
           Production, and Mitochondrial Dynamics

    • Authors: Joao Fonseca, Fereshteh Moradi, Andrew J. F. Valente, Jeffrey A. Stuart
      First page: 157
      Abstract: Resveratrol is a plant-derived polyphenol that has been widely studied for its putative health promoting effects. Many of those studies have been conducted in cell culture, in supra-physiological levels of oxygen and glucose. Resveratrol interacts with reactive oxygen species (ROS) as an antioxidant or pro-oxidant. Resveratrol affects the expression and activities of ROS-producing enzymes and organelles. It is therefore important to consider how cell culture conditions might determine the effects of resveratrol on cultured cells. We determined the effects of resveratrol on cell growth, hydrogen peroxide production, and mitochondrial network characteristics in C2C12 mouse myoblasts and PC3 human prostate cancer cells under conditions of physiological (5%) and supra-physiological (18%) oxygen, and normo- (5 mM) and hyper-glycemia (25 mM). Interestingly, most effects of resveratrol on the parameters measured here were dependent upon prevailing oxygen and glucose levels during the experiment. Many of the effects of resveratrol on cell growth, hydrogen peroxide production, and mitochondrial network characteristics that were seen in 25 mM glucose and/or 18% oxygen were absent under the physiologically relevant conditions of 5 mM glucose with 5% oxygen. These findings emphasize the importance of using physiologically meaningful starting conditions for cell-culture experiments with resveratrol and indeed any manipulation affecting ROS metabolism and mitochondria.
      Citation: Antioxidants
      PubDate: 2018-11-05
      DOI: 10.3390/antiox7110157
      Issue No: Vol. 7, No. 11 (2018)
       
  • Antioxidants, Vol. 7, Pages 158: Antioxidants and Second Messengers of
           Free Radicals

    • Authors: Neven Zarkovic
      First page: 158
      Abstract: In the recent years, numerous research on the pathology of oxidative stress has been completed by intense studies on redox signaling implementing various experimental models and clinical trials. [...]
      Citation: Antioxidants
      PubDate: 2018-11-06
      DOI: 10.3390/antiox7110158
      Issue No: Vol. 7, No. 11 (2018)
       
  • Antioxidants, Vol. 7, Pages 159: Hydrogen Peroxide and Redox Regulation of
           Developments

    • Authors: Christine Rampon, Michel Volovitch, Alain Joliot, Sophie Vriz
      First page: 159
      Abstract: Reactive oxygen species (ROS), which were originally classified as exclusively deleterious compounds, have gained increasing interest in the recent years given their action as bona fide signalling molecules. The main target of ROS action is the reversible oxidation of cysteines, leading to the formation of disulfide bonds, which modulate protein conformation and activity. ROS, endowed with signalling properties, are mainly produced by NADPH oxidases (NOXs) at the plasma membrane, but their action also involves a complex machinery of multiple redox-sensitive protein families that differ in their subcellular localization and their activity. Given that the levels and distribution of ROS are highly dynamic, in part due to their limited stability, the development of various fluorescent ROS sensors, some of which are quantitative (ratiometric), represents a clear breakthrough in the field and have been adapted to both ex vivo and in vivo applications. The physiological implication of ROS signalling will be presented mainly in the frame of morphogenetic processes, embryogenesis, regeneration, and stem cell differentiation. Gain and loss of function, as well as pharmacological strategies, have demonstrated the wide but specific requirement of ROS signalling at multiple stages of these processes and its intricate relationship with other well-known signalling pathways.
      Citation: Antioxidants
      PubDate: 2018-11-06
      DOI: 10.3390/antiox7110159
      Issue No: Vol. 7, No. 11 (2018)
       
  • Antioxidants, Vol. 7, Pages 160: Comparative Effects of Coenzyme Q10 or
           n-3 Polyunsaturated Fatty Acid Supplementation on Retinal Angiogenesis in
           a Rat Model of Oxygen-Induced Retinopathy

    • Authors: Kay D. Beharry, Charles L. Cai, Faisal Siddiqui, Sara Chowdhury, Christina D’Agrosa, Gloria B. Valencia, Jacob V. Aranda
      First page: 160
      Abstract: Neonatal intermittent hypoxia (IH) or apnea afflicts 70% to 90% of all preterm infants <28 weeks gestation, and is associated with severe retinopathy of prematurity (ROP). We tested the hypotheses that coenzyme Q10 (CoQ10) or omega-3 polyunsaturated fatty acids (n-3 PUFAs) supplementation during neonatal IH reduces the severity of oxygen-induced retinopathy (OIR). Newborn rats were exposed to two IH paradigms: (1) 50% O2 with brief hypoxia (12% O2); or (2) 21% O2 with brief hypoxia, until postnatal day 14 (P14), during which they received daily oral CoQ10 in olive oil, n-3 PUFAs in fish oil, or olive oil only and compared to room air (RA) treated groups. Pups were examined at P14, or placed in RA until P21. Retinal angiogenesis, histopathology, and morphometry were determined. Both IH paradigms produced severe OIR, but these were worsened with 50/12% O2 IH. CoQ10 and n-3 PUFAs reduced the severity of OIR, as well as ocular growth factors in both IH paradigms, but CoQ10 was more effective in 50/12% O2 IH. Supplementation with either CoQ10 or n-3 PUFAs targeting IH-induced retinal injury is individually effective for ameliorating specific characteristics consistent with ROP. Given the complexity of ROP, further studies are needed to determine whether combined CoQ10 and n-3 PUFAs supplementation would optimize their efficacy and result in a better outcome.
      Citation: Antioxidants
      PubDate: 2018-11-09
      DOI: 10.3390/antiox7110160
      Issue No: Vol. 7, No. 11 (2018)
       
  • Antioxidants, Vol. 7, Pages 161: Cancer-Associated Function of 2-Cys
           Peroxiredoxin Subtypes as a Survival Gatekeeper

    • Authors: Sang Won Kang, Sunmi Lee, Joanna H. S. Lee
      First page: 161
      Abstract: Cancer cells are abnormal cells that do not comply with tissue homeostasis but undergo uncontrolled proliferation. Such abnormality is driven mostly by somatic mutations on oncogenes and tumor suppressors. Cancerous mutations show intra-tumoral heterogeneity across cancer types and eventually converge into the self-activation of proliferative signaling. While transient production of intracellular reactive oxygen species (ROS) is essential for cell signaling, its persistent production is cytotoxic. Thus, cancer cells require increased levels of intracellular ROS for continuous proliferation, but overexpress cellular peroxidase enzymes, such as 2-Cys peroxiredoxins, to maintain ROS homeostasis. However, suppression of 2-Cys peroxiredoxins has also been reported in some metastatic cancers. Hence, the cancer-associated functions of 2-Cys peroxiredoxins must be illuminated in the cellular context. In this review, we describe the distinctive signaling roles of 2-Cys peroxiredoxins beyond their intrinsic ROS-scavenging role in relation to cancer cell death and survival.
      Citation: Antioxidants
      PubDate: 2018-11-11
      DOI: 10.3390/antiox7110161
      Issue No: Vol. 7, No. 11 (2018)
       
  • Antioxidants, Vol. 7, Pages 162: Exercise and Redox Status Responses
           

    • Authors: Kalliopi Georgakouli, Ioannis G. Fatouros, Apostolos Fragkos, Theofanis Tzatzakis, Chariklia K. Deli, Konstantinos Papanikolaou, Yiannis Koutedakis, Athanasios Z. Jamurtas
      First page: 162
      Abstract: G6PD deficiency renders cells more susceptible to oxidative insults, while antioxidant dietary supplementation could restore redox balance and ameliorate exercise-induced oxidative stress. To examine the effects of alpha-lipoic acid (ALA) supplementation on redox status indices in G6PD deficient individuals, eight male adults with G6PD deficiency (D) participated in this randomized double-blind placebo-controlled crossover trial. Participants were randomly assigned to receive ALA (600 mg/day) or placebo for 4 weeks separated by a 4-week washout period. Before and at the end of each treatment period, participants exercised following an exhaustive treadmill exercise protocol. Blood samples were obtained before (at rest), immediately after and 1h after exercise for later analysis of total antioxidant capacity (TAC), uric acid, bilirubin, thiobarbituric acid reactive substances (TBARS) and protein carbonyls (PC). ALA resulted in significantly increased resting TAC and bilirubin concentrations. Moreover, TAC increased immediately and 1h after exercise following both treatment periods, whereas bilirubin increased immediately after and 1h after exercise following only ALA. No significant change in uric acid, TBARS or PC was observed at any time point. ALA supplementation for 4 weeks may enhance antioxidant status in G6PD individuals; however, it does not affect redox responses to acute exercise until exhaustion or exercise performance.
      Citation: Antioxidants
      PubDate: 2018-11-12
      DOI: 10.3390/antiox7110162
      Issue No: Vol. 7, No. 11 (2018)
       
  • Antioxidants, Vol. 7, Pages 163: Production of a Novel Functional Fruit
           Beverage Consisting of Cornelian Cherry Juice and Probiotic Bacteria

    • Authors: Ioanna Mantzourani, Chryssa Nouska, Antonia Terpou, Athanasios Alexopoulos, Eugenia Bezirtzoglou, Mihalis I. Panayiotidis, Alexis Galanis, Stavros Plessas
      First page: 163
      Abstract: The present study describes the development of a novel functional beverage through the application of probiotic Lactobacillus plantarum ATCC (American Type Culture Collection) 14917 in Cornelian cherry juice fermentation. The probiotic was employed in free and immobilized in a delignified wheat bran carrier (DWB) form. Cornelian cherry juice was fermented for 24 h and then it was stored at 4 °C for 4 weeks. Several parameters were evaluated such as residual sugar, organic acid and alcohol levels, total phenolics content, and cell viability as well as consumers acceptance. Regarding sugar and organic acids analyses, it was proved that the probiotic free or immobilized biocatalyst was effective. The concentration of ethanol was maintained at low levels (0.3–0.9% v/v). The total phenolic content of fermented Cornelian cherry juice with immobilized cells was recorded in higher levels (214–264 mg GAE/100 mL) for all the cold storage time compared to fermented juice with free cells (165–199 mg GAE/100 mL) and non-fermented juice (135–169 mg GAE/100 mL). Immobilized cells retained their viability in higher levels (9.95 log cfu/mL at the 4th week) compared to free cells (7.36 log cfu/mL at the 4th week). No significant sensory differences were observed among the fermented and the non-fermented samples.
      Citation: Antioxidants
      PubDate: 2018-11-12
      DOI: 10.3390/antiox7110163
      Issue No: Vol. 7, No. 11 (2018)
       
  • Antioxidants, Vol. 7, Pages 164: Characterization of TrxC, an Atypical
           Thioredoxin Exclusively Present in Cyanobacteria

    • Authors: Luis López-Maury, Luis G. Heredia-Martínez, Francisco J. Florencio
      First page: 164
      Abstract: Cyanobacteria form a diverse group of oxygenic photosynthetic prokaryotes considered to be the antecessor of plant chloroplast. They contain four different thioredoxins isoforms, three of them corresponding to m, x and y type present in plant chloroplast, while the fourth one (named TrxC) is exclusively found in cyanobacteria. TrxC has a modified active site (WCGLC) instead of the canonical (WCGPC) present in most thioredoxins. We have purified it and assayed its activity but surprisingly TrxC lacked all the classical activities, such as insulin precipitation or activation of the fructose-1,6-bisphosphatase. Mutants lacking trxC or over-expressing it were generated in the model cyanobacterium Synechocystis sp. PCC 6803 and their phenotypes have been analyzed. The ΔtrxC mutant grew at similar rates to WT in all conditions tested although it showed an increased carotenoid content especially under low carbon conditions. Overexpression strains showed reduced growth under the same conditions and accumulated lower amounts of carotenoids. They also showed lower oxygen evolution rates at high light but higher Fv’/Fm’ and Non-photochemical-quenching (NPQ) in dark adapted cells, suggesting a more oxidized plastoquinone pool. All these data suggest that TrxC might have a role in regulating photosynthetic adaptation to low carbon and/or high light conditions.
      Citation: Antioxidants
      PubDate: 2018-11-13
      DOI: 10.3390/antiox7110164
      Issue No: Vol. 7, No. 11 (2018)
       
  • Antioxidants, Vol. 7, Pages 165: Structural/Functional Matches and
           Divergences of Phytoprostanes and Phytofurans with Bioactive Human
           Oxylipins

    • Authors: Sonia Medina, Ángel Gil-Izquierdo, Thierry Durand, Federico Ferreres, Raúl Domínguez-Perles
      First page: 165
      Abstract: Structure-activity relationship (SAR) constitutes a crucial topic to discover new bioactive molecules. This approach initiates with the comparison of a target candidate with a molecule or a collection of molecules and their attributed biological functions to shed some light in the details of one or more SARs and subsequently using that information to outline valuable application of the newly identified compounds. Thus, while the empiric knowledge of medicinal chemistry is critical to these tasks, the results retrieved upon dedicated experimental demonstration retrieved resorting to modern high throughput analytical approaches and techniques allow to overwhelm the constraints adduced so far to the successful accomplishment of such tasks. Therefore, the present work reviews critically the evidences reported to date on the occurrence of phytoprostanes and phytofurans in plant foods, and the information available on their bioavailability and biological activity, shedding some light on the expectation waken up due to their structural similarities with prostanoids and isoprostanes.
      Citation: Antioxidants
      PubDate: 2018-11-16
      DOI: 10.3390/antiox7110165
      Issue No: Vol. 7, No. 11 (2018)
       
  • Antioxidants, Vol. 7, Pages 166: Crystal Structure of the Apo-Form of
           NADPH-Dependent Thioredoxin Reductase from a Methane-Producing Archaeon

    • Authors: Rubén M. Buey, Ruth A. Schmitz, Bob B. Buchanan, Monica Balsera
      First page: 166
      Abstract: The redox regulation of proteins via reversible dithiol/disulfide exchange reactions involves the thioredoxin system, which is composed of a reductant, a thioredoxin reductase (TR), and thioredoxin (Trx). In the pyridine nucleotide-dependent Trx reduction pathway, reducing equivalents, typically from reduced nicotinamide adenine dinucleotide phosphate (NADPH), are transferred from NADPH-TR (NTR) to Trx and, in turn, to target proteins, thus resulting in the reversible modification of the structural and functional properties of the targets. NTR enzymes contain three functional sites: an NADPH binding pocket, a non-covalently bound flavin cofactor, and a redox-active disulfide in the form of CxxC. With the aim of increasing our knowledge of the thioredoxin system in archaea, we here report the high-resolution crystal structure of NTR from the methane-generating organism Methanosarcina mazei strain Gö1 (MmNTR) at 2.6 Å resolution. Based on the crystals presently described, MmNTR assumes an overall fold that is nearly identical to the archetypal fold of authentic NTRs; however, surprisingly, we observed no electron density for flavin adenine dinucleotide (FAD) despite the well-defined and conserved FAD-binding cavity in the folded module. Remarkably, the dimers of the apo-protein within the crystal were different from those observed by small angle X-ray scattering (SAXS) for the holo-protein, suggesting that the binding of the flavin cofactor does not require major protein structural rearrangements. Rather, binding results in the stabilization of essential parts of the structure, such as those involved in dimer stabilization. Altogether, this structure represents the example of an apo-form of an NTR that yields important insight into the effects of the cofactor on protein folding.
      Citation: Antioxidants
      PubDate: 2018-11-17
      DOI: 10.3390/antiox7110166
      Issue No: Vol. 7, No. 11 (2018)
       
  • Antioxidants, Vol. 7, Pages 167: GPX1 Localizes to the Nucleus in Prostate
           Epithelium and its Levels are not Associated with Prostate Cancer
           Recurrence

    • Authors: Dede N. Ekoue, Emmanuel Ansong, Lenny K. Hong, Larisa Nonn, Virgilia Macias, Ryan Deaton, Rawan Rupnow, Peter H. Gann, Andre Kajdacsy-Balla, Alan M. Diamond
      First page: 167
      Abstract: Glutathione peroxidase 1 (GPX1) is an extensively studied selenium-dependent protein that reduces hydrogen and lipid peroxides to water. Because of its antioxidant function and its responsiveness to dietary intakes of selenium, an essential trace element whose levels are inversely associated with prostate cancer risk, GPX1 levels were assessed in a prostate cancer tissue microarray, comparing cases of recurrent prostate cancer following prostatectomy to non-recurrent controls. While GPX1 is generally considered as a protein that resides in both the cytoplasm and mitochondria, we detected strong nuclear staining by immunofluorescence using GPX1-specific antibodies. Nuclear localization of GPX1 was also observed in both primary prostate epithelial cells and the immortalized prostate-derived cell line RWPE-1, but not in LNCaP or PC3 prostate tumor-derived cell lines. Quantification of GPX1 levels in the entire cell, the cytoplasm, and the nucleus did not indicate any association of either its levels or subcellular distribution with prostate cancer recurrence. While GPX1 levels may not have an impact on survival among men with prostate cancer, the data indicates that this extensively characterized protein may have a novel function in the nucleus of prostate epithelial cells.
      Citation: Antioxidants
      PubDate: 2018-11-18
      DOI: 10.3390/antiox7110167
      Issue No: Vol. 7, No. 11 (2018)
       
  • Antioxidants, Vol. 7, Pages 168: The Plasma Membrane: A Platform for
           Intra- and Intercellular Redox Signaling

    • Authors: Daniela E. Nordzieke, Iria Medraño-Fernandez
      First page: 168
      Abstract: Membranes are of outmost importance to allow for specific signal transduction due to their ability to localize, amplify, and direct signals. However, due to the double-edged nature of reactive oxygen species (ROS)—toxic at high concentrations but essential signal molecules—subcellular localization of ROS-producing systems to the plasma membrane has been traditionally regarded as a protective strategy to defend cells from unwanted side-effects. Nevertheless, specialized regions, such as lipid rafts and caveolae, house and regulate the activated/inhibited states of important ROS-producing systems and concentrate redox targets, demonstrating that plasma membrane functions may go beyond acting as a securing lipid barrier. This is nicely evinced by nicotinamide adenine dinucleotide phosphate (NADPH)-oxidases (NOX), enzymes whose primary function is to generate ROS and which have been shown to reside in specific lipid compartments. In addition, membrane-inserted bidirectional H2O2-transporters modulate their conductance precisely during the passage of the molecules through the lipid bilayer, ensuring time-scaled delivery of the signal. This review aims to summarize current evidence supporting the role of the plasma membrane as an organizing center that serves as a platform for redox signal transmission, particularly NOX-driven, providing specificity at the same time that limits undesirable oxidative damage in case of malfunction. As an example of malfunction, we explore several pathological situations in which an inflammatory component is present, such as inflammatory bowel disease and neurodegenerative disorders, to illustrate how dysregulation of plasma-membrane-localized redox signaling impacts normal cell physiology.
      Citation: Antioxidants
      PubDate: 2018-11-20
      DOI: 10.3390/antiox7110168
      Issue No: Vol. 7, No. 11 (2018)
       
  • Antioxidants, Vol. 7, Pages 169: Reactive Oxygen Species and the
           Redox-Regulatory Network in Cold Stress Acclimation

    • Authors: Anna Dreyer, Karl-Josef Dietz
      First page: 169
      Abstract: Cold temperatures restrict plant growth, geographical extension of plant species, and agricultural practices. This review deals with cold stress above freezing temperatures often defined as chilling stress. It focuses on the redox regulatory network of the cell under cold temperature conditions. Reactive oxygen species (ROS) function as the final electron sink in this network which consists of redox input elements, transmitters, targets, and sensors. Following an introduction to the critical network components which include nicotinamide adenine dinucleotide phosphate (NADPH)-dependent thioredoxin reductases, thioredoxins, and peroxiredoxins, typical laboratory experiments for cold stress investigations will be described. Short term transcriptome and metabolome analyses allow for dissecting the early responses of network components and complement the vast data sets dealing with changes in the antioxidant system and ROS. This review gives examples of how such information may be integrated to advance our knowledge on the response and function of the redox regulatory network in cold stress acclimation. It will be exemplarily shown that targeting the redox network might be beneficial and supportive to improve cold stress acclimation and plant yield in cold climate.
      Citation: Antioxidants
      PubDate: 2018-11-21
      DOI: 10.3390/antiox7110169
      Issue No: Vol. 7, No. 11 (2018)
       
  • Antioxidants, Vol. 7, Pages 124: Methionine Sulfoxide Reductases of
           Archaea

    • Authors: Julie A. Maupin-Furlow
      First page: 124
      Abstract: Methionine sulfoxide reductases are found in all domains of life and are important in reversing the oxidative damage of the free and protein forms of methionine, a sulfur containing amino acid particularly sensitive to reactive oxygen species (ROS). Archaea are microbes of a domain of life distinct from bacteria and eukaryotes. Archaea are well known for their ability to withstand harsh environmental conditions that range from habitats of high ROS, such as hypersaline lakes of intense ultraviolet (UV) radiation and desiccation, to hydrothermal vents of low concentrations of dissolved oxygen at high temperature. Recent evidence reveals the methionine sulfoxide reductases of archaea function not only in the reduction of methionine sulfoxide but also in the ubiquitin-like modification of protein targets during oxidative stress, an association that appears evolutionarily conserved in eukaryotes. Here is reviewed methionine sulfoxide reductases and their distribution and function in archaea.
      Citation: Antioxidants
      PubDate: 2018-09-20
      DOI: 10.3390/antiox7100124
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 125: Cell-Type-Specific Modulation of Hydrogen
           Peroxide Cytotoxicity and 4-Hydroxynonenal Binding to Human Cellular
           Proteins In Vitro by Antioxidant Aloe vera Extract

    • Authors: Vera Cesar, Iva Jozić, Lidija Begović, Tea Vuković, Selma Mlinarić, Hrvoje Lepeduš, Suzana Borović Šunjić, Neven Žarković
      First page: 125
      Abstract: Although Aloe vera contains numerous bioactive components, the activity principles of widely used A. vera extracts are uncertain. Therefore, we analyzed the effects of genuine A. vera aqueous extract (AV) on human cells with respect to the effects of hydrogen peroxide (H2O2) and 4-hydroxynonenal (HNE). Fully developed A. vera leaves were harvested and analyzed for vitamin C, carotenoids, total soluble phenolic content, and antioxidant capacity. Furthermore, human cervical cancer (HeLa), human microvascular endothelial cells (HMEC), human keratinocytes (HaCat), and human osteosarcoma (HOS) cell cultures were treated with AV extract for one hour after treatment with H2O2 or HNE. The cell number and viability were determined using Trypan Blue, and endogenous reactive oxygen species (ROS) production was determined by fluorescence, while intracellular HNE–protein adducts were measured for the first time ever by genuine cell-based HNE–His ELISA. The AV extract expressed strong antioxidant capacities (1.1 mmol of Trolox eq/g fresh weight) and cell-type-specific influence on the cytotoxicity of H2O2, as well as on endogenous production of ROS and HNE–protein adducts induced by HNE treatment, while AV itself did not induce production of ROS or HNE–protein adducts at all. This study, for the first time, revealed the importance of HNE for the activity principles of AV. Since HMEC cells were the most sensitive to AV, the effects of AV on microvascular endothelia could be of particular importance for the activity principles of Aloe vera extracts.
      Citation: Antioxidants
      PubDate: 2018-09-21
      DOI: 10.3390/antiox7100125
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 126: A Disturbance in the Force: Cellular
           Stress Sensing by the Mitochondrial Network

    • Authors: Robert Gilkerson
      First page: 126
      Abstract: As a highly dynamic organellar network, mitochondria are maintained as an organellar network by delicately balancing fission and fusion pathways. This homeostatic balance of organellar dynamics is increasingly revealed to play an integral role in sensing cellular stress stimuli. Mitochondrial fission/fusion balance is highly sensitive to perturbations such as loss of bioenergetic function, oxidative stress, and other stimuli, with mechanistic contribution to subsequent cell-wide cascades including inflammation, autophagy, and apoptosis. The overlapping activity with m-AAA protease 1 (OMA1) metallopeptidase, a stress-sensitive modulator of mitochondrial fusion, and dynamin-related protein 1 (DRP1), a regulator of mitochondrial fission, are key factors that shape mitochondrial dynamics in response to various stimuli. As such, OMA1 and DRP1 are critical factors that mediate mitochondrial roles in cellular stress-response signaling. Here, we explore the current understanding and emerging questions in the role of mitochondrial dynamics in sensing cellular stress as a dynamic, responsive organellar network.
      Citation: Antioxidants
      PubDate: 2018-09-22
      DOI: 10.3390/antiox7100126
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 127: Involvement of Neutrophil Dynamics and
           Function in Exercise-Induced Muscle Damage and Delayed-Onset Muscle
           Soreness: Effect of Hydrogen Bath

    • Authors: Takuji Kawamura, Katsuhiko Suzuki, Masaki Takahashi, Miki Tomari, Reira Hara, Yuko Gando, Isao Muraoka
      First page: 127
      Abstract: The purpose of this study was to investigate the involvement of neutrophil dynamics and function in exercise-induced muscle damage (EIMD) and delayed-onset muscle soreness (DOMS), and the effect of molecular hydrogen (H2) intake on these parameters. Nine healthy and active young men performed H2 and placebo bath trial in a crossover design. They carried out downhill running (−8% slope) for 30 min at a speed corresponding to 75~85% of peak oxygen uptake (VO2peak). Subsequently, they repeated bathing for 20 min per day for one week. Degree of muscle soreness (visual analogue scale: VAS), peripheral leukocyte counts, neutrophil dynamics and function, muscle damage, and inflammation markers were measured. Plasma interleukin (IL)-6 concentration was significantly correlated with peripheral neutrophil count, VAS, and serum creatine kinase activity, respectively, after downhill running. Peripheral neutrophil count and serum myoglobin concentration were also significantly correlated. Conversely, there were no effects of H2 bath. These results suggest that IL-6 may be involved in the mobilization of neutrophils into the peripheral blood and subsequent EIMD and DOMS after downhill running; however, it is not likely that H2 bath is effective for the inflammatory process that is centered on neutrophils after downhill running.
      Citation: Antioxidants
      PubDate: 2018-09-25
      DOI: 10.3390/antiox7100127
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 128: The Role of Methionine Sulfoxide
           Reductases in Oxidative Stress Tolerance and Virulence of Staphylococcus
           aureus and Other Bacteria

    • Authors: Vineet K. Singh, Kuldeep Singh, Kyle Baum
      First page: 128
      Abstract: Methionine sulfoxide reductases (MSRA1 and MSRB) are proteins overproduced in Staphylococcus aureus during exposure with cell wall-active antibiotics. Later studies identified the presence of two additional MSRA proteins (MSRA2 and MSRA3) in S. aureus. These MSR proteins have been characterized in many other bacteria as well. This review provides the current knowledge about the conditions and regulatory network that mimic the expression of these MSR encoding genes and their role in defense from oxidative stress and virulence.
      Citation: Antioxidants
      PubDate: 2018-09-28
      DOI: 10.3390/antiox7100128
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 129: Role of Hydrogen Sulfide in NRF2- and
           Sirtuin-Dependent Maintenance of Cellular Redox Balance

    • Authors: Tiziana Corsello, Narayana Komaravelli, Antonella Casola
      First page: 129
      Abstract: Hydrogen sulfide (H2S) has arisen as a critical gasotransmitter signaling molecule modulating cellular biological events related to health and diseases in heart, brain, liver, vascular systems and immune response. Three enzymes mediate the endogenous production of H2S: cystathione β-synthase (CBS), cystathione γ-lyase (CSE) and 3-mercaptopyruvate sulfurtransferase (3-MST). CBS and CSE localizations are organ-specific. 3-MST is a mitochondrial and cytosolic enzyme. The generation of H2S is firmly regulated by these enzymes under normal physiological conditions. Recent studies have highlighted the role of H2S in cellular redox homeostasis, as it displays significant antioxidant properties. H2S exerts antioxidant effects through several mechanisms, such as quenching reactive oxygen species (ROS) and reactive nitrogen species (RNS), by modulating cellular levels of glutathione (GSH) and thioredoxin (Trx-1) or increasing expression of antioxidant enzymes (AOE), by activating the transcription factor nuclear factor (erythroid-derived 2)-like 2 (NRF2). H2S also influences the activity of the histone deacetylase protein family of sirtuins, which plays an important role in inhibiting oxidative stress in cardiomyocytes and during the aging process by modulating AOE gene expression. This review focuses on the role of H2S in NRF2 and sirtuin signaling pathways as they are related to cellular redox homeostasis.
      Citation: Antioxidants
      PubDate: 2018-09-28
      DOI: 10.3390/antiox7100129
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 130: Redox Signaling of NADPH Oxidases
           Regulates Oxidative Stress Responses, Immunity and Aging

    • Authors: Collin Y. Ewald
      First page: 130
      Abstract: An accumulating body of evidence suggests that transient or physiological reactive oxygen species (ROS) generated by nicotinamide adenine dinucleotide phosphate (NADPH) oxidases act as a redox signal to re-establish homeostasis. The capacity to re-establish homeostasis progressively declines during aging but is maintained in long-lived animals to promote healthy aging. In the model organism Caenorhabditis elegans, ROS generated by dual oxidases (Duox) are important for extracellular matrix integrity, pathogen defense, oxidative stress resistance, and longevity. The Duox enzymatic activity is tightly regulated and under cellular control. Developmental molting cycles, pathogen infections, toxins, mitochondrial-derived ROS, drugs, and small GTPases (e.g., RHO-1) can activate Duox (BLI-3) to generate ROS, whereas NADPH oxidase inhibitors and negative regulators, such as MEMO-1, can inhibit Duox from generating ROS. Three mechanisms-of-action have been discovered for the Duox/BLI-3-generated ROS: (1) enzymatic activity to catalyze crosslinking of free tyrosine ethyl ester in collagen bundles to stabilize extracellular matrices, (2) high ROS bursts/levels to kill pathogens, and (3) redox signaling activating downstream kinase cascades to transcription factors orchestrating oxidative stress and immunity responses to re-establish homeostasis. Although Duox function at the cell surface is well established, recent genetic and biochemical data also suggests a novel role for Duoxs at the endoplasmic reticulum membrane to control redox signaling. Evidence underlying these mechanisms initiated by ROS from NADPH oxidases, and their relevance for human aging, are discussed in this review. Appropriately controlling NADPH oxidase activity for local and physiological redox signaling to maintain cellular homeostasis might be a therapeutic strategy to promote healthy aging.
      Citation: Antioxidants
      PubDate: 2018-09-28
      DOI: 10.3390/antiox7100130
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 131: Molecular Mechanisms of the Methionine
           Sulfoxide Reductase System from Neisseria meningitidis

    • Authors: Sandrine Boschi-Muller
      First page: 131
      Abstract: Neisseria meningitidis, an obligate pathogenic bacterium in humans, has acquired different defense mechanisms to detect and fight the oxidative stress generated by the host’s defense during infection. A notable example of such a mechanism is the PilB reducing system, which repairs oxidatively-damaged methionine residues. This review will focus on the catalytic mechanism of the two methionine sulfoxide reductase (MSR) domains of PilB, which represent model enzymes for catalysis of the reduction of a sulfoxide function by thiols through sulfenic acid chemistry. The mechanism of recycling of these MSR domains by various “Trx-like” disulfide oxidoreductases will also be discussed.
      Citation: Antioxidants
      PubDate: 2018-10-01
      DOI: 10.3390/antiox7100131
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 132: Oxidative Stress in the Male Germline: A
           Review of Novel Strategies to Reduce 4-Hydroxynonenal Production

    • Authors: Jessica L. H. Walters, Geoffry N. De Iuliis, Brett Nixon, Elizabeth G. Bromfield
      First page: 132
      Abstract: Germline oxidative stress is intimately linked to several reproductive pathologies including a failure of sperm-egg recognition. The lipid aldehyde 4-hydroxynonenal (4HNE) is particularly damaging to the process of sperm-egg recognition as it compromises the function and the stability of several germline proteins. Considering mature spermatozoa do not have the capacity for de novo protein translation, 4HNE modification of proteins in the mature gametes has uniquely severe consequences for protein homeostasis, cell function and cell survival. In somatic cells, 4HNE overproduction has been attributed to the action of lipoxygenase enzymes that facilitate the oxygenation and degradation of ω-6 polyunsaturated fatty acids (PUFAs). Accordingly, the arachidonate 15-lipoxygenase (ALOX15) enzyme has been intrinsically linked with 4HNE production, and resultant pathophysiology in various complex conditions such as coronary artery disease and multiple sclerosis. While ALOX15 has not been well characterized in germ cells, we postulate that ALOX15 inhibition may pose a new strategy to prevent 4HNE-induced protein modifications in the male germline. In this light, this review focuses on (i) 4HNE-induced protein damage in the male germline and its implications for fertility; and (ii) new methods for the prevention of lipid peroxidation in germ cells.
      Citation: Antioxidants
      PubDate: 2018-10-03
      DOI: 10.3390/antiox7100132
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 133: Effect of Natural Food Antioxidants
           against LDL and DNA Oxidative Changes

    • Authors: Sotirios Kiokias, Charalampos Proestos, Vassilki Oreopoulou
      First page: 133
      Abstract: Radical oxygen species formed in human tissue cells by many endogenous and exogenous pathways cause extensive oxidative damage which has been linked to various human diseases. This review paper provides an overview of lipid peroxidation and focuses on the free radicals-initiated processes of low-density lipoprotein (LDL) oxidative modification and DNA oxidative damage, which are widely associated with the initiation and development of atherosclerosis and carcinogenesis, respectively. The article subsequently provides an overview of the recent human trials or even in vitro investigations on the potential of natural antioxidant compounds (such as carotenoids; vitamins C and E) to monitor LDL and DNA oxidative changes.
      Citation: Antioxidants
      PubDate: 2018-10-03
      DOI: 10.3390/antiox7100133
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 134: Bioactive Compounds and Antioxidant
           Capacity of Rosa rugosa Depending on Degree of Ripeness

    • Authors: Ahlam Al-Yafeai, Peter Bellstedt, Volker Böhm
      First page: 134
      Abstract: Maturity stage affects the bioactive compounds as well as the antioxidant capacity in the fruit. This study was designed to identify and quantify carotenoids, as well as to evaluate vitamin E, vitamin C, antioxidant capacity and total phenolic compounds of Rosa rugosa hips at different degrees of ripeness. HPLC (high performance liquid chromatography) analysis showed different types of carotenoids at different stages of maturity of R. rugosa hips with significant differences (p ˂ 0.05), where the maximum concentration was observed at late harvesting. In the hips investigated, only α-tocopherol was detected, the maximum concentration of both vitamin E and vitamin C was obtained in the orange hips with significant difference (p ˂ 0.05). On the other hand, the highest hydrophilic and lipophilic TEAC (Trolox equivalent antioxidant capacity) values, as well as total phenolic contents, were determined in the mature hips (red colour) with significant difference (p < 0.0001) and (p < 0.001) respectively, whereas ORAC (oxygen radical absorbance capacity) showed lower activity in the mature hips with significant difference (p ˂ 0.05). Late harvesting is recommended if a high content of carotenoids is desired, while harvesting should be carried out earlier if a higher vitamin E and vitamin C content is desired, which in turn affects the antioxidants capacity.
      Citation: Antioxidants
      PubDate: 2018-10-03
      DOI: 10.3390/antiox7100134
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 135: Effects of Astaxanthin on the
           Proliferation and Migration of Breast Cancer Cells In Vitro

    • Authors: Buckley McCall, Connor K. McPartland, Reece Moore, Anastasia Frank-Kamenetskii, Brian W. Booth
      First page: 135
      Abstract: Astaxanthin (ASX) is a marine-based ketocarotenoid; an accessory pigment in plants in that it has many different potential functions. ASX is an antioxidant that is notably more potent than many other antioxidants. Antioxidants have anti-inflammatory and oxidative stress-reducing properties to potentially reduce the incidence of cancer or inhibit the expansion of tumor cells. In this study, we tested the hypothesis that ASX would inhibit proliferation and migration of breast cancer cells in vitro. We found that application of ASX significantly reduced proliferation rates and inhibited breast cancer cell migration compared to control normal breast epithelial cells. Based on these results, further investigation of the effects of ASX on not only breast cancer cells, but other forms of tumor cells, should be carried out.
      Citation: Antioxidants
      PubDate: 2018-10-04
      DOI: 10.3390/antiox7100135
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 136: Peroxiredoxins in Colorectal Cancer:
           Predictive Biomarkers of Radiation Response and Therapeutic Targets to
           Increase Radiation Sensitivity'

    • Authors: Jesse Fischer, Tim W. Eglinton, Frank A. Frizelle, Mark B. Hampton
      First page: 136
      Abstract: Colorectal cancer (CRC) is the third most common cancer in the Western world, with one-third of cases located in the rectum. Preoperative radiotherapy is the standard of care for many patients with rectal cancer but has a highly variable response rate. The ability to predict response would be of great clinical utility. The response of cells to ionizing radiation is known to involve immediate damage to biomolecules and more sustained disruption of redox homeostasis leading to cell death. The peroxiredoxins are an important group of thiol-dependent antioxidants involved in protecting cells from oxidative stress and regulating signaling pathways involved in cellular responses to oxidative stress. All six human peroxiredoxins have shown increased expression in CRC and may be associated with clinicopathological features and tumor response to ionizing radiation. Peroxiredoxins can act as markers of oxidative stress in various biological systems but they have not been investigated in this capacity in CRC. As such, there is currently insufficient evidence to support the role of peroxiredoxins as clinical biomarkers, but it is an area worthy of investigation. Future research should focus on the in vivo response of rectal cancer to radiotherapy and the redox status of peroxiredoxins in rectal cancer cells, in order to predict response to radiotherapy. The peroxiredoxin system is also a potential therapeutic target for CRC.
      Citation: Antioxidants
      PubDate: 2018-10-05
      DOI: 10.3390/antiox7100136
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 137: Antiradical and Xanthine Oxidase
           Inhibitory Activity Evaluations of Averrhoa bilimbi L. Leaves and
           Tentative Identification of Bioactive Constituents through LC-QTOF-MS/MS
           and Molecular Docking Approach

    • Authors: Qamar Uddin Ahmed, Alhassan Muhammad Alhassan, Alfi Khatib, Syed Adnan Ali Shah, Muhammad Mahmudul Hasan, Murni Nazira Sarian
      First page: 137
      Abstract: The objective of the present study was to investigate the antiradical and xanthine oxidase inhibitory effects of Averrhoa bilimbi leaves. Hence, crude methanolic leaves extract and its resultant fractions, namely hexane, chloroform, and n-butanol were evaluated for 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging effect and xanthine oxidase inhibitory activity. The active constituents were tentatively identified through LC-QTOF-MS/MS and molecular docking approaches. The n-butanol fraction of A. bilimbi crude methanolic leaves extract displayed significant DPPH radical scavenging effect with IC50 (4.14 ± 0.21 μg/mL) (p < 0.05), as well as xanthine oxidase inhibitory activity with IC50 (64.84 ± 3.93 μg/mL) (p < 0.05). Afzelechin 3-O-alpha-l-rhamnopyranoside and cucumerin A were tentatively identified as possible metabolites that contribute to the antioxidant activity of the n-butanol fraction.
      Citation: Antioxidants
      PubDate: 2018-10-08
      DOI: 10.3390/antiox7100137
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 138: Reduction of Real-Time Imaging of M1
           Macrophage Chemotaxis toward Damaged Muscle Cells is PI3K-Dependent

    • Authors: Hiromi Yano, Masataka Uchida, Tatsuya Saito, Takafumi Aoki, Michael J. Kremenik, Eri Oyanagi
      First page: 138
      Abstract: Macrophages migrate and invade into damaged muscle rapidly and are important for muscle repair and subsequent regeneration. The exact cellular and biological events that cause macrophage migration toward injured muscle are not completely understood. In this study, the effect of macrophage differentiation on the chemotactic capability to invade local damaged muscle was investigated using an in vitro model of muscle injury. We used C2C12 cell myoblasts and J774 cell macrophages, and the “killed-C2C12” cells were combined with live C2C12 cells as a partially damaged muscle model. The cultured J774 cells, with or without lipopolysaccharide (LPS), were treated with Ly294002 (Ly), which is an inhibitor of phosphoinositide 3-kinase (PI3K). In order to evaluate the polarization effect of LPS stimulation on J774 cells, expression of cell surface Toll-like receptor 4 (TLR4), CD11c and CCR2, and expression of F-actin intensity, were analyzed by flow cytometry. The real-time horizontal chemotaxis assay of J774 cells was tested using the TAXIScan device. The expressions of TLR4, CD11c, and F-actin intensity in LPS-treated cells were significantly higher than those in Ctrl cells. In LPS-treated cells, the chemotactic activity toward damaged muscle cells completely disappeared. Moreover, the reduced chemotaxis depended far more on directionality than velocity. However, Ly treatment reversed the reduced chemotactic activity of the LPS-treated cells. In addition, cell-adhesion and F-actin intensity, but not CCR2 expression, in LPS-treated cells, was significantly reduced by Ly treatment. Taken together, our results suggest that the PI3K/Akt activation state drives migration behavior towards damaged muscle cells.
      Citation: Antioxidants
      PubDate: 2018-10-08
      DOI: 10.3390/antiox7100138
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 139: On the Characterization and Correlation
           of Compositional, Antioxidant and Colour Profile of Common and Balsamic
           Vinegars

    • Authors: Vassilia J. Sinanoglou, Panagiotis Zoumpoulakis, Charalambos Fotakis, Nick Kalogeropoulos, Aikaterini Sakellari, Sotirios Karavoltsos, Irini F. Strati
      First page: 139
      Abstract: Commercially available common and balsamic vinegars were examined, using a combination of spectrophotometric, chromatographic, colorimetric and spectroscopic methods. Total phenolic content, antioxidant activity, radical scavenging capacity, phenolic profile, colour parameters, Fourier Transform Infrared (FT-IR) absorbance spectra and Nuclear Magnetic Resonance (1H NMR) spectra were comparatively studied. The main scope was the assessment of vinegar antioxidant and metabolic profiles and the identification of the most appropriate features influencing their type and subtypes. Red grape balsamic vinegars exhibited the strongest antioxidant profile. High total phenolic content and radical scavenging-antioxidant activity of vinegars was strongly correlated with high hue-angle and colour density values and low lightness and a* values. FT-IR spectra analysis confirmed the presence of organic acids and carbohydrates and, in combination with Gas Chromatography-Mass Spectrometry (GC-MS), the occurrence of phenolic compounds. NMR spectroscopy enabled the identification of 27 characteristic metabolites in each type of vinegar. The combination of all applied techniques provides critical information on compositional differences among the vinegars and could serve as an application tool for similar fermentation products.
      Citation: Antioxidants
      PubDate: 2018-10-11
      DOI: 10.3390/antiox7100139
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 140: Oxidation of Methionine 77 in Calmodulin
           Alters Mouse Growth and Behavior

    • Authors: Méry Marimoutou, Danielle Springer, Chengyu Liu, Geumsoo Kim, Rodney Levine
      First page: 140
      Abstract: Methionine 77 in calmodulin can be stereospecifically oxidized to methionine sulfoxide by mammalian methionine sulfoxide reductase A. Whether this has in vivo significance is unknown. We therefore created a mutant mouse in which wild type calmodulin-1 was replaced by a calmodulin containing a mimic of methionine sulfoxide at residue 77. Total calmodulin levels were unchanged in the homozygous M77Q mutant, which is viable and fertile. No differences were observed on learning tests, including the Morris water maze and associative learning. Cardiac stress test results were also the same for mutant and wild type mice. However, young male and female mice were 20% smaller than wild type mice, although food intake was normal for their weight. Young M77Q mice were notably more active and exploratory than wild type mice. This behavior difference was objectively documented on the treadmill and open field tests. The mutant mice ran 20% longer on the treadmill than controls and in the open field test, the mutant mice explored more than controls and exhibited reduced anxiety. These phenotypic differences bore a similarity to those observed in mice lacking calcium/calmodulin kinase IIα (CaMKIIα). We then showed that MetO77 calmodulin was less effective in activating CaMKIIα than wild type calmodulin. Thus, characterization of the phenotype of a mouse expressing a constitutively active mimic of calmodulin led to the identification of the first calmodulin target that can be differentially regulated by the oxidation state of Met77. We conclude that reversible oxidation of methionine 77 in calmodulin by MSRA has the potential to regulate cellular function.
      Citation: Antioxidants
      PubDate: 2018-10-13
      DOI: 10.3390/antiox7100140
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 141: CoQ10 Supplementation in Patients
           Undergoing IVF-ET: The Relationship with Follicular Fluid Content and
           Oocyte Maturity

    • Authors: Stefano Giannubilo, Patrick Orlando, Sonia Silvestri, Ilenia Cirilli, Fabio Marcheggiani, Andrea Ciavattini, Luca Tiano
      First page: 141
      Abstract: Background: The target of the reduced fecundity with aging is the oocyte. The follicular fluid and its components are strongly linked with the environment of the maturing oocyte. The aim of the present study was to evaluate CoQ10 bioavailability in follicular fluids after oral supplementation and its possible implication in oocyte maturation. Methods: Fifteen female partners of infertile couples, aged 31–46, undergoing IVF-ET and taking 200 mg/day oral CoQ10 were compared to unsupplemented patients. CoQ10 content, its oxidative status and total antioxidant capacity were evaluated also in relation to oocyte maturation indexes. Results: CoQ10 supplementation produced a significant increase in follicular content and a significant improvement of its oxidative status. Follicular fluid total antioxidant capacity highlighted a significant decrease in patients supplemented with CoQ10, specially in women >35 years. CoQ10 supplementation was associated with a significant decrease in total antioxidant capacity of fluid from follicles containing mature oocyte, moreover CoQ10 oxidative status was also significantly reduced but in follicles containing immature oocyte. Conclusions: Our observation leads to the hypothesis that the oral supplementation of CoQ10 may improve follicular fluid oxidative metabolism and oocyte quality, specially in over 35-year-old women.
      Citation: Antioxidants
      PubDate: 2018-10-13
      DOI: 10.3390/antiox7100141
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 142: Mitochondrial Arabidopsis thaliana TRXo
           Isoforms Bind an Iron–Sulfur Cluster and Reduce NFU Proteins In Vitro

    • Authors: Flavien Zannini, Thomas Roret, Jonathan Przybyla-Toscano, Tiphaine Dhalleine, Nicolas Rouhier, Jérémy Couturier
      First page: 142
      Abstract: In plants, the mitochondrial thioredoxin (TRX) system generally comprises only one or two isoforms belonging to the TRX h or o classes, being less well developed compared to the numerous isoforms found in chloroplasts. Unlike most other plant species, Arabidopsis thaliana possesses two TRXo isoforms whose physiological functions remain unclear. Here, we performed a structure–function analysis to unravel the respective properties of the duplicated TRXo1 and TRXo2 isoforms. Surprisingly, when expressed in Escherichia coli, both recombinant proteins existed in an apo-monomeric form and in a homodimeric iron–sulfur (Fe-S) cluster-bridged form. In TRXo2, the [4Fe-4S] cluster is likely ligated in by the usual catalytic cysteines present in the conserved Trp-Cys-Gly-Pro-Cys signature. Solving the three-dimensional structure of both TRXo apo-forms pointed to marked differences in the surface charge distribution, notably in some area usually participating to protein–protein interactions with partners. However, we could not detect a difference in their capacity to reduce nitrogen-fixation-subunit-U (NFU)-like proteins, NFU4 or NFU5, two proteins participating in the maturation of certain mitochondrial Fe-S proteins and previously isolated as putative TRXo1 partners. Altogether, these results suggest that a novel regulation mechanism may prevail for mitochondrial TRXs o, possibly existing as a redox-inactive Fe-S cluster-bound form that could be rapidly converted in a redox-active form upon cluster degradation in specific physiological conditions.
      Citation: Antioxidants
      PubDate: 2018-10-13
      DOI: 10.3390/antiox7100142
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 143: Determination of Three Main Chlorogenic
           Acids in Water Extracts of Coffee Leaves by Liquid Chromatography Coupled
           to an Electrochemical Detector

    • Authors: Rocío Rodríguez-Gómez, Jérôme Vanheuverzwjin, Florence Souard, Cédric Delporte, Caroline Stevigny, Piet Stoffelen, Kris De Braekeleer, Jean-Michel Kauffmann
      First page: 143
      Abstract: Coffee is a beverage widely consumed in the world. The coffee species most commercialized worldwide are Arabica (Coffea arabica) and Robusta (Coffea canephora). Roasted coffee beans are the most used, but coffee leaves are also consumed as infusion in several countries for traditional medicinal purposes. They contain several interesting phenolic antioxidant compounds mainly belonging to chlorogenic acids (CGAs). In the present work, a liquid chromatography-electrochemical detection (LC-EC) method was developed for the determination of three main chlorogenic acid isomers, namely 3-, 4-, and 5-caffeoylquinic acids (CQA), in coffee leaves aqueous extracts. Samples from eight coffee species, namely; Coffea arabica, Coffea canephora, Coffea liberica, Coffea humilis, Coffea mannii, Coffea charrieriana, Coffea anthonyi, and Coffea liberica var. liberica, were grown and collected in tropical greenhouses. Linearity of the calibration graphs was observed in the range from the limit of quantification to 1.0 × 10−5 M, with R2 equal to 99.9% in all cases. High sensitivity was achieved with a limit of detection of 1.0 × 10−8 M for 3-CQA and 5-CQA (i.e., 3.5 µg/L) and 2.0 × 10−8 M for 4-CQA (i.e., 7.1 µg/L). The chromatographic profile of the samples harvested for each Coffea species was studied comparatively. Obtained raw data were pretreated for baseline variations and shifts in retention times between the chromatographic profiles. Principal Component Analysis (PCA) was applied to the pretreated data. According to the results, three clusters of Coffea species were found. In the water sample extracts, 5-CQA appeared to be the major isomer, and some species contained a very low amount of CQAs. Fluctuations were observed depending on the Coffea species and harvesting period. Significant differences between January and July were noticed regarding CQAs content. The species with the best CQAs/caffeine ratio was identified. The LC-EC data were validated by liquid chromatography-high resolution mass spectrometry (LC-HRMS).
      Citation: Antioxidants
      PubDate: 2018-10-15
      DOI: 10.3390/antiox7100143
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 144: Effects of a Two-Year Home-Based Exercise
           Training Program on Oxidized LDL and HDL Lipids in Coronary Artery Disease
           Patients with and without Type-2 Diabetes

    • Authors: Sanna Tiainen, Antti Kiviniemi, Arto Hautala, Heikki Huikuri, Olavi Ukkola, Kari Tokola, Mikko Tulppo, Tommi Vasankari
      First page: 144
      Abstract: We investigated the effect of two-year home-based exercise training program on oxidized low-density lipoprotein LDL (ox-LDL) and high-density lipoprotein HDL (ox-HDL) lipids in patients with coronary artery disease (CAD), both with and without type-2 diabetes (T2D). Analysis of lipoprotein-oxidized lipids was based on the determination of baseline conjugated dienes in lipoprotein lipids. In order to study the effect of an exercise load on ox-LDL and ox-HDL lipids patients in both CAD and CAD + T2D intervention, groups were divided in three based on exercise load (high, medium, and low). During the two-year home-based exercise training program, the study showed that only higher training volume resulted in a decreased concentration of ox-LDL, while the two groups with lower training volumes showed no change. This result indicates that the training load needs to be sufficiently high in order to decrease the concentration of atherogenic ox-LDL lipids in patients with CAD and CAD + T2D. Interestingly, the concentration of ox-HDL did not change in any of the subgroups. This could indicate that the lipid peroxide-transporting capacity of HDL, suggested by results from exercise training studies in healthy adults, may not function similarly in CAD patients with or without T2D. Moreover, the lipid-lowering medication used may have had an influence on these results.
      Citation: Antioxidants
      PubDate: 2018-10-16
      DOI: 10.3390/antiox7100144
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 145: Oxidative Stress and Arterial Dysfunction
           in Peripheral Artery Disease

    • Authors: Ahmed Ismaeel, Robert S. Brumberg, Jeffrey S. Kirk, Evlampia Papoutsi, Patrick J. Farmer, William T. Bohannon, Robert S. Smith, Jack L. Eidson, Ian Sawicki, Panagiotis Koutakis
      First page: 145
      Abstract: Peripheral artery disease (PAD) is an atherosclerotic disease characterized by a narrowing of the arteries in the lower extremities. Disease manifestations are the result of more than just reduced blood flow, and include endothelial dysfunction, arterial stiffness, and inflammation. Growing evidence suggests that these factors lead to functional impairment and decline in PAD patients. Oxidative stress also plays an important role in the disease, and a growing amount of data suggest a link between arterial dysfunction and oxidative stress. In this review, we present the current evidence for the involvement of endothelial dysfunction, arterial stiffness, and inflammation in the pathophysiology of PAD. We also discuss the links between these factors and oxidative stress, with a focus on nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (NOX2)-derived reactive oxygen species (ROS) and decreased nitric oxide (NO) bioavailability. Finally, the potential therapeutic role of NOX2 antioxidants for improving arterial function and functional status in PAD patients is explored.
      Citation: Antioxidants
      PubDate: 2018-10-19
      DOI: 10.3390/antiox7100145
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 146: Redox for Repair: Cold Physical Plasmas
           and Nrf2 Signaling Promoting Wound Healing

    • Authors: Anke Schmidt, Sander Bekeschus
      First page: 146
      Abstract: Chronic wounds and ulcers are major public health threats. Being a substantial burden for patients and health care systems alike, better understanding of wound pathophysiology and new avenues in the therapy of chronic wounds are urgently needed. Cold physical plasmas are particularly effective in promoting wound closure, irrespective of its etiology. These partially ionized gases deliver a therapeutic cocktail of reactive oxygen and nitrogen species safely at body temperature and without genotoxic side effects. This field of plasma medicine reanimates the idea of redox repair in physiological healing. This review compiles previous findings of plasma effects in wound healing. It discusses new links between plasma treatment of cells and tissues, and the perception and intracellular translation of plasma-derived reactive species via redox signaling pathways. Specifically, (i) molecular switches governing redox-mediated tissue response; (ii) the activation of the nuclear E2-related factor (Nrf2) signaling, together with antioxidative and immunomodulatory responses; and (iii) the stabilization of the scaffolding function and actin network in dermal fibroblasts are emphasized in the light of wound healing.
      Citation: Antioxidants
      PubDate: 2018-10-19
      DOI: 10.3390/antiox7100146
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 147: Cytoprotective Effects of Natural
           Compounds against Oxidative Stress

    • Authors: Jay Mehta, Srujana Rayalam, Xinyu Wang
      First page: 147
      Abstract: Oxidative stress, an imbalance between reactive oxygen species and antioxidants, has been witnessed in pathophysiological states of many disorders. Compounds identified from natural sources have long been recognized to ameliorate oxidative stress due to their inherent antioxidant activities. Here, we summarize the cytoprotective effects and mechanisms of natural or naturally derived synthetic compounds against oxidative stress. These compounds include: caffeic acid phenethyl ester (CAPE) found in honey bee propolis, curcumin from turmeric roots, resveratrol abundant in grape, and 1-[2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oyl] imidazole (CDDO-Im), a synthetic triterpenoid based on naturally occurring oleanolic acid. Cytoprotective effects of these compounds in diseases conditions like cardiovascular diseases and obesity to decrease oxidative stress are discussed.
      Citation: Antioxidants
      PubDate: 2018-10-20
      DOI: 10.3390/antiox7100147
      Issue No: Vol. 7, No. 10 (2018)
       
  • Antioxidants, Vol. 7, Pages 148: A Review of the Effects of Leucine
           Metabolite (β-Hydroxy-β-methylbutyrate) Supplementation and Resistance
           Training on Inflammatory Markers: A New Approach to Oxidative Stress and
           Cardiovascular Risk Factors

    • Authors: Hamid Arazi, Behzad Taati, Katsuhiko Suzuki
      First page: 148
      Abstract: β-hydroxy β-methylbutyrate (HMB) is a bioactive metabolite formed from the breakdown of the branched-chain amino acid, leucine. Given the popularity of HMB supplements among different athletes, specifically, those who participate in regular resistance training, this review was performed to summarize current literature on some aspects of HMB supplementation that have received less attention. Because of the small number of published studies, it has not been possible to conclude the exact effects of HMB on cardiovascular parameters, oxidative stress, and inflammatory markers. Thus, the interpretation of outcomes should be taken cautiously. However, the data presented here suggest that acute HMB supplementation may attenuate the pro-inflammatory response following an intense bout of resistance exercise in athletes. Also, the available findings collectively indicate that chronic HMB consumption with resistance training does not improve cardiovascular risk factors and oxidative stress markers greater than resistance training alone. Taken together, there is clearly a need for further well-designed, long-term studies to support these findings and determine whether HMB supplementation affects the adaptations induced by resistance training associated with the body’s inflammatory condition, antioxidative defense system, and cardiovascular risk factors in humans.
      Citation: Antioxidants
      PubDate: 2018-10-20
      DOI: 10.3390/antiox7100148
      Issue No: Vol. 7, No. 10 (2018)
       
 
 
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