for Journals by Title or ISSN
for Articles by Keywords
help

Publisher: John Wiley and Sons   (Total: 1592 journals)

 A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z  

        1 2 3 4 5 6 7 8 | Last   [Sort by number of followers]   [Restore default list]

Showing 1 - 200 of 1592 Journals sorted alphabetically
Abacus     Hybrid Journal   (Followers: 13, SJR: 0.48, h-index: 22)
About Campus     Hybrid Journal   (Followers: 5)
Academic Emergency Medicine     Hybrid Journal   (Followers: 66, SJR: 1.385, h-index: 91)
Accounting & Finance     Hybrid Journal   (Followers: 47, SJR: 0.547, h-index: 30)
ACEP NOW     Free   (Followers: 1)
Acta Anaesthesiologica Scandinavica     Hybrid Journal   (Followers: 54, SJR: 1.02, h-index: 88)
Acta Archaeologica     Hybrid Journal   (Followers: 171, SJR: 0.101, h-index: 9)
Acta Geologica Sinica (English Edition)     Hybrid Journal   (Followers: 3, SJR: 0.552, h-index: 41)
Acta Neurologica Scandinavica     Hybrid Journal   (Followers: 5, SJR: 1.203, h-index: 74)
Acta Obstetricia et Gynecologica Scandinavica     Hybrid Journal   (Followers: 14, SJR: 1.197, h-index: 81)
Acta Ophthalmologica     Hybrid Journal   (Followers: 6, SJR: 0.112, h-index: 1)
Acta Paediatrica     Hybrid Journal   (Followers: 56, SJR: 0.794, h-index: 88)
Acta Physiologica     Hybrid Journal   (Followers: 6, SJR: 1.69, h-index: 88)
Acta Polymerica     Hybrid Journal   (Followers: 9)
Acta Psychiatrica Scandinavica     Hybrid Journal   (Followers: 37, SJR: 2.518, h-index: 113)
Acta Zoologica     Hybrid Journal   (Followers: 7, SJR: 0.459, h-index: 29)
Acute Medicine & Surgery     Hybrid Journal   (Followers: 5)
Addiction     Hybrid Journal   (Followers: 36, SJR: 2.086, h-index: 143)
Addiction Biology     Hybrid Journal   (Followers: 15, SJR: 2.091, h-index: 57)
Adultspan J.     Hybrid Journal   (SJR: 0.127, h-index: 4)
Advanced Energy Materials     Hybrid Journal   (Followers: 26, SJR: 6.411, h-index: 86)
Advanced Engineering Materials     Hybrid Journal   (Followers: 26, SJR: 0.81, h-index: 81)
Advanced Functional Materials     Hybrid Journal   (Followers: 51, SJR: 5.21, h-index: 203)
Advanced Healthcare Materials     Hybrid Journal   (Followers: 14, SJR: 0.232, h-index: 7)
Advanced Materials     Hybrid Journal   (Followers: 279, SJR: 9.021, h-index: 345)
Advanced Materials Interfaces     Hybrid Journal   (Followers: 6, SJR: 1.177, h-index: 10)
Advanced Optical Materials     Hybrid Journal   (Followers: 7, SJR: 2.488, h-index: 21)
Advanced Science     Open Access   (Followers: 5)
Advanced Synthesis & Catalysis     Hybrid Journal   (Followers: 18, SJR: 2.729, h-index: 121)
Advances in Polymer Technology     Hybrid Journal   (Followers: 13, SJR: 0.344, h-index: 31)
Africa Confidential     Hybrid Journal   (Followers: 21)
Africa Research Bulletin: Economic, Financial and Technical Series     Hybrid Journal   (Followers: 13)
Africa Research Bulletin: Political, Social and Cultural Series     Hybrid Journal   (Followers: 11)
African Development Review     Hybrid Journal   (Followers: 33, SJR: 0.275, h-index: 17)
African J. of Ecology     Hybrid Journal   (Followers: 16, SJR: 0.477, h-index: 39)
Aggressive Behavior     Hybrid Journal   (Followers: 16, SJR: 1.391, h-index: 66)
Aging Cell     Open Access   (Followers: 11, SJR: 4.374, h-index: 95)
Agribusiness : an Intl. J.     Hybrid Journal   (Followers: 3, SJR: 0.627, h-index: 14)
Agricultural and Forest Entomology     Hybrid Journal   (Followers: 16, SJR: 0.925, h-index: 43)
Agricultural Economics     Hybrid Journal   (Followers: 45, SJR: 1.099, h-index: 51)
AIChE J.     Hybrid Journal   (Followers: 32, SJR: 1.122, h-index: 120)
Alcoholism and Drug Abuse Weekly     Hybrid Journal   (Followers: 7)
Alcoholism Clinical and Experimental Research     Hybrid Journal   (Followers: 7, SJR: 1.416, h-index: 125)
Alimentary Pharmacology & Therapeutics     Hybrid Journal   (Followers: 34, SJR: 2.833, h-index: 138)
Alimentary Pharmacology & Therapeutics Symposium Series     Hybrid Journal   (Followers: 3)
Allergy     Hybrid Journal   (Followers: 51, SJR: 3.048, h-index: 129)
Alternatives to the High Cost of Litigation     Hybrid Journal   (Followers: 3)
American Anthropologist     Hybrid Journal   (Followers: 152, SJR: 0.951, h-index: 61)
American Business Law J.     Hybrid Journal   (Followers: 24, SJR: 0.205, h-index: 17)
American Ethnologist     Hybrid Journal   (Followers: 93, SJR: 2.325, h-index: 51)
American J. of Economics and Sociology     Hybrid Journal   (Followers: 29, SJR: 0.211, h-index: 26)
American J. of Hematology     Hybrid Journal   (Followers: 35, SJR: 1.761, h-index: 77)
American J. of Human Biology     Hybrid Journal   (Followers: 13, SJR: 1.018, h-index: 58)
American J. of Industrial Medicine     Hybrid Journal   (Followers: 16, SJR: 0.993, h-index: 85)
American J. of Medical Genetics Part A     Hybrid Journal   (Followers: 17, SJR: 1.115, h-index: 61)
American J. of Medical Genetics Part B: Neuropsychiatric Genetics     Hybrid Journal   (Followers: 4, SJR: 1.771, h-index: 107)
American J. of Medical Genetics Part C: Seminars in Medical Genetics     Partially Free   (Followers: 6, SJR: 2.315, h-index: 79)
American J. of Physical Anthropology     Hybrid Journal   (Followers: 38, SJR: 1.41, h-index: 88)
American J. of Political Science     Hybrid Journal   (Followers: 296, SJR: 5.101, h-index: 114)
American J. of Primatology     Hybrid Journal   (Followers: 15, SJR: 1.197, h-index: 63)
American J. of Reproductive Immunology     Hybrid Journal   (Followers: 4, SJR: 1.347, h-index: 75)
American J. of Transplantation     Hybrid Journal   (Followers: 18, SJR: 2.792, h-index: 140)
American J. on Addictions     Hybrid Journal   (Followers: 10, SJR: 0.843, h-index: 57)
Anaesthesia     Hybrid Journal   (Followers: 141, SJR: 1.404, h-index: 88)
Analyses of Social Issues and Public Policy     Hybrid Journal   (Followers: 10, SJR: 0.397, h-index: 18)
Analytic Philosophy     Hybrid Journal   (Followers: 20)
Anatomia, Histologia, Embryologia: J. of Veterinary Medicine Series C     Hybrid Journal   (Followers: 3, SJR: 0.295, h-index: 27)
Anatomical Sciences Education     Hybrid Journal   (Followers: 1, SJR: 0.633, h-index: 24)
Andrologia     Hybrid Journal   (Followers: 2, SJR: 0.528, h-index: 45)
Andrology     Hybrid Journal   (Followers: 2, SJR: 0.979, h-index: 14)
Angewandte Chemie     Hybrid Journal   (Followers: 166)
Angewandte Chemie Intl. Edition     Hybrid Journal   (Followers: 234, SJR: 6.229, h-index: 397)
Animal Conservation     Hybrid Journal   (Followers: 41, SJR: 1.576, h-index: 62)
Animal Genetics     Hybrid Journal   (Followers: 8, SJR: 0.957, h-index: 67)
Animal Science J.     Hybrid Journal   (Followers: 6, SJR: 0.569, h-index: 24)
Annalen der Physik     Hybrid Journal   (Followers: 5, SJR: 1.46, h-index: 40)
Annals of Anthropological Practice     Partially Free   (Followers: 2, SJR: 0.187, h-index: 5)
Annals of Applied Biology     Hybrid Journal   (Followers: 7, SJR: 0.816, h-index: 56)
Annals of Clinical and Translational Neurology     Open Access   (Followers: 1)
Annals of Human Genetics     Hybrid Journal   (Followers: 9, SJR: 1.191, h-index: 67)
Annals of Neurology     Hybrid Journal   (Followers: 49, SJR: 5.584, h-index: 241)
Annals of Noninvasive Electrocardiology     Hybrid Journal   (Followers: 1, SJR: 0.531, h-index: 38)
Annals of Public and Cooperative Economics     Hybrid Journal   (Followers: 8, SJR: 0.336, h-index: 23)
Annals of the New York Academy of Sciences     Hybrid Journal   (Followers: 5, SJR: 2.389, h-index: 189)
Annual Bulletin of Historical Literature     Hybrid Journal   (Followers: 12)
Annual Review of Information Science and Technology     Hybrid Journal   (Followers: 14)
Anthropology & Education Quarterly     Hybrid Journal   (Followers: 26, SJR: 0.72, h-index: 31)
Anthropology & Humanism     Hybrid Journal   (Followers: 18, SJR: 0.137, h-index: 3)
Anthropology News     Hybrid Journal   (Followers: 15)
Anthropology of Consciousness     Hybrid Journal   (Followers: 11, SJR: 0.172, h-index: 5)
Anthropology of Work Review     Hybrid Journal   (Followers: 11, SJR: 0.256, h-index: 5)
Anthropology Today     Hybrid Journal   (Followers: 93, SJR: 0.545, h-index: 15)
Antipode     Hybrid Journal   (Followers: 52, SJR: 2.212, h-index: 69)
Anz J. of Surgery     Hybrid Journal   (Followers: 8, SJR: 0.432, h-index: 59)
Anzeiger für Schädlingskunde     Hybrid Journal   (Followers: 1)
Apmis     Hybrid Journal   (Followers: 1, SJR: 0.855, h-index: 73)
Applied Cognitive Psychology     Hybrid Journal   (Followers: 73, SJR: 0.754, h-index: 69)
Applied Organometallic Chemistry     Hybrid Journal   (Followers: 7, SJR: 0.632, h-index: 58)
Applied Psychology     Hybrid Journal   (Followers: 181, SJR: 1.023, h-index: 64)
Applied Psychology: Health and Well-Being     Hybrid Journal   (Followers: 51, SJR: 0.868, h-index: 13)
Applied Stochastic Models in Business and Industry     Hybrid Journal   (Followers: 5, SJR: 0.613, h-index: 24)
Aquaculture Nutrition     Hybrid Journal   (Followers: 14, SJR: 1.025, h-index: 55)
Aquaculture Research     Hybrid Journal   (Followers: 32, SJR: 0.807, h-index: 60)
Aquatic Conservation Marine and Freshwater Ecosystems     Hybrid Journal   (Followers: 36, SJR: 1.047, h-index: 57)
Arabian Archaeology and Epigraphy     Hybrid Journal   (Followers: 11, SJR: 0.453, h-index: 11)
Archaeological Prospection     Hybrid Journal   (Followers: 12, SJR: 0.922, h-index: 21)
Archaeology in Oceania     Hybrid Journal   (Followers: 13, SJR: 0.745, h-index: 18)
Archaeometry     Hybrid Journal   (Followers: 30, SJR: 0.809, h-index: 48)
Archeological Papers of The American Anthropological Association     Hybrid Journal   (Followers: 15, SJR: 0.156, h-index: 2)
Architectural Design     Hybrid Journal   (Followers: 27, SJR: 0.261, h-index: 9)
Archiv der Pharmazie     Hybrid Journal   (Followers: 3, SJR: 0.628, h-index: 43)
Archives of Drug Information     Hybrid Journal   (Followers: 5)
Archives of Insect Biochemistry and Physiology     Hybrid Journal   (SJR: 0.768, h-index: 54)
Area     Hybrid Journal   (Followers: 13, SJR: 0.938, h-index: 57)
Art History     Hybrid Journal   (Followers: 267, SJR: 0.153, h-index: 13)
Arthritis & Rheumatology     Hybrid Journal   (Followers: 55, SJR: 1.984, h-index: 20)
Arthritis Care & Research     Hybrid Journal   (Followers: 27, SJR: 2.256, h-index: 114)
Artificial Organs     Hybrid Journal   (Followers: 1, SJR: 0.872, h-index: 60)
ASHE Higher Education Reports     Hybrid Journal   (Followers: 15)
Asia & the Pacific Policy Studies     Open Access   (Followers: 16)
Asia Pacific J. of Human Resources     Hybrid Journal   (Followers: 326, SJR: 0.494, h-index: 19)
Asia Pacific Viewpoint     Hybrid Journal   (Followers: 1, SJR: 0.616, h-index: 26)
Asia-Pacific J. of Chemical Engineering     Hybrid Journal   (Followers: 8, SJR: 0.345, h-index: 20)
Asia-pacific J. of Clinical Oncology     Hybrid Journal   (Followers: 6, SJR: 0.554, h-index: 14)
Asia-Pacific J. of Financial Studies     Hybrid Journal   (SJR: 0.241, h-index: 7)
Asia-Pacific Psychiatry     Hybrid Journal   (Followers: 4, SJR: 0.377, h-index: 7)
Asian Economic J.     Hybrid Journal   (Followers: 8, SJR: 0.234, h-index: 21)
Asian Economic Policy Review     Hybrid Journal   (Followers: 4, SJR: 0.196, h-index: 12)
Asian J. of Control     Hybrid Journal   (SJR: 0.862, h-index: 34)
Asian J. of Endoscopic Surgery     Hybrid Journal   (Followers: 1, SJR: 0.394, h-index: 7)
Asian J. of Organic Chemistry     Hybrid Journal   (Followers: 6, SJR: 1.443, h-index: 19)
Asian J. of Social Psychology     Hybrid Journal   (Followers: 5, SJR: 0.665, h-index: 37)
Asian Politics and Policy     Hybrid Journal   (Followers: 12, SJR: 0.207, h-index: 7)
Asian Social Work and Policy Review     Hybrid Journal   (Followers: 5, SJR: 0.318, h-index: 5)
Asian-pacific Economic Literature     Hybrid Journal   (Followers: 5, SJR: 0.168, h-index: 15)
Assessment Update     Hybrid Journal   (Followers: 4)
Astronomische Nachrichten     Hybrid Journal   (Followers: 3, SJR: 0.701, h-index: 40)
Atmospheric Science Letters     Open Access   (Followers: 29, SJR: 1.332, h-index: 27)
Austral Ecology     Hybrid Journal   (Followers: 15, SJR: 1.095, h-index: 66)
Austral Entomology     Hybrid Journal   (Followers: 9, SJR: 0.524, h-index: 28)
Australasian J. of Dermatology     Hybrid Journal   (Followers: 8, SJR: 0.714, h-index: 40)
Australasian J. On Ageing     Hybrid Journal   (Followers: 6, SJR: 0.39, h-index: 22)
Australian & New Zealand J. of Statistics     Hybrid Journal   (Followers: 14, SJR: 0.275, h-index: 28)
Australian Accounting Review     Hybrid Journal   (Followers: 3, SJR: 0.709, h-index: 14)
Australian and New Zealand J. of Family Therapy (ANZJFT)     Hybrid Journal   (Followers: 3, SJR: 0.382, h-index: 12)
Australian and New Zealand J. of Obstetrics and Gynaecology     Hybrid Journal   (Followers: 47, SJR: 0.814, h-index: 49)
Australian and New Zealand J. of Public Health     Hybrid Journal   (Followers: 13, SJR: 0.82, h-index: 62)
Australian Dental J.     Hybrid Journal   (Followers: 6, SJR: 0.482, h-index: 46)
Australian Economic History Review     Hybrid Journal   (Followers: 6, SJR: 0.171, h-index: 12)
Australian Economic Papers     Hybrid Journal   (Followers: 31, SJR: 0.23, h-index: 9)
Australian Economic Review     Hybrid Journal   (Followers: 6, SJR: 0.357, h-index: 21)
Australian Endodontic J.     Hybrid Journal   (Followers: 3, SJR: 0.513, h-index: 24)
Australian J. of Agricultural and Resource Economics     Hybrid Journal   (Followers: 3, SJR: 0.765, h-index: 36)
Australian J. of Grape and Wine Research     Hybrid Journal   (Followers: 5, SJR: 0.879, h-index: 56)
Australian J. of Politics & History     Hybrid Journal   (Followers: 15, SJR: 0.203, h-index: 14)
Australian J. of Psychology     Hybrid Journal   (Followers: 18, SJR: 0.384, h-index: 30)
Australian J. of Public Administration     Hybrid Journal   (Followers: 429, SJR: 0.418, h-index: 29)
Australian J. of Rural Health     Hybrid Journal   (Followers: 6, SJR: 0.43, h-index: 34)
Australian Occupational Therapy J.     Hybrid Journal   (Followers: 74, SJR: 0.59, h-index: 29)
Australian Psychologist     Hybrid Journal   (Followers: 12, SJR: 0.331, h-index: 31)
Australian Veterinary J.     Hybrid Journal   (Followers: 23, SJR: 0.459, h-index: 45)
Autism Research     Hybrid Journal   (Followers: 37, SJR: 2.126, h-index: 39)
Autonomic & Autacoid Pharmacology     Hybrid Journal   (SJR: 0.371, h-index: 29)
Banks in Insurance Report     Hybrid Journal   (Followers: 1)
Basic & Clinical Pharmacology & Toxicology     Hybrid Journal   (Followers: 11, SJR: 0.539, h-index: 70)
Basic and Applied Pathology     Open Access   (Followers: 2, SJR: 0.113, h-index: 4)
Basin Research     Hybrid Journal   (Followers: 5, SJR: 1.54, h-index: 60)
Bauphysik     Hybrid Journal   (Followers: 2, SJR: 0.194, h-index: 5)
Bauregelliste A, Bauregelliste B Und Liste C     Hybrid Journal  
Bautechnik     Hybrid Journal   (Followers: 1, SJR: 0.321, h-index: 11)
Behavioral Interventions     Hybrid Journal   (Followers: 9, SJR: 0.297, h-index: 23)
Behavioral Sciences & the Law     Hybrid Journal   (Followers: 23, SJR: 0.736, h-index: 57)
Berichte Zur Wissenschaftsgeschichte     Hybrid Journal   (Followers: 10, SJR: 0.11, h-index: 5)
Beton- und Stahlbetonbau     Hybrid Journal   (Followers: 2, SJR: 0.493, h-index: 14)
Biochemistry and Molecular Biology Education     Hybrid Journal   (Followers: 6, SJR: 0.311, h-index: 26)
Bioelectromagnetics     Hybrid Journal   (Followers: 1, SJR: 0.568, h-index: 64)
Bioengineering & Translational Medicine     Open Access  
BioEssays     Hybrid Journal   (Followers: 10, SJR: 3.104, h-index: 155)
Bioethics     Hybrid Journal   (Followers: 14, SJR: 0.686, h-index: 39)
Biofuels, Bioproducts and Biorefining     Hybrid Journal   (Followers: 1, SJR: 1.725, h-index: 56)
Biological J. of the Linnean Society     Hybrid Journal   (Followers: 18, SJR: 1.172, h-index: 90)
Biological Reviews     Hybrid Journal   (Followers: 5, SJR: 6.469, h-index: 114)
Biologie in Unserer Zeit (Biuz)     Hybrid Journal   (Followers: 41, SJR: 0.12, h-index: 1)
Biology of the Cell     Full-text available via subscription   (Followers: 9, SJR: 1.812, h-index: 69)
Biomedical Chromatography     Hybrid Journal   (Followers: 6, SJR: 0.572, h-index: 49)
Biometrical J.     Hybrid Journal   (Followers: 5, SJR: 0.784, h-index: 44)
Biometrics     Hybrid Journal   (Followers: 37, SJR: 1.906, h-index: 96)
Biopharmaceutics and Drug Disposition     Hybrid Journal   (Followers: 10, SJR: 0.715, h-index: 44)
Biopolymers     Hybrid Journal   (Followers: 18, SJR: 1.199, h-index: 104)
Biotechnology and Applied Biochemistry     Hybrid Journal   (Followers: 44, SJR: 0.415, h-index: 55)
Biotechnology and Bioengineering     Hybrid Journal   (Followers: 157, SJR: 1.633, h-index: 146)
Biotechnology J.     Hybrid Journal   (Followers: 14, SJR: 1.185, h-index: 51)
Biotechnology Progress     Hybrid Journal   (Followers: 39, SJR: 0.736, h-index: 101)
Biotropica     Hybrid Journal   (Followers: 20, SJR: 1.374, h-index: 71)
Bipolar Disorders     Hybrid Journal   (Followers: 9, SJR: 2.592, h-index: 100)
Birth     Hybrid Journal   (Followers: 38, SJR: 0.763, h-index: 64)
Birth Defects Research Part A : Clinical and Molecular Teratology     Hybrid Journal   (Followers: 2, SJR: 0.727, h-index: 77)
Birth Defects Research Part B: Developmental and Reproductive Toxicology     Hybrid Journal   (Followers: 7, SJR: 0.468, h-index: 47)
Birth Defects Research Part C : Embryo Today : Reviews     Hybrid Journal   (SJR: 1.513, h-index: 55)
BJOG : An Intl. J. of Obstetrics and Gynaecology     Partially Free   (Followers: 248, SJR: 2.083, h-index: 125)

        1 2 3 4 5 6 7 8 | Last   [Sort by number of followers]   [Restore default list]

Journal Cover Aging Cell
  [SJR: 4.374]   [H-I: 95]   [11 followers]  Follow
    
  This is an Open Access Journal Open Access journal
   ISSN (Print) 1474-9718 - ISSN (Online) 1474-9726
   Published by John Wiley and Sons Homepage  [1592 journals]
  • Amyloid-beta 1-40 is associated with alterations in NG2+ pericyte
           population ex vivo and in vitro

    • Authors: Nina Schultz; Kristoffer Brännström, Elin Byman, Simon Moussaud, Henrietta M. Nielsen, , Anders Olofsson, Malin Wennström
      Abstract: The population of brain pericytes, a cell type important for vessel stability and blood brain barrier function, has recently been shown altered in patients with Alzheimer's disease (AD). The underlying reason for this alteration is not fully understood, but progressive accumulation of the AD characteristic peptide amyloid-beta (Aβ) has been suggested as a potential culprit. In the current study, we show reduced number of hippocampal NG2+ pericytes and an association between NG2+ pericyte numbers and Aβ1-40 levels in AD patients. We further demonstrate, using in vitro studies, an aggregation-dependent impact of Aβ1-40 on human NG2+ pericytes. Fibril-EP Aβ1-40 exposure reduced pericyte viability and proliferation and increased caspase 3/7 activity. Monomer Aβ1-40 had quite the opposite effect: increased pericyte viability and proliferation and reduced caspase 3/7 activity. Oligomer-EP Aβ1-40 had no impact on either of the cellular events. Our findings add to the growing number of studies suggesting a significant impact on pericytes in the brains of AD patients and suggest different aggregation forms of Aβ1-40 as potential key regulators of the brain pericyte population size.
      PubDate: 2018-02-17T00:06:43.672637-05:
      DOI: 10.1111/acel.12728
       
  • The SCN9A channel and plasma membrane depolarization promote cellular
           senescence through Rb pathway

    • Authors: Marine Warnier; Jean-Michel Flaman, Christophe Chouabe, Clotilde Wiel, Baptiste Gras, Audrey Griveau, Elena Blanc, Jean-Philippe Foy, Pauline Mathot, Pierre Saintigny, Fabien Van Coppenolle, David Vindrieux, Nadine Martin, David Bernard
      Abstract: Oncogenic signals lead to premature senescence in normal human cells causing a proliferation arrest and the elimination of these defective cells by immune cells. Oncogene-induced senescence (OIS) prevents aberrant cell division and tumor initiation. In order to identify new regulators of OIS, we performed a loss-of-function genetic screen and identified that the loss of SCN9A allowed cells to escape from OIS. The expression of this sodium channel increased in senescent cells during OIS. This upregulation was mediated by NF-κB transcription factors, which are well-known regulators of senescence. Importantly, the induction of SCN9A by an oncogenic signal or by p53 activation led to plasma membrane depolarization, which in turn, was able to induce premature senescence. Computational and experimental analyses revealed that SCN9A and plasma membrane depolarization mediated the repression of mitotic genes through a calcium/Rb/E2F pathway to promote senescence. Taken together, our work delineates a new pathway, which involves the NF-κB transcription factor, SCN9A expression, plasma membrane depolarization, increased calcium, the Rb/E2F pathway and mitotic gene repression in the regulation of senescence. This work thus provides new insight into the involvement of ion channels and plasma membrane potential in the control of senescence.
      PubDate: 2018-02-15T05:01:09.956112-05:
      DOI: 10.1111/acel.12736
       
  • Overexpression of PGC-1α in aging muscle enhances a subset of
           young-like molecular patterns

    • Authors: Sofia Garcia; Nadee Nissanka, Edson A. Mareco, Susana Rossi, Susana Peralta, Francisca Diaz, Richard L. Rotundo, Robson F. Carvalho, Carlos T. Moraes
      Abstract: PGC-1α is a transcriptional co-activator known as the master regulator of mitochondrial biogenesis. Its control of metabolism has been suggested to exert critical influence in the aging process. We have aged mice overexpressing PGC-1α in skeletal muscle to determine whether the transcriptional changes reflected a pattern of expression observed in younger muscle. Analyses of muscle proteins showed that Pax7 and several autophagy markers were increased. In general, the steady-state levels of several muscle proteins resembled that of muscle from young mice. Age-related mtDNA deletion levels were not increased by the PGC-1α-associated increase in mitochondrial biogenesis. Accordingly, age-related changes in the neuromuscular junction were minimized by PGC-1α overexpression. RNA-Seq showed that several genes overexpressed in the aged PGC-1α transgenic are expressed at higher levels in young when compared to aged skeletal muscle. As expected, there was increased expression of genes associated with energy metabolism but also of pathways associated with muscle integrity and regeneration. We also found that PGC-1α overexpression had a mild but significant effect on longevity. Taken together, overexpression of PGC-1α in aged muscle led to molecular changes that resemble the patterns observed in skeletal muscle from younger mice.
      PubDate: 2018-02-10T00:07:25.026691-05:
      DOI: 10.1111/acel.12707
       
  • Effects of 2 years of caloric restriction on oxidative status assessed by
           urinary F2-isoprostanes: The CALERIE 2 randomized clinical trial

    • Authors: Dora Il'yasova; Luigi Fontana, Manjushri Bhapkar, Carl F. Pieper, Ivan Spasojevic, Leanne M. Redman, Sai Krupa Das, Kim M. Huffman, William E. Kraus,
      Abstract: Calorie restriction (CR) without malnutrition slows aging in animal models. Oxidative stress reduction was proposed to mediate CR effects. CR effect on urinary F2-isoprostanes, validated oxidative stress markers, was assessed in CALERIE, a two-year randomized controlled trial. Healthy volunteers (n = 218) were randomized to prescribed 25% CR (n = 143) or ad libitum control (AL, n = 75) stratifying the randomization schedule by site, sex, and BMI. F2-isoprostanes were quantified using LC-MS/MS in morning, fasted urine specimens at baseline, at 12 and 24 months. The primary measure of oxidative status was creatinine-adjusted 2,3-dinor-iPF(2α)-III concentration, additional measured included iPF(2α)-III, iPF2a-VI, and 8,12-iso-iPF2a-VI. Intention-to-treat analyses assessed change in 2,3-dinor-iPF(2α)-III using mixed models assessing treatment, time, and treatment-by-time interaction effects, adjusted for blocking variables and baseline F2-isoprostane value. Exploratory analyses examined changes in iPF(2α)-III, iPF(2α)-VI, and 8,12-iso-iPF(2α)-VI. A factor analysis used aggregate information on F2-isoprostane values. In CR group, 2,3-dinor-iPF(2α)-III concentrations were reduced from baseline by 17% and 13% at 12 and 24 months, respectively; these changes were significantly different from AL group (p 
      PubDate: 2018-02-09T05:45:24.161737-05:
      DOI: 10.1111/acel.12719
       
  • Transcriptomics of aged Drosophila motor neurons reveals a matrix
           metalloproteinase that impairs motor function

    • Authors: Jorge Azpurua; Rebekah E. Mahoney, Benjamin A. Eaton
      Abstract: The neuromuscular junction (NMJ) is responsible for transforming nervous system signals into motor behavior and locomotion. In the fruit fly Drosophila melanogaster, an age-dependent decline in motor function occurs, analogous to the decline experienced in mice, humans, and other mammals. The molecular and cellular underpinnings of this decline are still poorly understood. By specifically profiling the transcriptome of Drosophila motor neurons across age using custom microarrays, we found that the expression of the matrix metalloproteinase 1 (dMMP1) gene reproducibly increased in motor neurons in an age-dependent manner. Modulation of physiological aging also altered the rate of dMMP1 expression, validating dMMP1 expression as a bona fide aging biomarker for motor neurons. Temporally controlled overexpression of dMMP1 specifically in motor neurons was sufficient to induce deficits in climbing behavior and cause a decrease in neurotransmitter release at neuromuscular synapses. These deficits were reversible if the dMMP1 expression was shut off again immediately after the onset of motor dysfunction. Additionally, repression of dMMP1 enzymatic activity via overexpression of a tissue inhibitor of metalloproteinases delayed the onset of age-dependent motor dysfunction. MMPs are required for proper tissue architecture during development. Our results support the idea that matrix metalloproteinase 1 is acting as a downstream effector of antagonistic pleiotropy in motor neurons and is necessary for proper development, but deleterious when reactivated at an advanced age.
      PubDate: 2018-02-07T00:07:52.675702-05:
      DOI: 10.1111/acel.12729
       
  • Treatment with the mitochondrial-targeted antioxidant peptide SS-31
           rescues neurovascular coupling responses and cerebrovascular endothelial
           function and improves cognition in aged mice

    • Authors: Stefano Tarantini; Noa M. Valcarcel-Ares, Andriy Yabluchanskiy, Gabor A. Fulop, Peter Hertelendy, Tripti Gautam, Eszter Farkas, Aleksandra Perz, Peter S. Rabinovitch, William E. Sonntag, Anna Csiszar, Zoltan Ungvari
      Abstract: Moment-to-moment adjustment of cerebral blood flow (CBF) via neurovascular coupling has an essential role in maintenance of healthy cognitive function. In advanced age, increased oxidative stress and cerebromicrovascular endothelial dysfunction impair neurovascular coupling, likely contributing to age-related decline of higher cortical functions. There is increasing evidence showing that mitochondrial oxidative stress plays a critical role in a range of age-related cellular impairments, but its role in neurovascular uncoupling remains unexplored. This study was designed to test the hypothesis that attenuation of mitochondrial oxidative stress may exert beneficial effects on neurovascular coupling responses in aging. To test this hypothesis, 24-month-old C57BL/6 mice were treated with a cell-permeable, mitochondria-targeted antioxidant peptide (SS-31; 10 mg kg−1 day−1, i.p.) or vehicle for 2 weeks. Neurovascular coupling was assessed by measuring CBF responses (laser speckle contrast imaging) evoked by contralateral whisker stimulation. We found that neurovascular coupling responses were significantly impaired in aged mice. Treatment with SS–31 significantly improved neurovascular coupling responses by increasing NO-mediated cerebromicrovascular dilation, which was associated with significantly improved spatial working memory, motor skill learning, and gait coordination. These findings are paralleled by the protective effects of SS–31 on mitochondrial production of reactive oxygen species and mitochondrial respiration in cultured cerebromicrovascular endothelial cells derived from aged animals. Thus, mitochondrial oxidative stress contributes to age-related cerebromicrovascular dysfunction, exacerbating cognitive decline. We propose that mitochondria-targeted antioxidants may be considered for pharmacological microvascular protection for the prevention/treatment of age-related vascular cognitive impairment (VCI).
      PubDate: 2018-02-06T01:31:21.828605-05:
      DOI: 10.1111/acel.12731
       
  • Smurf2 regulates stability and the autophagic–lysosomal turnover of
           lamin A and its disease-associated form progerin

    • Authors: Aurora Paola Borroni; Andrea Emanuelli, Pooja Anil Shah, Nataša Ilić, Liat Apel-Sarid, Biagio Paolini, Dhanoop Manikoth Ayyathan, Praveen Koganti, Gal Levy-Cohen, Michael Blank
      Abstract: A-lamins, encoded by the LMNA gene, are major structural components of the nuclear lamina coordinating essential cellular processes. Mutations in the LMNA gene and/or alterations in its expression levels have been linked to a distinct subset of human disorders, collectively known as laminopathies, and to cancer. Mechanisms regulating A-lamins are mostly obscure. Here, we identified E3 ubiquitin ligase Smurf2 as a physiological regulator of lamin A and its disease-associated mutant form progerin (LAΔ50), whose expression underlies the development of Hutchinson-Gilford progeria syndrome (HGPS), a devastating premature aging syndrome. We show that Smurf2 directly binds, ubiquitinates, and negatively regulates the expression of lamin A and progerin in Smurf2 dose- and E3 ligase-dependent manners. Overexpression of catalytically active Smurf2 promotes the autophagic–lysosomal breakdown of lamin A and progerin, whereas Smurf2 depletion increases lamin A levels. Remarkably, acute overexpression of Smurf2 in progeria fibroblasts was able to significantly reduce the nuclear deformability. Furthermore, we demonstrate that the reciprocal relationship between Smurf2 and A-lamins is preserved in different types of mouse and human normal and cancer tissues. These findings establish Smurf2 as an essential regulator of lamin A and progerin and lay a foundation for evaluating the efficiency of progerin clearance by Smurf2 in HGPS, and targeting of the Smurf2–lamin A axis in age-related diseases such as cancer.
      PubDate: 2018-02-05T20:46:35.50714-05:0
      DOI: 10.1111/acel.12732
       
  • High-throughput serum proteomics for the identification of protein
           biomarkers of mortality in older men

    • Authors: Eric S. Orwoll; Jack Wiedrick, Jon Jacobs, Erin S. Baker, Paul Piehowski, Vladislav Petyuk, Yuqian Gao, Tujin Shi, Richard D. Smith, Douglas C. Bauer, Steven R Cummings, Carrie M. Nielson, Jodi Lapidus,
      Abstract: The biological perturbations associated with incident mortality are not well elucidated, and there are limited biomarkers for the prediction of mortality. We used a novel high-throughput proteomics approach to identify serum peptides and proteins associated with 5-year mortality in community-dwelling men age ≥65 years who participated in a longitudinal observational study of musculoskeletal aging (Osteoporotic Fractures in Men: MrOS). In a discovery phase, serum specimens collected at baseline in 2473 men were analyzed using liquid chromatography–ion mobility–mass spectrometry, and incident mortality in the subsequent 5 years was ascertained by tri-annual questionnaire. Rigorous statistical methods were utilized to identify 56 peptides (31 proteins) that were associated with 5-year mortality. In an independent replication phase, selected reaction monitoring was used to examine 21 of those peptides in baseline serum from 750 additional men; 81% of those peptides remained significantly associated with mortality. Mortality-associated proteins included a variety involved in inflammation or complement activation; several have been previously linked to mortality (e.g., C-reactive protein, alpha 1-antichymotrypsin) and others are not previously known to be associated with mortality. Other novel proteins of interest included pregnancy-associated plasma protein, VE-cadherin, leucine-rich α-2 glycoprotein 1, vinculin, vitronectin, mast/stem cell growth factor receptor, and Saa4. A panel of peptides improved the predictive value of a commonly used clinical predictor of mortality. Overall, these results suggest that complex inflammatory pathways, and proteins in other pathways, are linked to 5-year mortality risk. This work may serve to identify novel biomarkers for near-term mortality.
      PubDate: 2018-02-05T03:35:36.56567-05:0
      DOI: 10.1111/acel.12717
       
  • Aging affects the in vivo regenerative potential of human
           mesoangioblasts

    • Authors: Alessio Rotini; Ester Martínez-Sarrà, Robin Duelen, Domiziana Costamagna, Ester Sara Di Filippo, Giorgia Giacomazzi, Hanne Grosemans, Stefania Fulle, Maurilio Sampaolesi
      Abstract: Sarcopenia is the age-related loss of muscle mass, strength, and function. Although the role of human satellite cells (SCs) as adult skeletal muscle stem cells has been deeply investigated, little is known about the impact of aging on muscle interstitial stem cells. Here, we isolated the non-SC CD56– fraction from human muscle biopsies of young and elderly subjects. The elderly interstitial cell population contained a higher number of CD15+ and PDGFRα+ cells when compared to young samples. In addition, we found that the CD56–/ALP+ cells were well represented as a multipotent stem cell population inside the CD56– fraction. CD56–/ALP+/CD15– cells were clonogenic, and since they were myogenic and expressed NG2, α-SMA and PDGFRβ can be considered mesoangioblasts (MABs). Interestingly, elderly MABs displayed a dramatic impairment in the myogenic differentiation ability in vitro and when transplanted in dystrophic immunodeficient Sgcb-null Rag2-null γc-null mice. In addition, elderly MABs proliferated less, but yet retained other multilineage capabilities. Overall, our results indicate that aging negatively impacted on the regenerative potential of MABs and this should be carefully considered for potential therapeutic applications of MABs.
      PubDate: 2018-02-04T00:10:19.871692-05:
      DOI: 10.1111/acel.12714
       
  • α-Motor neurons are spared from aging while their synaptic inputs
           degenerate in monkeys and mice

    • Authors: Nicholas Maxwell; Ryan W. Castro, Natalia M. Sutherland, Kelli L. Vaughan, Mark D. Szarowicz, Rafael Cabo, Julie A. Mattison, Gregorio Valdez
      Abstract: Motor function deteriorates with advancing age, increasing the risk of adverse health outcomes. While it is well established that skeletal muscles and neuromuscular junctions (NMJs) degenerate with increasing age, the effect of aging on α-motor neurons and their innervating synaptic inputs remains largely unknown. In this study, we examined the soma of α-motor neurons and innervating synaptic inputs in the spinal cord of aged rhesus monkeys and mice, two species with vastly different lifespans. We found that, in both species, α-motor neurons retain their soma size despite an accumulation of large amounts of cellular waste or lipofuscin. Interestingly, the lipofuscin profile varied considerably, indicating that α-motor neurons age at different rates. Although the rate of aging varies, α-motor neurons do not atrophy in old age. In fact, there is no difference in the number of motor axons populating ventral roots in old mice compared to adult mice. Moreover, the transcripts and proteins associated with α-motor neurons do not decrease in the spinal cord of old mice. However, in aged rhesus monkeys and mice, there were fewer cholinergic and glutamatergic synaptic inputs directly abutting α-motor neurons, evidence that aging causes α-motor neurons to shed synaptic inputs. Thus, the loss of synaptic inputs may contribute to age-related dysfunction of α-motor neurons. These findings broaden our understanding of the degeneration of the somatic motor system that precipitates motor dysfunction with advancing age.
      PubDate: 2018-02-04T00:06:40.858213-05:
      DOI: 10.1111/acel.12726
       
  • Emerging roles of extracellular vesicles in cellular senescence and aging

    • Authors: Masaki Takasugi
      Abstract: Cellular senescence is a cellular program that prevents the proliferation of cells at risk of neoplastic transformation. On the other hand, age-related accumulation of senescent cells promotes aging at least partially due to the senescence-associated secretory phenotype, whereby cells secrete high levels of inflammatory cytokines, chemokines, and matrix metalloproteinases. Emerging evidence, however, indicates that extracellular vesicles (EVs) are important mediators of the effects of senescent cells on their microenvironment. Senescent cells secrete more EphA2 and DNA via EVs, which can promote cancer cell proliferation and inflammation, respectively. Extracellular vesicles secreted from DNA-damaged cells can also affect telomere regulation. Furthermore, it has now become clear that EVs actually play important roles in many aspects of aging. This review is intended to summarize these recent progresses, with emphasis on relationships between cellular senescence and EVs.
      PubDate: 2018-02-01T21:16:53.948669-05:
      DOI: 10.1111/acel.12734
       
  • Ablation of PPARγ in subcutaneous fat exacerbates age-associated
           obesity and metabolic decline

    • Authors: Lingyan Xu; Xinran Ma, Narendra Kumar Verma, Dongmei Wang, Oksana Gavrilova, Richard L. Proia, Toren Finkel, Elisabetta Mueller
      Abstract: It is well established that aging is associated with metabolic dysfunction such as increased adiposity and impaired energy dissipation; however, the transcriptional mechanisms regulating energy balance during late life stages have not yet been fully elucidated. Here, we show that ablation of the nuclear receptor PPARγ specifically in inguinal fat tissue in aging mice is associated with increased fat tissue expansion and insulin resistance. These metabolic effects are accompanied by decreased thermogenesis, reduced levels of brown fat genes, and browning of subcutaneous adipose tissue. Comparative studies of the effects of PPARγ downregulation in young and mid-aged mice demonstrate a preferential regulation of brown fat gene programs in inguinal fat in an age-dependent manner. In conclusion, our study uncovers an essential role for PPARγ in maintaining energy expenditure during the aging process and suggests the possibility of targeting PPARγ to counteract age-associated metabolic dysfunction.
      PubDate: 2018-01-31T00:09:49.255433-05:
      DOI: 10.1111/acel.12721
       
  • Metformin regulates metabolic and nonmetabolic pathways in skeletal muscle
           and subcutaneous adipose tissues of older adults

    • Authors: Ameya S Kulkarni; Erika F Brutsaert, Valentin Anghel, Kehao Zhang, Noah Bloomgarden, Michael Pollak, Jessica C Mar, Meredith Hawkins, Jill P Crandall, Nir Barzilai
      Abstract: Administration of metformin increases healthspan and lifespan in model systems, and evidence from clinical trials and observational studies suggests that metformin delays a variety of age-related morbidities. Although metformin has been shown to modulate multiple biological pathways at the cellular level, these pleiotropic effects of metformin on the biology of human aging have not been studied. We studied ~70-year-old participants (n = 14) in a randomized, double-blind, placebo-controlled, crossover trial in which they were treated with 6 weeks each of metformin and placebo. Following each treatment period, skeletal muscle and subcutaneous adipose tissue biopsies were obtained, and a mixed-meal challenge test was performed. As expected, metformin therapy lowered 2-hour glucose, insulin AUC, and insulin secretion compared to placebo. Using FDR
      PubDate: 2018-01-31T00:09:01.377461-05:
      DOI: 10.1111/acel.12723
       
  • Long-lasting pathological consequences of overexpression-induced
           α-synuclein spreading in the rat brain

    • Authors: Raffaella Rusconi; Ayse Ulusoy, Helia Aboutalebi, Donato A. Di Monte
      Abstract: Increased expression of α-synuclein can initiate its long-distance brain transfer, representing a potential mechanism for pathology spreading in age-related synucleinopathies, such as Parkinson's disease. In this study, the effects of overexpression-induced α-synuclein transfer were assessed over a 1-year period after injection of viral vectors carrying human α-synuclein DNA into the rat vagus nerve. This treatment causes targeted overexpression within neurons in the dorsal medulla oblongata and subsequent diffusion of the exogenous protein toward more rostral brain regions. Protein advancement and accumulation in pontine, midbrain, and forebrain areas were contingent upon continuous overexpression, because death of transduced medullary neurons resulted in cessation of spreading. Lack of sustained spreading did not prevent the development of long-lasting pathological changes. Particularly remarkable were findings in the locus coeruleus, a pontine nucleus with direct connections to the dorsal medulla oblongata and greatly affected by overexpression-induced transfer in this model. Data revealed progressive degeneration of catecholaminergic neurons that proceeded long beyond the time of spreading cessation. Neuronal pathology in the locus coeruleus was accompanied by pronounced microglial activation and, at later times, astrocytosis. Interestingly, microglial activation was also featured in another region reached by α-synuclein transfer, the central amygdala, even in the absence of frank neurodegeneration. Thus, overexpression-induced spreading, even if temporary, causes long-lasting pathological consequences in brain regions distant from the site of overexpression but anatomically connected to it. Neurodegeneration may be a consequence of severe protein burden, whereas even a milder α-synuclein accumulation in tissues affected by protein transfer could induce sustained microglial activation.
      PubDate: 2018-01-30T21:41:51.751945-05:
      DOI: 10.1111/acel.12727
       
  • ATF3 represses PINK1 gene transcription in lung epithelial cells to
           control mitochondrial homeostasis

    • Authors: Marta Bueno; Judith Brands, Lauren Voltz, Kaitlin Fiedler, Brenton Mays, Claudette St. Croix, John Sembrat, Rama K. Mallampalli, Mauricio Rojas, Ana L. Mora
      Abstract: PINK1 (PTEN-induced putative kinase 1) is a key regulator of mitochondrial homeostasis that is relatively depleted in aging lungs and in lung epithelial cells from patients with idiopathic pulmonary fibrosis (IPF), a disease linked with aging. Impaired PINK1 expression and accumulation of damaged mitochondria in lung epithelial cells from fibrotic lungs were associated with the presence of ER stress. Here, we show that ATF3 (activating transcription factor 3), a member of the integrated stress response (ISR), negatively regulates transcription of the PINK1 gene. An ATF3 binding site within the human PINK1 promoter is located in the first 150 bp upstream of the transcription start site. Induction of ER stress or overexpression of ATF3 inhibited the activity of the PINK1 promoter. Importantly, overexpression of ATF3 causes accumulation of depolarized mitochondria, increased production of mitochondrial ROS, and loss of cell viability. Furthermore, conditional deletion of ATF3 in type II lung epithelial cells protects mice from bleomycin-induced lung fibrosis. Finally, we observed that ATF3 expression increases in the lung with age and, specially, in lung epithelial cells from IPF lungs. These data provide a unique link between ATF3 and PINK1 expression suggesting that persistent stress, driven by ATF3, can dysregulate mitochondrial homeostasis by repression of PINK1 mRNA synthesis.
      PubDate: 2018-01-24T00:07:18.030125-05:
      DOI: 10.1111/acel.12720
       
  • Skeletal muscle ex vivo mitochondrial respiration parallels decline
           in vivo oxidative capacity, cardiorespiratory fitness, and muscle
           strength: The Baltimore Longitudinal Study of Aging

    • Authors: Marta Gonzalez-Freire; Paul Scalzo, Jarod D'Agostino, Zenobia A. Moore, Alberto Diaz-Ruiz, Elisa Fabbri, Ariel Zane, Brian Chen, Kevin G. Becker, Elin Lehrmann, Linda Zukley, Chee W. Chia, Toshiko Tanaka, Paul M. Coen, Michel Bernier, Rafael Cabo, Luigi Ferrucci
      Abstract: Mitochondrial function in human skeletal muscle declines with age. Most evidence for this decline comes from studies that assessed mitochondrial function indirectly, and the impact of such deterioration with respect to physical function has not been clearly delineated. We hypothesized that mitochondrial respiration in permeabilized human muscle fibers declines with age and correlates with phosphocreatine postexercise recovery rate (kPCr), muscle performance, and aerobic fitness. Mitochondrial respiration was assessed by high-resolution respirometry in saponin-permeabilized fibers from vastus lateralis muscle biopsies of 38 participants from the Baltimore Longitudinal Study of Aging (BLSA; 21 men, age 24–91 years) who also had available measures of peak oxygen consumption (VO2max) from treadmill tests, gait speed in different tasks, 31P magnetic resonance spectroscopy, isokinetic knee extension, and grip strength. Results indicated a significant reduction in mitochondrial respiration with age (p 
      PubDate: 2018-01-21T22:30:29.587492-05:
      DOI: 10.1111/acel.12725
       
  • T-cell Immunoglobulin and ITIM Domain Contributes to CD8+ T-cell
           Immunosenescence

    • Authors: Yangzi Song; Beibei Wang, Rui Song, Yu Hao, Di Wang, Yuxin Li, Yu Jiang, Ling Xu, Yaluan Ma, Hong Zheng, Yaxian Kong, Hui Zeng
      Abstract: Aging is associated with immune dysfunction, especially T-cell defects, which result in increased susceptibility to various diseases. Previous studies showed that T cells from aged mice express multiple inhibitory receptors, providing evidence of the relationship between T-cell exhaustion and T-cell senescence. In this study, we showed that T-cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif (ITIM) domain (TIGIT), a novel co-inhibitory receptor, was upregulated in CD8+ T cells of elderly adults. Aged TIGIT+ CD8+ T cells expressed high levels of other inhibitory receptors including PD-1 and exhibited features of exhaustion such as downregulation of the key costimulatory receptor CD28, representative intrinsic transcriptional regulation, low production of cytokines, and high susceptibility to apoptosis. Importantly, their functional defects associated with aging were reversed by TIGIT knockdown. CD226 downregulation on aged TIGIT+ CD8+ T cells is likely involved in TIGIT-mediated negative immune suppression. Collectively, our findings indicated that TIGIT acts as a critical immune regulator during aging, providing a strong rationale for targeting TIGIT to improve dysfunction related to immune system aging.
      PubDate: 2018-01-19T00:05:52.112757-05:
      DOI: 10.1111/acel.12716
       
  • Corrigendum

    • PubDate: 2018-01-17T05:58:51.605841-05:
      DOI: 10.1111/acel.12712
       
  • Issue Information

    • PubDate: 2018-01-17T05:58:46.545748-05:
      DOI: 10.1111/acel.12667
       
  • Senescence chips for ultrahigh-throughput isolation and removal of
           senescent cells

    • Authors: Yuchao Chen; Pan Mao, Antoine M. Snijders, Daojing Wang
      Abstract: Cellular senescence plays an important role in organismal aging and age-related diseases. However, it is challenging to isolate low numbers of senescent cells from small volumes of biofluids for downstream analysis. Furthermore, there is no technology that could selectively remove senescent cells in a high-throughput manner. In this work, we developed a novel microfluidic chip platform, termed senescence chip, for ultrahigh-throughput isolation and removal of senescent cells. The core component of our senescence chip is a slanted and tunable 3D micropillar array with a variety of shutters in the vertical direction for rapid cell sieving, taking advantage of the characteristic cell size increase during cellular senescence. The 3D configuration achieves high throughput, high recovery rate, and device robustness with minimum clogging. We demonstrated proof-of-principle applications in isolation and enumeration of senescent mesenchymal stem cells (MSCs) from undiluted human whole blood, and senescent cells from mouse bone marrow after total body irradiation, with the single-cell resolution. After scale-up to a multilayer and multichannel structure, our senescence chip achieved ultrahigh-throughput removal of senescent cells from human whole blood with an efficiency of over 70% at a flow rate of 300 ml/hr. Sensitivity and specificity of our senescence chips could be augmented with implementation of multiscale size separation, and identification of background white blood cells using their cell surface markers such as CD45. With the advantages of high throughput, robustness, and simplicity, our senescence chips may find wide applications and contribute to diagnosis and therapeutic targeting of cellular senescence.
      PubDate: 2018-01-16T04:06:06.365973-05:
      DOI: 10.1111/acel.12722
       
  • Endothelium-specific CYP2J2 overexpression attenuates age-related insulin
           resistance

    • Authors: Yan Yang; Ruolan Dong, Zhihui Chen, Danli Hu, Menglu Fu, Ying Tang, Dao Wen Wang, Xizhen Xu, Ling Tu
      Abstract: Ample evidences demonstrate that cytochrome P450 epoxygenase-derived epoxyeicosatrienoic acids (EETs) exert diverse biological activities, which include potent vasodilatory, anti-inflammatory, and cardiovascular protective effects. In this study, we investigated the effects of endothelium-specific CYP2J2 overexpression on age-related insulin resistance and metabolic dysfunction. Endothelium-specific targeting of the human CYP epoxygenase, CYP2J2, transgenic mice (Tie2-CYP2J2-Tr mice) was utilized. The effects of endothelium-specific CYP2J2 overexpression on aging-associated obesity, inflammation, and peripheral insulin resistance were evaluated by assessing metabolic parameters in young (3 months old) and aged (16 months old) adult male Tie2-CYP2J2-Tr mice. Decreased insulin sensitivity and attenuated insulin signaling in aged skeletal muscle, adipose tissue, and liver were observed in aged adult male mice, and moreover, these effects were partly inhibited in 16-month-old CYP2J2-Tr mice. In addition, CYP2J2 overexpression-mediated insulin sensitization in aged mice was associated with the amelioration of inflammatory state. Notably, the aging-associated increases in fat mass and adipocyte size were only observed in 16-month-old wild-type mice, and CYP2J2 overexpression markedly prevented the increase in fat mass and adipocyte size in aged Tie2-CYP2J2-Tr mice, which was associated with increased energy expenditure and decreased lipogenic genes expression. Furthermore, these antiaging phenotypes of Tie2-CYP2J2-Tr mice were also associated with increased muscle blood flow, enhanced active-phase locomotor activity, and improved mitochondrial dysfunction in skeletal muscle. Collectively, our findings indicated that endothelium-specific CYP2J2 overexpression alleviated age-related insulin resistance and metabolic dysfunction, which highlighted CYP epoxygenase-EET system as a potential target for combating aging-related metabolic disorders.
      PubDate: 2018-01-10T04:44:06.548643-05:
      DOI: 10.1111/acel.12718
       
  • The mitochondrial ATP synthase is a shared drug target for aging and
           dementia

    • Authors: Joshua Goldberg; Antonio Currais, Marguerite Prior, Wolfgang Fischer, Chandramouli Chiruta, Eric Ratliff, Daniel Daugherty, Richard Dargusch, Kim Finley, Pau B. Esparza-Moltó, José M. Cuezva, Pamela Maher, Michael Petrascheck, David Schubert
      Abstract: Aging is a major driving force underlying dementia, such as that caused by Alzheimer's disease (AD). While the idea of targeting aging as a therapeutic strategy is not new, it remains unclear how closely aging and age-associated diseases are coupled at the molecular level. Here, we discover a novel molecular link between aging and dementia through the identification of the molecular target for the AD drug candidate J147. J147 was developed using a series of phenotypic screening assays mimicking disease toxicities associated with the aging brain. We have previously demonstrated the therapeutic efficacy of J147 in several mouse models of AD. Here, we identify the mitochondrial α-F1-ATP synthase (ATP5A) as a target for J147. By targeting ATP synthase, J147 causes an increase in intracellular calcium leading to sustained calcium/calmodulin-dependent protein kinase kinase β (CAMKK2)-dependent activation of the AMPK/mTOR pathway, a canonical longevity mechanism. Accordingly, modulation of mitochondrial processes by J147 prevents age-associated drift of the hippocampal transcriptome and plasma metabolome in mice and extends lifespan in drosophila. Our results link aging and age-associated dementia through ATP synthase, a molecular drug target that can potentially be exploited for the suppression of both. These findings demonstrate that novel screens for new AD drug candidates identify compounds that act on established aging pathways, suggesting an unexpectedly close molecular relationship between the two.
      PubDate: 2018-01-07T18:55:43.996245-05:
      DOI: 10.1111/acel.12715
       
  • UNC-120/SRF independently controls muscle aging and lifespan in
           Caenorhabditis elegans

    • Authors: Adeline Mergoud dit Lamarche; Laurent Molin, Laura Pierson, Marie-Christine Mariol, Jean-Louis Bessereau, Kathrin Gieseler, Florence Solari
      Abstract: Aging is commonly defined as the loss of global homeostasis, which results from progressive alteration of all organs function. This model is currently challenged by recent data showing that interventions that extend lifespan do not always increase the overall fitness of the organism. These data suggest the existence of tissue-specific factors that regulate the pace of aging in a cell-autonomous manner. Here, we investigated aging of Caenorhabditis elegans striated muscles at the subcellular and the physiological level. Our data show that muscle aging is characterized by a dramatic decrease in the expression of genes encoding proteins required for muscle contraction, followed by a change in mitochondria morphology, and an increase in autophagosome number. Myofilaments, however, remain unaffected during aging. We demonstrated that the conserved transcription factor UNC-120/SRF regulates muscle aging biomarkers. Interestingly, the role of UNC-120/SRF in the control of muscle aging can be dissociated from its broader effect on lifespan. In daf-2/insulin/IGF1 receptor mutants, which exhibit a delayed appearance of muscle aging biomarkers and are long-lived, disruption of unc-120 accelerates muscle aging but does not suppress the lifespan phenotype of daf-2 mutant. Conversely, unc-120 overexpression delays muscle aging but does not increase lifespan. Overall, we demonstrate that UNC-120/SRF controls the pace of muscle aging in a cell-autonomous manner downstream of the insulin/IGF1 receptor.
      PubDate: 2018-01-03T07:56:48.663558-05:
      DOI: 10.1111/acel.12713
       
  • Circulating levels of monocyte chemoattractant protein-1 as a potential
           measure of biological age in mice and frailty in humans

    • Authors: Matthew J. Yousefzadeh; Marissa J. Schafer, Nicole Noren Hooten, Elizabeth J. Atkinson, Michele K. Evans, Darren J. Baker, Ellen K. Quarles, Paul D. Robbins, Warren C. Ladiges, Nathan K. LeBrasseur, Laura J. Niedernhofer
      Abstract: A serum biomarker of biological versus chronological age would have significant impact on clinical care. It could be used to identify individuals at risk of early-onset frailty or the multimorbidities associated with old age. It may also serve as a surrogate endpoint in clinical trials targeting mechanisms of aging. Here, we identified MCP-1/CCL2, a chemokine responsible for recruiting monocytes, as a potential biomarker of biological age. Circulating monocyte chemoattractant protein-1 (MCP-1) levels increased in an age-dependent manner in wild-type (WT) mice. That age-dependent increase was accelerated in Ercc1−/Δ and Bubr1H/H mouse models of progeria. Genetic and pharmacologic interventions that slow aging of Ercc1−/Δ and WT mice lowered serum MCP-1 levels significantly. Finally, in elderly humans with aortic stenosis, MCP-1 levels were significantly higher in frail individuals compared to nonfrail. These data support the conclusion that MCP-1 can be used as a measure of mammalian biological age that is responsive to interventions that extend healthy aging.
      PubDate: 2017-12-31T00:05:44.966828-05:
      DOI: 10.1111/acel.12706
       
  • Senescence promotes in vivo reprogramming through p16INK4a and IL-6

    • Authors: Lluc Mosteiro; Cristina Pantoja, Alba Martino, Manuel Serrano
      Abstract: Cellular senescence is a damage response aimed to orchestrate tissue repair. We have recently reported that cellular senescence, through the paracrine release of interleukin-6 (IL6) and other soluble factors, strongly favors cellular reprogramming by Oct4, Sox2, Klf4, and c-Myc (OSKM) in nonsenescent cells. Indeed, activation of OSKM in mouse tissues triggers senescence in some cells and reprogramming in other cells, both processes occurring concomitantly and in close proximity. In this system, Ink4a/Arf-null tissues cannot undergo senescence, fail to produce IL6, and cannot reprogram efficiently; whereas p53-null tissues undergo extensive damage and senescence, produce high levels of IL6, and reprogram efficiently. Here, we have further explored the genetic determinants of in vivo reprogramming. We report that Ink4a, but not Arf, is necessary for OSKM-induced senescence and, thereby, for the paracrine stimulation of reprogramming. However, in the absence of p53, IL6 production and reprogramming become independent of Ink4a, as revealed by the analysis of Ink4a/Arf/p53 deficient mice. In the case of the cell cycle inhibitor p21, its protein levels are highly elevated upon OSKM activation in a p53-independent manner, and we show that p21-null tissues present increased levels of senescence, IL6, and reprogramming. We also report that Il6-mutant tissues are impaired in undergoing reprogramming, thus reinforcing the critical role of IL6 in reprogramming. Finally, young female mice present lower efficiency of in vivo reprogramming compared to male mice, and this gender difference disappears with aging, both observations being consistent with the known anti-inflammatory effect of estrogens. The current findings regarding the interplay between senescence and reprogramming may conceivably apply to other contexts of tissue damage.
      PubDate: 2017-12-27T01:16:14.808407-05:
      DOI: 10.1111/acel.12711
       
  • Plasticity of lifelong calorie-restricted C57BL/6J mice in adapting to a
           medium-fat diet intervention at old age

    • Authors: Fenni Rusli; Mark V. Boekschoten, Vincenzo Borelli, Chen Sun, Carolien Lute, Aswin L. Menke, Joost Heuvel, Stefano Salvioli, Claudio Franceschi, Michael Müller, Wilma T. Steegenga
      Abstract: Calorie restriction (CR) is a dietary regimen that supports healthy aging. In this study, we investigated the systemic and liver-specific responses caused by a diet switch to a medium-fat (MF) diet in 24-month-old lifelong, CR-exposed mice. This study aimed to increase the knowledge base on dietary alterations of gerontological relevance. Nine-week-old C57BL/6J mice were exposed either to a control, CR, or MF diet. At the age of 24 months, a subset of mice of the CR group was transferred to ad libitumMF feeding (CR-MF). The mice were sacrificed at the age of 28 months, and then, biochemical and molecular analyses were performed. Our results showed that, despite the long-term exposure to the CR regimen, mice in the CR-MF group displayed hyperphagia, rapid weight gain, and hepatic steatosis. However, no hepatic fibrosis/injury or alteration in CR-improved survival was observed in the diet switch group. The liver transcriptomic profile of CR-MF mice largely shifted to a profile similar to the MF-fed animals but leaving ~22% of the 1,578 differentially regulated genes between the CR and MF diet groups comparable with the expression of the lifelong CR group. Therefore, although the diet switch was performed at an old age, the CR-MF-exposed mice showed plasticity in coping with the challenge of a MF diet without developing severe liver pathologies.
      PubDate: 2017-12-21T00:08:09.670729-05:
      DOI: 10.1111/acel.12696
       
  • Movement decline across lifespan of Caenorhabditis elegans mutants in the
           insulin/insulin-like signaling pathway

    • Authors: Breanne L. Newell Stamper; James R. Cypser, Katerina Kechris, David Alan Kitzenberg, Patricia M. Tedesco, Thomas E. Johnson
      Abstract: Research in aging biology has identified several pathways that are molecularly conserved across species that extend lifespan when mutated. The insulin/insulin-like signaling (IIS) pathway is one of the most widely studied of these. It has been assumed that extending lifespan also extends healthspan (the period of life with minimal functional loss). However, data supporting this assumption conflict and recent evidence suggest that life extension may, in and of itself, extend the frail period. In this study, we use Caenorhabditis elegans to further probe the link between lifespan and healthspan. Using movement decline as a measure of health, we assessed healthspan across the entire lifespan in nine IIS pathway mutants. In one series of experiments, we studied healthspan in mass cultures, and in another series, we studied individuals longitudinally. We found that long-lived mutants display prolonged mid-life movement and do not prolong the frailty period. Lastly, we observed that early-adulthood movement was not predictive of late-life movement or survival, within identical phenotypes. Overall, these observations show that extending lifespan does not prolong the period of frailty. Both genotype and a stochastic component modulate aging, and movement late in life is more variable than early-life movement.
      PubDate: 2017-12-07T01:38:32.275976-05:
      DOI: 10.1111/acel.12704
       
  • Autophagy controls mesenchymal stem cell properties and senescence during
           bone aging

    • Authors: Yang Ma; Meng Qi, Ying An, Liqiang Zhang, Rui Yang, Daniel H Doro, Wenjia Liu, Yan Jin
      Abstract: Bone marrow-derived mesenchymal stem cells (BMMSCs) exhibit degenerative changes, including imbalanced differentiation and reduced proliferation during aging, that contribute to age-related bone loss. We demonstrate here that autophagy is significantly reduced in aged BMMSCs compared with young BMMSCs. The autophagy inhibitor 3-methyladenine (3-MA) could turn young BMMSCs into a relatively aged state by reducing their osteogenic differentiation and proliferation capacity and enhancing their adipogenic differentiation capacity. Accordingly, the autophagy activator rapamycin could restore the biological properties of aged BMMSCs by increasing osteogenic differentiation and proliferation capacity and decreasing adipogenic differentiation capacity. Possible underlying mechanisms were explored, and the analysis revealed that autophagy could affect reactive oxygen species and p53 levels, thus regulating biological properties of BMMSCs. In an in vivo study, we found that activation of autophagy restored bone loss in aged mice. In conclusion, our results suggest that autophagy plays a pivotal role in the aging of BMMSCs, and activation of autophagy could partially reverse this aging and may represent a potential therapeutic avenue to clinically treat age-related bone loss.
      PubDate: 2017-12-06T03:56:10.889032-05:
      DOI: 10.1111/acel.12709
       
  • Young plasma reverses age-dependent alterations in hepatic function
           through the restoration of autophagy

    • Authors: Anding Liu; Enshuang Guo, Jiankun Yang, Yan Yang, Shenpei Liu, Xiaojing Jiang, Qi Hu, Olaf Dirsch, Uta Dahmen, Cuntai Zhang, David A Gewirtz, Haoshu Fang
      Abstract: Recent studies showing the therapeutic effect of young blood on aging-associated deterioration of organs point to young blood as the solution for clinical problems related to old age. Given that defective autophagy has been implicated in aging and aging-associated organ injuries, this study was designed to determine the effect of young blood on aging-induced alterations in hepatic function and underlying mechanisms, with a focus on autophagy. Aged rats (22 months) were treated with pooled plasma (1 ml, intravenously) collected from young (3 months) or aged rats three times per week for 4 weeks, and 3-methyladenine or wortmannin was used to inhibit young blood-induced autophagy. Aging was associated with elevated levels of alanine transaminase and aspartate aminotransferase, lipofuscin accumulation, steatosis, fibrosis, and defective liver regeneration after partial hepatectomy, which were significantly attenuated by young plasma injections. Young plasma could also restore aging-impaired autophagy activity. Inhibition of the young plasma-restored autophagic activity abrogated the beneficial effect of young plasma against hepatic injury with aging. In vitro, young serum could protect old hepatocytes from senescence, and the antisenescence effect of young serum was abrogated by 3-methyladenine, wortmannin, or small interfering RNA to autophagy-related protein 7. Collectively, our data indicate that young plasma could ameliorate age-dependent alterations in hepatic function partially via the restoration of autophagy.
      PubDate: 2017-12-05T20:36:10.691556-05:
      DOI: 10.1111/acel.12708
       
  • FOXO protects against age-progressive axonal degeneration

    • Authors: Inah Hwang; Hwanhee Oh, Evan Santo, Do-Yeon Kim, John W. Chen, Roderick T. Bronson, Jason W. Locasale, Yoonmi Na, Jaclyn Lee, Stewart Reed, Miklos Toth, Wai H. Yu, Florian L. Muller, Jihye Paik
      Abstract: Neurodegeneration resulting in cognitive and motor impairment is an inevitable consequence of aging. Little is known about the genetic regulation of this process despite its overriding importance in normal aging. Here, we identify the Forkhead Box O (FOXO) transcription factor 1, 3, and 4 isoforms as a guardian of neuronal integrity by inhibiting age-progressive axonal degeneration in mammals. FOXO expression progressively increased in aging human and mouse brains. The nervous system-specific deletion of Foxo transcription factors in mice accelerates aging-related axonal tract degeneration, which is followed by motor dysfunction. This accelerated neurodegeneration is accompanied by levels of white matter astrogliosis and microgliosis in middle-aged Foxo knockout mice that are typically only observed in very old wild-type mice and other aged mammals, including humans. Mechanistically, axonal degeneration in nerve-specific Foxo knockout mice is associated with elevated mTORC1 activity and accompanying proteotoxic stress due to decreased Sestrin3 expression. Inhibition of mTORC1 by rapamycin treatment mimics FOXO action and prevented axonal degeneration in Foxo knockout mice with accelerated nervous system aging. Defining this central role for FOXO in neuroprotection during mammalian aging offers an invaluable window into the aging process itself.
      PubDate: 2017-11-26T16:51:27.68299-05:0
      DOI: 10.1111/acel.12701
       
  • 17α-estradiol acts through hypothalamic pro-opiomelanocortin expressing
           neurons to reduce feeding behavior

    • Authors: Frederik J. Steyn; Shyuan T. Ngo, Vicky Ping Chen, Lora C. Bailey-Downs, Teresa Y. Xie, Martin Ghadami, Stephen Brimijoin, Willard M. Freeman, Marcelo Rubinstein, Malcolm J. Low, Michael B. Stout
      Abstract: Weight loss is an effective intervention for diminishing disease burden in obese older adults. Pharmacological interventions that reduce food intake and thereby promote weight loss may offer effective strategies to reduce age-related disease. We previously reported that 17α-estradiol (17α-E2) administration elicits beneficial effects on metabolism and inflammation in old male mice. These observations were associated with reduced calorie intake. Here, we demonstrate that 17α-E2 acts through pro-opiomelanocortin (Pomc) expression in the arcuate nucleus (ARC) to reduce food intake and body mass in mouse models of obesity. These results confirm that 17α-E2 modulates appetite through selective interactions within hypothalamic anorexigenic pathways. Interestingly, some peripheral markers of metabolic homeostasis were also improved in animals with near complete loss of ARC Pomc transcription. This suggests that 17α-E2 might have central and peripheral actions that can beneficially affect metabolism cooperatively or independently.
      PubDate: 2017-11-23T00:28:24.674337-05:
      DOI: 10.1111/acel.12703
       
  • Comparative proteomic profiling reveals a role for Cisd2 in skeletal
           muscle aging

    • Authors: Yi-Long Huang; Zhao-Qing Shen, Chia-Yu Wu, Yuan-Chi Teng, Chen-Chung Liao, Cheng-Heng Kao, Liang-Kung Chen, Chao-Hsiung Lin, Ting-Fen Tsai
      Abstract: Skeletal muscle has emerged as one of the most important tissues involved in regulating systemic metabolism. The gastrocnemius is a powerful skeletal muscle composed of predominantly glycolytic fast-twitch fibers that are preferentially lost among old age. This decrease in gastrocnemius muscle mass is remarkable during aging; however, the underlying molecular mechanism is not fully understood. Strikingly, there is a ~70% decrease in Cisd2 protein, a key regulator of lifespan in mice and the disease gene for Wolfram syndrome 2 in humans, within the gastrocnemius after middle age among mice. A proteomics approach was used to investigate the gastrocnemius of naturally aged mice, and this was compared to the autonomous effect of Cisd2 on gastrocnemius aging using muscle-specific Cisd2 knockout (mKO) mice as a premature aging model. Intriguingly, dysregulation of calcium signaling and activation of UPR/ER stress stand out as the top two pathways. Additionally, the activity of Serca1 was significantly impaired and this impairment is mainly attributable to irreversibly oxidative modifications of Serca. Our results reveal that the overall characteristics of the gastrocnemius are very similar when naturally aged mice and the Cisd2 mKO mice are compared in terms of pathological alterations, ultrastructural abnormalities, and proteomics profiling. This suggests that Cisd2 mKO mouse is a unique model for understanding the aging mechanism of skeletal muscle. Furthermore, this work substantiates the hypothesis that Cisd2 is crucial to the gastrocnemius muscle and suggests that Cisd2 is a potential therapeutic target for muscle aging.
      PubDate: 2017-11-23T00:28:04.149909-05:
      DOI: 10.1111/acel.12705
       
  • DLP1-dependent mitochondrial fragmentation and redistribution mediate
           prion-associated mitochondrial dysfunction and neuronal death

    • Authors: Chaosi Li; Di Wang, Wei Wu, Wei Yang, Syed Zahid Ali Shah, Ying Zhao, Yuhan Duan, Lu Wang, Xiangmei Zhou, Deming Zhao, Lifeng Yang
      Abstract: Mitochondrial malfunction is a universal and critical step in the pathogenesis of many neurodegenerative diseases including prion diseases. Dynamin-like protein 1 (DLP1) is one of the key regulators of mitochondrial fission. In this study, we investigated the role of DLP1 in mitochondrial fragmentation and dysfunction in neurons using in vitro and in vivo prion disease models. Mitochondria became fragmented and redistributed from axons to soma, correlated with increased mitochondrial DLP1 expression in murine primary neurons (N2a cells) treated with the prion peptide PrP106–126 in vitro as well as in prion strain-infected hamster brain in vivo. Suppression of DLP1 expression by DPL1 RNAi inhibited prion-induced mitochondrial fragmentation and dysfunction (measured by ADP/ATP ratio, mitochondrial membrane potential, and mitochondrial integrity). We also demonstrated that DLP1 RNAi is neuroprotective against prion peptide in N2a cells as shown by improved cell viability and decreased apoptosis markers, caspase 3 induced by PrP106–126. On the contrary, overexpression of DLP1 exacerbated mitochondrial dysfunction and cell death. Moreover, inhibition of DLP1 expression ameliorated PrP106–126-induced neurite loss and synaptic abnormalities (i.e., loss of dendritic spine and PSD-95, a postsynaptic scaffolding protein as a marker of synaptic plasticity) in primary neurons, suggesting that altered DLP1 expression and mitochondrial fragmentation are upstream events that mediate PrP106–126-induced neuron loss and degeneration. Our findings suggest that DLP1-dependent mitochondrial fragmentation and redistribution plays a pivotal role in PrPSc-associated mitochondria dysfunction and neuron apoptosis. Inhibition of DLP1 may be a novel and effective strategy in the prevention and treatment of prion diseases.
      PubDate: 2017-11-22T19:15:44.04388-05:0
      DOI: 10.1111/acel.12693
       
  • Cellular aging dynamics after acute malaria infection: A 12-month
           longitudinal study

    • Authors: Muhammad Asghar; Victor Yman, Manijeh Vafa Homann, Klara Sondén, Ulf Hammar, Dennis Hasselquist, Anna Färnert
      Abstract: Accelerated cellular aging and reduced lifespan have recently been shown in birds chronically infected with malaria parasites. Whether malaria infection also affects cellular aging in humans has not been reported. Here, we assessed the effect of a single acute Plasmodium falciparum malaria infection on cellular aging dynamics in travelers prospectively followed over one year in Sweden. DNA and RNA were extracted from venous blood collected at the time of admission and repeatedly up to one year. Telomere length was measured using real-time quantitative PCR, while telomerase activity and CDKN2A expression were measured by reverse transcriptase (RT)–qPCR. Our results show that acute malaria infection affects cellular aging as reflected by elevated levels of CDKN2A expression, lower telomerase activity, and substantial telomere shortening during the first three months postinfection. After that CDKN2A expression declined, telomerase activity increased and telomere length was gradually restored over one year, reflecting that cellular aging was reversed. These findings demonstrate that malaria infection affects cellular aging and the underlying cellular mechanism by which pathogens can affect host cellular aging and longevity need to be elucidated. Our results urge the need to investigate whether repeated malaria infections have more pronounced and long-lasting effects on cellular aging and lifespan (similarly to what was observed in birds) in populations living in malaria endemic areas.
      PubDate: 2017-11-16T03:20:31.13157-05:0
      DOI: 10.1111/acel.12702
       
  • SIRT3 deregulation is linked to mitochondrial dysfunction in Alzheimer's
           disease

    • Authors: Junghee Lee; Yunha Kim, Tian Liu, Yu Jin Hwang, Seung Jae Hyeon, Hyeonjoo Im, Kyungeun Lee, Victor E. Alvarez, Ann C. McKee, Soo-Jong Um, Manwook Hur, Inhee Mook-Jung, Neil W. Kowall, Hoon Ryu
      Abstract: Alzheimer's disease (AD) is the leading cause of dementia in the elderly. Despite decades of study, effective treatments for AD are lacking. Mitochondrial dysfunction has been closely linked to the pathogenesis of AD, but the relationship between mitochondrial pathology and neuronal damage is poorly understood. Sirtuins (SIRT, silent mating type information regulation 2 homolog in yeast) are NAD-dependent histone deacetylases involved in aging and longevity. The objective of this study was to investigate the relationship between SIRT3 and mitochondrial function and neuronal activity in AD. SIRT3 mRNA and protein levels were significantly decreased in AD cerebral cortex, and Ac-p53 K320 was significantly increased in AD mitochondria. SIRT3 prevented p53-induced mitochondrial dysfunction and neuronal damage in a deacetylase activity-dependent manner. Notably, mitochondrially targeted p53 (mito-p53) directly reduced mitochondria DNA-encoded ND2 and ND4 gene expression resulting in increased reactive oxygen species (ROS) and reduced mitochondrial oxygen consumption. ND2 and ND4 gene expressions were significantly decreased in patients with AD. p53-ChIP analysis verified the presence of p53-binding elements in the human mitochondrial genome and increased p53 occupancy of mitochondrial DNA in AD. SIRT3 overexpression restored the expression of ND2 and ND4 and improved mitochondrial oxygen consumption by repressing mito-p53 activity. Our results indicate that SIRT3 dysfunction leads to p53-mediated mitochondrial and neuronal damage in AD. Therapeutic modulation of SIRT3 activity may ameliorate mitochondrial pathology and neurodegeneration in AD.
      PubDate: 2017-11-11T08:14:10.06929-05:0
      DOI: 10.1111/acel.12679
       
  • Running-wheel activity delays mitochondrial respiratory flux decline in
           aging mouse muscle via a post-transcriptional mechanism

    • Authors: Sarah Stolle; Jolita Ciapaite, Aaffien C. Reijne, Alzbeta Talarovicova, Justina C. Wolters, Raúl Aguirre-Gamboa, Pieter Vlies, Kim Lange, Pieter B. Neerincx, Gerben Vries, Patrick Deelen, Morris A. Swertz, Yang Li, Rainer Bischoff, Hjalmar P. Permentier, Peter L. Horvatovitch, Albert K. Groen, Gertjan Dijk, Dirk-Jan Reijngoud, Barbara M. Bakker
      Abstract: Loss of mitochondrial respiratory flux is a hallmark of skeletal muscle aging, contributing to a progressive decline of muscle strength. Endurance exercise alleviates the decrease in respiratory flux, both in humans and in rodents. Here, we dissect the underlying mechanism of mitochondrial flux decline by integrated analysis of the molecular network.Mice were given a lifelong ad libitum low-fat or high-fat sucrose diet and were further divided into sedentary and running-wheel groups. At 6, 12, 18 and 24 months, muscle weight, triglyceride content and mitochondrial respiratory flux were analysed. Subsequently, transcriptome was measured by RNA-Seq and proteome by targeted LC-MS/MS analysis with 13C-labelled standards. In the sedentary groups, mitochondrial respiratory flux declined with age. Voluntary running protected the mitochondrial respiratory flux until 18 months of age. Beyond this time point, all groups converged. Regulation Analysis of flux, proteome and transcriptome showed that the decline of flux was equally regulated at the proteomic and at the metabolic level, while regulation at the transcriptional level was marginal. Proteomic regulation was most prominent at the beginning and at the end of the pathway, namely at the pyruvate dehydrogenase complex and at the synthesis and transport of ATP. Further proteomic regulation was scattered across the entire pathway, revealing an effective multisite regulation. Finally, reactions regulated at the protein level were highly overlapping between the four experimental groups, suggesting a common, post-transcriptional mechanism of muscle aging.
      PubDate: 2017-11-09T05:15:34.802321-05:
      DOI: 10.1111/acel.12700
       
  • Ketone body 3-hydroxybutyrate mimics calorie restriction via the Nrf2
           activator, fumarate, in the retina

    • Authors: Yusuke Izuta; Toshihiro Imada, Ryuji Hisamura, Erina Oonishi, Shigeru Nakamura, Emi Inagaki, Masataka Ito, Tomoyoshi Soga, Kazuo Tsubota
      Abstract: Calorie restriction (CR) being the most robust dietary intervention provides various health benefits. D-3-hydroxybutyrate (3HB), a major physiological ketone, has been proposed as an important endogenous molecule for CR. To investigate the role of 3HB in CR, we investigated potential shared mechanisms underlying increased retinal 3HB induced by CR and exogenously applied 3HB without CR to protect against ischemic retinal degeneration. The repeated elevation of retinal 3HB, with or without CR, suppressed retinal degeneration. Metabolomic analysis showed that the antioxidant pentose phosphate pathway and its limiting enzyme, glucose-6-phosphate dehydrogenase (G6PD), were concomitantly preserved. Importantly, the upregulation of nuclear factor erythroid 2 p45-related factor 2 (Nrf2), a regulator of G6PD, and elevation of the tricarboxylic acid cycle's Nrf2 activator, fumarate, were also shared. Together, our findings suggest that CR provides retinal antioxidative defense by 3HB through the antioxidant Nrf2 pathway via modification of a tricarboxylic acid cycle intermediate during 3HB metabolism.
      PubDate: 2017-11-09T04:56:25.970457-05:
      DOI: 10.1111/acel.12699
       
  • Brain 5-lipoxygenase over-expression worsens memory, synaptic integrity,
           and tau pathology in the P301S mice

    • Authors: Alana N. Vagnozzi; Phillip F. Giannopoulos, Domenico Praticò
      Abstract: Progressive accumulation of highly phosphorylated tau protein isoforms is the main feature of a group of neurodegenerative diseases collectively called tauopathies. Data from human and animal models of these diseases have shown that neuroinflammation often accompanies their pathogenesis. The 5-lipoxygenase (5LO) is an enzyme widely expressed in the brain and a source of potent pro-inflammatory mediators, while its pharmacological inhibition modulates the phenotype of a tau transgenic mouse model, the htau mice. By employing an adeno-associated viral vector system to over-express 5LO in the brain, we examined its contribution to the behavioral deficits and neuropathology in a different transgenic mouse model of tauopathy, the P301S mouse line. Compared with controls, 5LO-targeted gene brain over-expression in these mice resulted in a worsening of behavioral and motor deficits. Over-expression of 5LO resulted in microglia and astrocyte activation and significant synaptic pathology, which was associated with a significant elevation of tau phosphorylation at specific epitopes, tau insoluble fraction, and activation of the cdk5 kinase. In vitro studies confirmed that 5LO directly modulates tau phosphorylation at the same epitopes via the cdk5 kinase pathway. These data demonstrate that 5LO plays a direct role in tau phosphorylation and is an active player in the development of the entire tau phenotype. They provide further support to the hypothesis that 5LO is a viable therapeutic target for the treatment and/or prevention of human tauopathy.
      PubDate: 2017-11-04T23:05:46.271017-05:
      DOI: 10.1111/acel.12695
       
  • Amyloid Beta monomers regulate cyclic adenosine monophosphate response
           element binding protein functions by activating type-1 insulin-like growth
           factor receptors in neuronal cells

    • Authors: Stefania Zimbone; Irene Monaco, Fiorenza Gianì, Giuseppe Pandini, Agata G. Copani, Maria Laura Giuffrida, Enrico Rizzarelli
      Abstract: Alzheimer's disease (AD) is a progressive neurodegenerative disorder associated with synaptic dysfunction, pathological accumulation of β-amyloid (Aβ), and neuronal loss. The self-association of Aβ monomers into soluble oligomers seems to be crucial for the development of neurotoxicity (J. Neurochem., 00, 2007 and 1172). Aβ oligomers have been suggested to compromise neuronal functions in AD by reducing the expression levels of the CREB target gene and brain-derived neurotrophic factor (BDNF) (J. Neurosci., 27, 2007 and 2628; Neurobiol. Aging, 36, 2015 and 20406 Mol. Neurodegener., 6, 2011 and 60). We previously reported a broad neuroprotective activity of physiological Aβ monomers, involving the activation of type-1 insulin-like growth factor receptors (IGF-IRs) (J. Neurosci., 29, 2009 and 10582, Front Cell Neurosci., 9, 2015 and 297). We now provide evidence that Aβ monomers, by activating the IGF-IR-stimulated PI3-K/AKT pathway, induce the activation of CREB in neurons and sustain BDNF transcription and release.
      PubDate: 2017-11-01T23:48:01.983088-05:
      DOI: 10.1111/acel.12684
       
  • Sirt2-BubR1 acetylation pathway mediates the effects of advanced maternal
           age on oocyte quality

    • Authors: Danhong Qiu; Xiaojing Hou, Longsen Han, Xiaoyan Li, Juan Ge, Qiang Wang
      Abstract: The level of Sirt2 protein is reduced in oocytes from aged mice, while exogenous expression of Sirt2 could ameliorate the maternal age-associated meiotic defects. To date, the underlying mechanism remains unclear. Here, we confirmed that specific depletion of Sirt2 disrupts maturational progression and spindle/chromosome organization in mouse oocytes, with compromised kinetochore–microtubule attachments. Candidate screening revealed that acetylation state of lysine 243 on BubR1 (BubR1-K243, an integral part of the spindle assembly checkpoint complex) functions during oocyte meiosis, and acetylation-mimetic mutant BubR1-K243Q results in the very similar phenotypes as Sirt2-knockdown oocytes. Furthermore, we found that nonacetylatable-mimetic mutant BubR1-K243R partly prevents the meiotic deficits in oocytes depleted of Sirt2. Importantly, BubR1-K243R overexpression in oocytes derived from aged mice markedly suppresses spindle/chromosome anomalies and thereupon lowers the incidence of aneuploid eggs. In sum, our data suggest that Sirt2-dependent BubR1 deacetylation involves in the regulation of meiotic apparatus in normal oocytes and mediates the effects of advanced maternal age on oocyte quality.
      PubDate: 2017-10-25T01:11:58.13439-05:0
      DOI: 10.1111/acel.12698
       
  • PGC-1α affects aging-related changes in muscle and motor function by
           modulating specific exercise-mediated changes in old mice

    • Authors: Jonathan F. Gill; Gesa Santos, Svenia Schnyder, Christoph Handschin
      Abstract: The age-related impairment in muscle function results in a drastic decline in motor coordination and mobility in elderly individuals. Regular physical activity is the only efficient intervention to prevent and treat this age-associated degeneration. However, the mechanisms that underlie the therapeutic effect of exercise in this context remain unclear. We assessed whether endurance exercise training in old age is sufficient to affect muscle and motor function. Moreover, as muscle peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) is a key regulatory hub in endurance exercise adaptation with decreased expression in old muscle, we studied the involvement of PGC-1α in the therapeutic effect of exercise in aging. Intriguingly, PGC-1α muscle-specific knockout and overexpression, respectively, precipitated and alleviated specific aspects of aging-related deterioration of muscle function in old mice, while other muscle dysfunctions remained unchanged upon PGC-1α modulation. Surprisingly, we discovered that muscle PGC-1α was not only involved in improving muscle endurance and mitochondrial remodeling, but also phenocopied endurance exercise training in advanced age by contributing to maintaining balance and motor coordination in old animals. Our data therefore suggest that the benefits of exercise, even when performed at old age, extend beyond skeletal muscle and are at least in part mediated by PGC-1α.
      PubDate: 2017-10-25T01:11:04.148806-05:
      DOI: 10.1111/acel.12697
       
  • Influence of cell distribution and diabetes status on the association
           between mitochondrial DNA copy number and aging phenotypes in the
           InCHIANTI study

    • Authors: Ann Zenobia Moore; Jun Ding, Marcus A. Tuke, Andrew R. Wood, Stefania Bandinelli, Timothy M. Frayling, Luigi Ferrucci
      Abstract: Mitochondrial DNA copy number (mtDNA-CN) estimated in whole blood is a novel marker of mitochondrial mass and function that can be used in large population-based studies. Analyses that attempt to relate mtDNA-CN to specific aging phenotypes may be confounded by differences in the distribution of blood cell types across samples. Also, low or high mtDNA-CN may have a different meaning given the presence of diseases associated with mitochondrial damage. We evaluated the impact of blood cell type distribution and diabetes status on the association between mtDNA-CN and aging phenotypes, namely chronologic age, interleukin-6, hemoglobin, and all-cause mortality, among 672 participants of the InCHIANTI study. After accounting for white blood cell count, platelet count, and white blood cell proportions in multivariate models, associations of mtDNA-CN with age and interleukin-6 were no longer statistically significant. Evaluation of a statistical interaction by diabetes status suggested heterogeneity of effects in the analysis of mortality (P 
      PubDate: 2017-10-19T00:45:19.598565-05:
      DOI: 10.1111/acel.12683
       
  • Enhanced inflammation and attenuated tumor suppressor pathways are
           associated with oncogene-induced lung tumors in aged mice

    • Authors: Neha Parikh; Ryan L. Shuck, Mihai Gagea, Lanlan Shen, Lawrence A. Donehower
      Abstract: Aging is often accompanied by a dramatic increase in cancer susceptibility. To gain insights into how aging affects tumor susceptibility, we generated a conditional mouse model in which oncogenic KrasG12D was activated specifically in lungs of young (3–5 months) and old (19–24 months) mice. Activation of KrasG12D in old mice resulted in shorter survival and development of higher-grade lung tumors. Six weeks after KrasG12D activation, old lung tissues contained higher numbers of adenomas than their young tissue counterparts. Lung tumors in old mice displayed higher proliferation rates, as well as attenuated DNA damage and p53 tumor suppressor responses. Gene expression comparison of lung tumors from young and old mice revealed upregulation of extracellular matrix-related genes in young tumors, indicative of a robust cancer-associated fibroblast response. In old tumors, numerous inflammation-related genes such as Ccl7, IL-1β, Cxcr6, and IL-15ra were consistently upregulated. Increased numbers of immune cells were localized around the periphery of lung adenomas from old mice. Our experiments indicate that more aggressive lung tumor formation in older KrasG12D mice may be in part the result of subdued tumor suppressor and DNA damage responses, an enhanced inflammatory milieu, and a more accommodating tissue microenvironment.
      PubDate: 2017-10-18T23:06:13.153748-05:
      DOI: 10.1111/acel.12691
       
  • Anti-inflammaging effects of human alpha-1 antitrypsin

    • Authors: Ye Yuan; Benedetto DiCiaccio, Ying Li, Ahmed S. Elshikha, Denis Titov, Brian Brenner, Lee Seifer, Hope Pan, Nurdina Karic, Mohammad A. Akbar, Yuanqing Lu, Sihong Song, Lei Zhou
      Abstract: Inflammaging plays an important role in most age-related diseases. However, the mechanism of inflammaging is largely unknown, and therapeutic control of inflammaging is challenging. Human alpha-1 antitrypsin (hAAT) has immune-regulatory, anti-inflammatory, and cytoprotective properties as demonstrated in several disease models including type 1 diabetes, arthritis, lupus, osteoporosis, and stroke. To test the potential anti-inflammaging effect of hAAT, we generated transgenic Drosophila lines expressing hAAT. Surprisingly, the lifespan of hAAT-expressing lines was significantly longer than that of genetically matched controls. To understand the mechanism underlying the anti-aging effect of hAAT, we monitored the expression of aging-associated genes and found that aging-induced expressions of Relish (NF-ĸB orthologue) and Diptericin were significantly lower in hAAT lines than in control lines. RNA-seq analysis revealed that innate immunity genes regulated by NF-kB were significantly and specifically inhibited in hAAT transgenic Drosophila lines. To confirm this anti-inflammaging effect in human cells, we treated X-ray-induced senescence cells with hAAT and showed that hAAT treatment significantly decreased the expression and maturation of IL-6 and IL-8, two major factors of senescence-associated secretory phenotype. Consistent with results from Drosophila,RNA-seq analysis also showed that hAAT treatment significantly inhibited inflammation related genes and pathways. Together, our results demonstrated that hAAT significantly inhibited inflammaging in both Drosophila and human cell models. As hAAT is a FDA-approved drug with a confirmed safety profile, this novel therapeutic potential may make hAAT a promising candidate to combat aging and aging-related diseases.
      PubDate: 2017-10-17T03:57:00.24757-05:0
      DOI: 10.1111/acel.12694
       
  • Human CD8+ EMRA T cells display a senescence-associated secretory
           phenotype regulated by p38 MAPK

    • Authors: Lauren A. Callender; Elizabeth C. Carroll, Robert W. J. Beal, Emma S. Chambers, Sussan Nourshargh, Arne N. Akbar, Sian M. Henson
      Abstract: Cellular senescence is accompanied by a senescence-associated secretory phenotype (SASP). We show here that primary human senescent CD8+ T cells also display a SASP comprising chemokines, cytokines and extracellular matrix remodelling proteases that are unique to this subset and contribute to age-associated inflammation. We found the CD8+ CD45RA+CD27− EMRA subset to be the most heterogeneous, with a population aligning with the naïve T cells and another with a closer association to the effector memory subset. However, despite the differing processes that give rise to these senescent CD8+ T cells once generated, they both adopt a unique secretory profile with no commonality to any other subset, aligning more closely with senescence than quiescence. Furthermore, we also show that the SASP observed in senescent CD8+ T cells is governed by p38 MAPK signalling.
      PubDate: 2017-10-12T01:40:59.179802-05:
      DOI: 10.1111/acel.12675
       
  • Interplay of pathogenic forms of human tau with different autophagic
           pathways

    • Authors: Benjamin Caballero; Yipeng Wang, Antonio Diaz, Inmaculada Tasset, Yves Robert Juste, Eva-Maria Mandelkow, Eckhard Mandelkow, Ana Maria Cuervo
      Abstract: Loss of neuronal proteostasis, a common feature of the aging brain, is accelerated in neurodegenerative disorders, including different types of tauopathies. Aberrant turnover of tau, a microtubule-stabilizing protein, contributes to its accumulation and subsequent toxicity in tauopathy patients’ brains. A direct toxic effect of pathogenic forms of tau on the proteolytic systems that normally contribute to their turnover has been proposed. In this study, we analyzed the contribution of three different types of autophagy, macroautophagy, chaperone-mediated autophagy, and endosomal microautophagy to the degradation of tau protein variants and tau mutations associated with this age-related disease. We have found that the pathogenic P301L mutation inhibits degradation of tau by any of the three autophagic pathways, whereas the risk-associated tau mutation A152T reroutes tau for degradation through a different autophagy pathway. We also found defective autophagic degradation of tau when using mutations that mimic common posttranslational modifications in tau or known to promote its aggregation. Interestingly, although most mutations markedly reduced degradation of tau through autophagy, the step of this process preferentially affected varies depending on the type of tau mutation. Overall, our studies unveil a complex interplay between the multiple modifications of tau and selective forms of autophagy that may determine its physiological degradation and its faulty clearance in the disease context.
      PubDate: 2017-10-12T01:36:09.073264-05:
      DOI: 10.1111/acel.12692
       
  • Ghrelin deletion protects against age-associated hepatic steatosis by
           downregulating the C/EBPα-p300/DGAT1 pathway

    • Authors: Bobby Guillory; Nicole Jawanmardi, Polina Iakova, Barbara Anderson, Pu Zang, Nikolai A. Timchenko, Jose M. Garcia
      Abstract: Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease worldwide. NAFLD usually begins as low-grade hepatic steatosis which further progresses in an age-dependent manner to nonalcoholic steatohepatitis (NASH), fibrosis, cirrhosis, and hepatocellular carcinoma in some patients. Ghrelin is a hormone known to promote adiposity in rodents and humans, but its potential role in hepatic steatosis is unknown. We hypothesized that genetic ghrelin deletion will protect against the development of age-related hepatic steatosis. To examine this hypothesis, we utilized ghrelin knockout (KO) mice. Although no different in young animals (3 months old), we found that at 20 months of age, ghrelin KO mice have significantly reduced hepatic steatosis compared to aged-matched wild-type (WT) mice. Examination of molecular pathways by which deletion of ghrelin reduces steatosis showed that the increase in expression of diacylglycerol O-acyltransferase-1 (DGAT1), one of the key enzymes of triglyceride (TG) synthesis, seen with age in WT mice, is not present in KO mice. This was due to the lack of activation of CCAAT/enhancer binding protein-alpha (C/EBPα) protein and subsequent reduction of C/EBPα-p300 complexes. These complexes were abundant in livers of old WT mice and were bound to and activated the DGAT1 promoter. However, the C/EBPα-p300 complexes were not detected on the DGAT1 promoter in livers of old KO mice resulting in lower levels of the enzyme. In conclusion, these studies demonstrate the mechanism by which ghrelin deletion prevents age-associated hepatic steatosis and suggest that targeting this pathway may offer therapeutic benefit for NAFLD.
      PubDate: 2017-10-12T01:35:38.679579-05:
      DOI: 10.1111/acel.12688
       
 
 
JournalTOCs
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Email: journaltocs@hw.ac.uk
Tel: +00 44 (0)131 4513762
Fax: +00 44 (0)131 4513327
 
Home (Search)
Subjects A-Z
Publishers A-Z
Customise
APIs
Your IP address: 54.235.57.105
 
About JournalTOCs
API
Help
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-