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Publisher: Springer-Verlag (Total: 2348 journals)

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Showing 1 - 200 of 2348 Journals sorted alphabetically
3D Printing in Medicine     Open Access   (Followers: 1)
3D Research     Hybrid Journal   (Followers: 21, SJR: 0.222, CiteScore: 1)
4OR: A Quarterly J. of Operations Research     Hybrid Journal   (Followers: 10, SJR: 0.825, CiteScore: 1)
AAPS J.     Hybrid Journal   (Followers: 22, SJR: 1.118, CiteScore: 4)
AAPS PharmSciTech     Hybrid Journal   (Followers: 7, SJR: 0.752, CiteScore: 3)
Abdominal Imaging     Hybrid Journal   (Followers: 15, SJR: 0.866, CiteScore: 2)
Abhandlungen aus dem Mathematischen Seminar der Universitat Hamburg     Hybrid Journal   (Followers: 4, SJR: 0.439, CiteScore: 0)
Academic Psychiatry     Full-text available via subscription   (Followers: 24, SJR: 0.53, CiteScore: 1)
Academic Questions     Hybrid Journal   (Followers: 8, SJR: 0.106, CiteScore: 0)
Accreditation and Quality Assurance: J. for Quality, Comparability and Reliability in Chemical Measurement     Hybrid Journal   (Followers: 26, SJR: 0.316, CiteScore: 1)
Acoustical Physics     Hybrid Journal   (Followers: 11, SJR: 0.359, CiteScore: 1)
Acoustics Australia     Hybrid Journal   (SJR: 0.232, CiteScore: 1)
Acta Analytica     Hybrid Journal   (Followers: 7, SJR: 0.367, CiteScore: 0)
Acta Applicandae Mathematicae     Hybrid Journal   (Followers: 1, SJR: 0.675, CiteScore: 1)
Acta Biotheoretica     Hybrid Journal   (Followers: 4, SJR: 0.284, CiteScore: 1)
Acta Diabetologica     Hybrid Journal   (Followers: 18, SJR: 1.587, CiteScore: 3)
Acta Endoscopica     Hybrid Journal   (Followers: 1)
acta ethologica     Hybrid Journal   (Followers: 4, SJR: 0.769, CiteScore: 1)
Acta Geochimica     Hybrid Journal   (Followers: 6, SJR: 0.24, CiteScore: 1)
Acta Geodaetica et Geophysica     Hybrid Journal   (Followers: 2, SJR: 0.305, CiteScore: 1)
Acta Geophysica     Hybrid Journal   (Followers: 10, SJR: 0.312, CiteScore: 1)
Acta Geotechnica     Hybrid Journal   (Followers: 7, SJR: 1.588, CiteScore: 3)
Acta Informatica     Hybrid Journal   (Followers: 5, SJR: 0.517, CiteScore: 1)
Acta Mathematica     Hybrid Journal   (Followers: 12, SJR: 7.066, CiteScore: 3)
Acta Mathematica Hungarica     Hybrid Journal   (Followers: 2, SJR: 0.452, CiteScore: 1)
Acta Mathematica Sinica, English Series     Hybrid Journal   (Followers: 6, SJR: 0.379, CiteScore: 1)
Acta Mathematica Vietnamica     Hybrid Journal   (SJR: 0.27, CiteScore: 0)
Acta Mathematicae Applicatae Sinica, English Series     Hybrid Journal   (SJR: 0.208, CiteScore: 0)
Acta Mechanica     Hybrid Journal   (Followers: 21, SJR: 1.04, CiteScore: 2)
Acta Mechanica Sinica     Hybrid Journal   (Followers: 5, SJR: 0.607, CiteScore: 2)
Acta Metallurgica Sinica (English Letters)     Hybrid Journal   (Followers: 7, SJR: 0.576, CiteScore: 2)
Acta Meteorologica Sinica     Hybrid Journal   (Followers: 3, SJR: 0.638, CiteScore: 1)
Acta Neurochirurgica     Hybrid Journal   (Followers: 6, SJR: 0.822, CiteScore: 2)
Acta Neurologica Belgica     Hybrid Journal   (Followers: 1, SJR: 0.376, CiteScore: 1)
Acta Neuropathologica     Hybrid Journal   (Followers: 5, SJR: 7.589, CiteScore: 12)
Acta Oceanologica Sinica     Hybrid Journal   (Followers: 3, SJR: 0.334, CiteScore: 1)
Acta Physiologiae Plantarum     Hybrid Journal   (Followers: 2, SJR: 0.574, CiteScore: 2)
Acta Politica     Hybrid Journal   (Followers: 14, SJR: 0.605, CiteScore: 1)
Activitas Nervosa Superior     Hybrid Journal   (SJR: 0.147, CiteScore: 0)
adhäsion KLEBEN & DICHTEN     Hybrid Journal   (Followers: 7, SJR: 0.103, CiteScore: 0)
ADHD Attention Deficit and Hyperactivity Disorders     Hybrid Journal   (Followers: 23, SJR: 0.72, CiteScore: 2)
Adhesion Adhesives & Sealants     Hybrid Journal   (Followers: 9)
Administration and Policy in Mental Health and Mental Health Services Research     Partially Free   (Followers: 16, SJR: 1.005, CiteScore: 2)
Adsorption     Hybrid Journal   (Followers: 4, SJR: 0.703, CiteScore: 2)
Advances in Applied Clifford Algebras     Hybrid Journal   (Followers: 4, SJR: 0.698, CiteScore: 1)
Advances in Atmospheric Sciences     Hybrid Journal   (Followers: 37, SJR: 0.956, CiteScore: 2)
Advances in Computational Mathematics     Hybrid Journal   (Followers: 19, SJR: 0.812, CiteScore: 1)
Advances in Contraception     Hybrid Journal   (Followers: 3)
Advances in Data Analysis and Classification     Hybrid Journal   (Followers: 52, SJR: 1.09, CiteScore: 1)
Advances in Gerontology     Partially Free   (Followers: 8, SJR: 0.144, CiteScore: 0)
Advances in Health Sciences Education     Hybrid Journal   (Followers: 28, SJR: 1.64, CiteScore: 2)
Advances in Manufacturing     Hybrid Journal   (Followers: 3, SJR: 0.475, CiteScore: 2)
Advances in Polymer Science     Hybrid Journal   (Followers: 44, SJR: 1.04, CiteScore: 3)
Advances in Therapy     Hybrid Journal   (Followers: 5, SJR: 1.075, CiteScore: 3)
Aegean Review of the Law of the Sea and Maritime Law     Hybrid Journal   (Followers: 6)
Aequationes Mathematicae     Hybrid Journal   (Followers: 2, SJR: 0.517, CiteScore: 1)
Aerobiologia     Hybrid Journal   (Followers: 3, SJR: 0.673, CiteScore: 2)
Aesthetic Plastic Surgery     Hybrid Journal   (Followers: 9, SJR: 0.825, CiteScore: 1)
African Archaeological Review     Hybrid Journal   (Followers: 16, SJR: 0.862, CiteScore: 1)
Afrika Matematika     Hybrid Journal   (Followers: 1, SJR: 0.235, CiteScore: 0)
AGE     Hybrid Journal   (Followers: 7)
Ageing Intl.     Hybrid Journal   (Followers: 7, SJR: 0.39, CiteScore: 1)
Aggiornamenti CIO     Hybrid Journal   (Followers: 1)
Aging Clinical and Experimental Research     Hybrid Journal   (Followers: 3, SJR: 0.67, CiteScore: 2)
Agricultural Research     Hybrid Journal   (Followers: 5, SJR: 0.276, CiteScore: 1)
Agriculture and Human Values     Hybrid Journal   (Followers: 14, SJR: 1.173, CiteScore: 3)
Agroforestry Systems     Hybrid Journal   (Followers: 20, SJR: 0.663, CiteScore: 1)
Agronomy for Sustainable Development     Hybrid Journal   (Followers: 12, SJR: 1.864, CiteScore: 6)
AI & Society     Hybrid Journal   (Followers: 8, SJR: 0.227, CiteScore: 1)
AIDS and Behavior     Hybrid Journal   (Followers: 14, SJR: 1.792, CiteScore: 3)
Air Quality, Atmosphere & Health     Hybrid Journal   (Followers: 4, SJR: 0.862, CiteScore: 3)
Akupunktur & Aurikulomedizin     Full-text available via subscription   (Followers: 1)
Algebra and Logic     Hybrid Journal   (Followers: 6, SJR: 0.531, CiteScore: 0)
Algebra Universalis     Hybrid Journal   (Followers: 2, SJR: 0.583, CiteScore: 1)
Algebras and Representation Theory     Hybrid Journal   (Followers: 1, SJR: 1.095, CiteScore: 1)
Algorithmica     Hybrid Journal   (Followers: 9, SJR: 0.56, CiteScore: 1)
Allergo J.     Full-text available via subscription   (Followers: 1, SJR: 0.234, CiteScore: 0)
Allergo J. Intl.     Hybrid Journal   (Followers: 2)
Alpine Botany     Hybrid Journal   (Followers: 5, SJR: 1.11, CiteScore: 3)
ALTEX : Alternatives to Animal Experimentation     Open Access   (Followers: 3)
AMBIO     Hybrid Journal   (Followers: 10, SJR: 1.569, CiteScore: 4)
American J. of Cardiovascular Drugs     Hybrid Journal   (Followers: 16, SJR: 0.951, CiteScore: 3)
American J. of Community Psychology     Hybrid Journal   (Followers: 28, SJR: 1.329, CiteScore: 2)
American J. of Criminal Justice     Hybrid Journal   (Followers: 7, SJR: 0.772, CiteScore: 1)
American J. of Cultural Sociology     Hybrid Journal   (Followers: 16, SJR: 0.46, CiteScore: 1)
American J. of Dance Therapy     Hybrid Journal   (Followers: 4, SJR: 0.181, CiteScore: 0)
American J. of Potato Research     Hybrid Journal   (Followers: 2, SJR: 0.611, CiteScore: 1)
American J. of Psychoanalysis     Hybrid Journal   (Followers: 21, SJR: 0.314, CiteScore: 0)
American Sociologist     Hybrid Journal   (Followers: 12, SJR: 0.35, CiteScore: 0)
Amino Acids     Hybrid Journal   (Followers: 8, SJR: 1.135, CiteScore: 3)
AMS Review     Partially Free   (Followers: 4)
Analog Integrated Circuits and Signal Processing     Hybrid Journal   (Followers: 7, SJR: 0.211, CiteScore: 1)
Analysis and Mathematical Physics     Hybrid Journal   (Followers: 5, SJR: 0.536, CiteScore: 1)
Analysis in Theory and Applications     Hybrid Journal   (Followers: 1)
Analysis of Verbal Behavior     Hybrid Journal   (Followers: 5)
Analytical and Bioanalytical Chemistry     Hybrid Journal   (Followers: 32, SJR: 0.978, CiteScore: 3)
Anatomical Science Intl.     Hybrid Journal   (Followers: 2, SJR: 0.367, CiteScore: 1)
Angewandte Schmerztherapie und Palliativmedizin     Hybrid Journal  
Angiogenesis     Hybrid Journal   (Followers: 3, SJR: 2.177, CiteScore: 5)
Animal Cognition     Hybrid Journal   (Followers: 19, SJR: 1.389, CiteScore: 3)
Annales françaises de médecine d'urgence     Hybrid Journal   (Followers: 1, SJR: 0.192, CiteScore: 0)
Annales Henri Poincaré     Hybrid Journal   (Followers: 3, SJR: 1.097, CiteScore: 2)
Annales mathématiques du Québec     Hybrid Journal   (Followers: 4, SJR: 0.438, CiteScore: 0)
Annali dell'Universita di Ferrara     Hybrid Journal   (SJR: 0.429, CiteScore: 0)
Annali di Matematica Pura ed Applicata     Hybrid Journal   (Followers: 1, SJR: 1.197, CiteScore: 1)
Annals of Biomedical Engineering     Hybrid Journal   (Followers: 18, SJR: 1.042, CiteScore: 3)
Annals of Combinatorics     Hybrid Journal   (Followers: 4, SJR: 0.932, CiteScore: 1)
Annals of Data Science     Hybrid Journal   (Followers: 12)
Annals of Dyslexia     Hybrid Journal   (Followers: 10, SJR: 0.85, CiteScore: 2)
Annals of Finance     Hybrid Journal   (Followers: 30, SJR: 0.579, CiteScore: 1)
Annals of Forest Science     Hybrid Journal   (Followers: 7, SJR: 0.986, CiteScore: 2)
Annals of Global Analysis and Geometry     Hybrid Journal   (Followers: 1, SJR: 1.228, CiteScore: 1)
Annals of Hematology     Hybrid Journal   (Followers: 15, SJR: 1.043, CiteScore: 2)
Annals of Mathematics and Artificial Intelligence     Hybrid Journal   (Followers: 12, SJR: 0.413, CiteScore: 1)
Annals of Microbiology     Hybrid Journal   (Followers: 11, SJR: 0.479, CiteScore: 2)
Annals of Nuclear Medicine     Hybrid Journal   (Followers: 4, SJR: 0.687, CiteScore: 2)
Annals of Operations Research     Hybrid Journal   (Followers: 10, SJR: 0.943, CiteScore: 2)
Annals of Ophthalmology     Hybrid Journal   (Followers: 11)
Annals of Regional Science     Hybrid Journal   (Followers: 7, SJR: 0.614, CiteScore: 1)
Annals of Software Engineering     Hybrid Journal   (Followers: 13)
Annals of Solid and Structural Mechanics     Hybrid Journal   (Followers: 9, SJR: 0.239, CiteScore: 1)
Annals of Surgical Oncology     Hybrid Journal   (Followers: 13, SJR: 1.986, CiteScore: 4)
Annals of Telecommunications     Hybrid Journal   (Followers: 9, SJR: 0.223, CiteScore: 1)
Annals of the Institute of Statistical Mathematics     Hybrid Journal   (Followers: 1, SJR: 1.495, CiteScore: 1)
Antonie van Leeuwenhoek     Hybrid Journal   (Followers: 5, SJR: 0.834, CiteScore: 2)
Apidologie     Hybrid Journal   (Followers: 4, SJR: 1.22, CiteScore: 3)
APOPTOSIS     Hybrid Journal   (Followers: 8, SJR: 1.424, CiteScore: 4)
Applicable Algebra in Engineering, Communication and Computing     Hybrid Journal   (Followers: 2, SJR: 0.294, CiteScore: 1)
Applications of Mathematics     Hybrid Journal   (Followers: 2, SJR: 0.602, CiteScore: 1)
Applied Biochemistry and Biotechnology     Hybrid Journal   (Followers: 43, SJR: 0.571, CiteScore: 2)
Applied Biochemistry and Microbiology     Hybrid Journal   (Followers: 17, SJR: 0.21, CiteScore: 1)
Applied Cancer Research     Open Access  
Applied Categorical Structures     Hybrid Journal   (Followers: 2, SJR: 0.49, CiteScore: 0)
Applied Composite Materials     Hybrid Journal   (Followers: 49, SJR: 0.58, CiteScore: 2)
Applied Entomology and Zoology     Partially Free   (Followers: 4, SJR: 0.422, CiteScore: 1)
Applied Geomatics     Hybrid Journal   (Followers: 3, SJR: 0.733, CiteScore: 3)
Applied Geophysics     Hybrid Journal   (Followers: 8, SJR: 0.488, CiteScore: 1)
Applied Intelligence     Hybrid Journal   (Followers: 12, SJR: 0.6, CiteScore: 2)
Applied Magnetic Resonance     Hybrid Journal   (Followers: 4, SJR: 0.319, CiteScore: 1)
Applied Mathematics & Optimization     Hybrid Journal   (Followers: 6, SJR: 0.886, CiteScore: 1)
Applied Mathematics - A J. of Chinese Universities     Hybrid Journal   (SJR: 0.17, CiteScore: 0)
Applied Mathematics and Mechanics     Hybrid Journal   (Followers: 5, SJR: 0.461, CiteScore: 1)
Applied Microbiology and Biotechnology     Hybrid Journal   (Followers: 64, SJR: 1.182, CiteScore: 4)
Applied Physics A     Hybrid Journal   (Followers: 9, SJR: 0.481, CiteScore: 2)
Applied Physics B: Lasers and Optics     Hybrid Journal   (Followers: 24, SJR: 0.74, CiteScore: 2)
Applied Psychophysiology and Biofeedback     Hybrid Journal   (Followers: 8, SJR: 0.519, CiteScore: 2)
Applied Research in Quality of Life     Hybrid Journal   (Followers: 12, SJR: 0.316, CiteScore: 1)
Applied Solar Energy     Hybrid Journal   (Followers: 18, SJR: 0.225, CiteScore: 0)
Applied Spatial Analysis and Policy     Hybrid Journal   (Followers: 5, SJR: 0.542, CiteScore: 1)
Aquaculture Intl.     Hybrid Journal   (Followers: 23, SJR: 0.591, CiteScore: 2)
Aquarium Sciences and Conservation     Hybrid Journal   (Followers: 1)
Aquatic Ecology     Hybrid Journal   (Followers: 34, SJR: 0.656, CiteScore: 2)
Aquatic Geochemistry     Hybrid Journal   (Followers: 4, SJR: 0.591, CiteScore: 1)
Aquatic Sciences     Hybrid Journal   (Followers: 13, SJR: 1.109, CiteScore: 3)
Arabian J. for Science and Engineering     Hybrid Journal   (Followers: 5, SJR: 0.303, CiteScore: 1)
Arabian J. of Geosciences     Hybrid Journal   (Followers: 2, SJR: 0.319, CiteScore: 1)
Archaeological and Anthropological Sciences     Hybrid Journal   (Followers: 20, SJR: 1.052, CiteScore: 2)
Archaeologies     Hybrid Journal   (Followers: 12, SJR: 0.224, CiteScore: 0)
Archiv der Mathematik     Hybrid Journal   (Followers: 1, SJR: 0.725, CiteScore: 1)
Archival Science     Hybrid Journal   (Followers: 60, SJR: 0.745, CiteScore: 2)
Archive for History of Exact Sciences     Hybrid Journal   (Followers: 7, SJR: 0.186, CiteScore: 1)
Archive for Mathematical Logic     Hybrid Journal   (Followers: 3, SJR: 0.909, CiteScore: 1)
Archive for Rational Mechanics and Analysis     Hybrid Journal   (SJR: 3.93, CiteScore: 3)
Archive of Applied Mechanics     Hybrid Journal   (Followers: 5, SJR: 0.79, CiteScore: 2)
Archives and Museum Informatics     Hybrid Journal   (Followers: 142, SJR: 0.101, CiteScore: 0)
Archives of Computational Methods in Engineering     Hybrid Journal   (Followers: 5, SJR: 1.41, CiteScore: 5)
Archives of Dermatological Research     Hybrid Journal   (Followers: 7, SJR: 1.006, CiteScore: 2)
Archives of Environmental Contamination and Toxicology     Hybrid Journal   (Followers: 14, SJR: 0.773, CiteScore: 2)
Archives of Gynecology and Obstetrics     Hybrid Journal   (Followers: 16, SJR: 0.956, CiteScore: 2)
Archives of Microbiology     Hybrid Journal   (Followers: 8, SJR: 0.644, CiteScore: 2)
Archives of Orthopaedic and Trauma Surgery     Hybrid Journal   (Followers: 8, SJR: 1.146, CiteScore: 2)
Archives of Osteoporosis     Hybrid Journal   (Followers: 2, SJR: 0.71, CiteScore: 2)
Archives of Sexual Behavior     Hybrid Journal   (Followers: 10, SJR: 1.493, CiteScore: 3)
Archives of Toxicology     Hybrid Journal   (Followers: 17, SJR: 1.541, CiteScore: 5)
Archives of Virology     Hybrid Journal   (Followers: 5, SJR: 0.973, CiteScore: 2)
Archives of Women's Mental Health     Hybrid Journal   (Followers: 14, SJR: 1.274, CiteScore: 3)
Archivio di Ortopedia e Reumatologia     Hybrid Journal  
Archivum Immunologiae et Therapiae Experimentalis     Hybrid Journal   (Followers: 2, SJR: 0.946, CiteScore: 3)
ArgoSpine News & J.     Hybrid Journal  
Argumentation     Hybrid Journal   (Followers: 5, SJR: 0.349, CiteScore: 1)
Arid Ecosystems     Hybrid Journal   (Followers: 2, SJR: 0.2, CiteScore: 0)
Arkiv för Matematik     Hybrid Journal   (Followers: 1, SJR: 0.766, CiteScore: 1)
Arnold Mathematical J.     Hybrid Journal   (Followers: 1, SJR: 0.355, CiteScore: 0)
Arthropod-Plant Interactions     Hybrid Journal   (Followers: 2, SJR: 0.839, CiteScore: 2)
Arthroskopie     Hybrid Journal   (Followers: 1, SJR: 0.131, CiteScore: 0)
Artificial Intelligence and Law     Hybrid Journal   (Followers: 11, SJR: 0.937, CiteScore: 2)
Artificial Intelligence Review     Hybrid Journal   (Followers: 15, SJR: 0.833, CiteScore: 4)
Artificial Life and Robotics     Hybrid Journal   (Followers: 9, SJR: 0.226, CiteScore: 0)
Asia Europe J.     Hybrid Journal   (Followers: 5, SJR: 0.504, CiteScore: 1)
Asia Pacific Education Review     Hybrid Journal   (Followers: 12, SJR: 0.479, CiteScore: 1)
Asia Pacific J. of Management     Hybrid Journal   (Followers: 16, SJR: 1.185, CiteScore: 2)
Asia-Pacific Education Researcher     Hybrid Journal   (Followers: 12, SJR: 0.353, CiteScore: 1)
Asia-Pacific Financial Markets     Hybrid Journal   (Followers: 2, SJR: 0.187, CiteScore: 0)
Asia-Pacific J. of Atmospheric Sciences     Hybrid Journal   (Followers: 19, SJR: 0.855, CiteScore: 1)
Asian Business & Management     Hybrid Journal   (Followers: 9, SJR: 0.378, CiteScore: 1)
Asian J. of Business Ethics     Hybrid Journal   (Followers: 9)
Asian J. of Criminology     Hybrid Journal   (Followers: 5, SJR: 0.543, CiteScore: 1)
AStA Advances in Statistical Analysis     Hybrid Journal   (Followers: 3, SJR: 0.548, CiteScore: 1)
AStA Wirtschafts- und Sozialstatistisches Archiv     Hybrid Journal   (Followers: 5, SJR: 0.183, CiteScore: 0)
ästhetische dermatologie & kosmetologie     Full-text available via subscription  

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Journal Cover
Archives of Toxicology
Journal Prestige (SJR): 1.541
Citation Impact (citeScore): 5
Number of Followers: 17  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 1432-0738 - ISSN (Online) 0340-5761
Published by Springer-Verlag Homepage  [2348 journals]
  • Highlight report: quality control of stem cell-derived hepatocytes
    • Authors: Daniela Fernanda González Leiva
      Pages: 2409 - 2410
      PubDate: 2018-08-01
      DOI: 10.1007/s00204-018-2253-5
      Issue No: Vol. 92, No. 8 (2018)
       
  • Xenobiotica-metabolizing enzymes in the skin of rat, mouse, pig, guinea
           pig, man, and in human skin models
    • Authors: F. Oesch; E. Fabian; Robert Landsiedel
      Pages: 2411 - 2456
      Abstract: Studies on the metabolic fate of medical drugs, skin care products, cosmetics and other chemicals intentionally or accidently applied to the human skin have become increasingly important in order to ascertain pharmacological effectiveness and to avoid toxicities. The use of freshly excised human skin for experimental investigations meets with ethical and practical limitations. Hence information on xenobiotic-metabolizing enzymes (XME) in the experimental systems available for pertinent studies compared with native human skin has become crucial. This review collects available information of which—taken with great caution because of the still very limited data—the most salient points are: in the skin of all animal species and skin-derived in vitro systems considered in this review cytochrome P450 (CYP)-dependent monooxygenase activities (largely responsible for initiating xenobiotica metabolism in the organ which provides most of the xenobiotica metabolism of the mammalian organism, the liver) are very low to undetectable. Quite likely other oxidative enzymes [e.g. flavin monooxygenase, COX (cooxidation by prostaglandin synthase)] will turn out to be much more important for the oxidative xenobiotic metabolism in the skin. Moreover, conjugating enzyme activities such as glutathione transferases and glucuronosyltransferases are much higher than the oxidative CYP activities. Since these conjugating enzymes are predominantly detoxifying, the skin appears to be predominantly protected against CYP-generated reactive metabolites. The following recommendations for the use of experimental animal species or human skin in vitro models may tentatively be derived from the information available to date: for dermal absorption and for skin irritation esterase activity is of special importance which in pig skin, some human cell lines and reconstructed skin models appears reasonably close to native human skin. With respect to genotoxicity and sensitization reactive-metabolite-reducing XME in primary human keratinocytes and several reconstructed human skin models appear reasonably close to human skin. For a more detailed delineation and discussion of the severe limitations see the Conclusions section in the end of this review.
      PubDate: 2018-08-01
      DOI: 10.1007/s00204-018-2232-x
      Issue No: Vol. 92, No. 8 (2018)
       
  • Birth weights of newborns and pregnancy outcomes of environmentally
           boron-exposed females in Turkey
    • Authors: Yalçın Duydu; Nurşen Başaran; Aylin Üstündağ; Sevtap Aydın; Can Özgür Yalçın; Hatice Gül Anlar; Merve Bacanlı; Kaan Aydos; Cem Somer Atabekoğlu; Klaus Golka; Katja Ickstadt; Tanja Schwerdtle; Matthias Werner; Sören Meyer; Hermann M. Bolt
      Pages: 2475 - 2485
      Abstract: Boric acid and sodium borates are currently classified as being toxic to reproduction under “Category 1B” with the hazard statement of “H360 FD” in the European CLP regulation. This has prompted studies on boron-mediated reprotoxic effects in male workers in boron mining areas and boric acid production plants. By contrast, studies on boron-mediated developmental effects in females are scarce. The present study was designed to fill this gap. Hundred and ninety nine females residing in Bandirma and Bigadic participated in this study investigating pregnancy outcomes. The participants constituted a study group covering blood boron from low (< 100 ng B/g blood, n = 143) to high (> 150 ng B/g blood, n = 27) concentrations. The mean blood boron concentration and the mean estimated daily boron exposure of the high exposure group was 274.58 (151.81–975.66) ng B/g blood and 24.67 (10.47–57.86) mg B/day, respectively. In spite of the high level of daily boron exposure, boron-mediated adverse effects on induced abortion, spontaneous abortion (miscarriage), stillbirth, infant death, neonatal death, early neonatal death, preterm birth, congenital anomalies, sex ratio and birth weight of newborns were not observed.
      PubDate: 2018-08-01
      DOI: 10.1007/s00204-018-2238-4
      Issue No: Vol. 92, No. 8 (2018)
       
  • Integrated transcriptomics and metabolomics reveal signatures of lipid
           metabolism dysregulation in HepaRG liver cells exposed to PCB 126
    • Authors: Robin Mesnage; Martina Biserni; Sucharitha Balu; Clément Frainay; Nathalie Poupin; Fabien Jourdan; Eva Wozniak; Theodoros Xenakis; Charles A. Mein; Michael N. Antoniou
      Pages: 2533 - 2547
      Abstract: Chemical pollutant exposure is a risk factor contributing to the growing epidemic of non-alcoholic fatty liver disease (NAFLD) affecting human populations that consume a western diet. Although it is recognized that intoxication by chemical pollutants can lead to NAFLD, there is limited information available regarding the mechanism by which typical environmental levels of exposure can contribute to the onset of this disease. Here, we describe the alterations in gene expression profiles and metabolite levels in the human HepaRG liver cell line, a validated model for cellular steatosis, exposed to the polychlorinated biphenyl (PCB) 126, one of the most potent chemical pollutants that can induce NAFLD. Sparse partial least squares classification of the molecular profiles revealed that exposure to PCB 126 provoked a decrease in polyunsaturated fatty acids as well as an increase in sphingolipid levels, concomitant with a decrease in the activity of genes involved in lipid metabolism. This was associated with an increased oxidative stress reflected by marked disturbances in taurine metabolism. A gene ontology analysis showed hallmarks of an activation of the AhR receptor by dioxin-like compounds. These changes in metabolome and transcriptome profiles were observed even at the lowest concentration (100 pM) of PCB 126 tested. A decrease in docosatrienoate levels was the most sensitive biomarker. Overall, our integrated multi-omics analysis provides mechanistic insight into how this class of chemical pollutant can cause NAFLD. Our study lays the foundation for the development of molecular signatures of toxic effects of chemicals causing fatty liver diseases to move away from a chemical risk assessment based on in vivo animal experiments.
      PubDate: 2018-08-01
      DOI: 10.1007/s00204-018-2235-7
      Issue No: Vol. 92, No. 8 (2018)
       
  • Hepatocyte SHP deficiency protects mice from acetaminophen-evoked liver
           injury in a JNK-signaling regulation and GADD45β-dependent manner
    • Authors: Yong-Hoon Kim; Jung-Ran Noh; Jung Hwan Hwang; Kyoung-Shim Kim; Dong-Hee Choi; Jae-Hoon Kim; Sung Je Moon; Ji Hyun Choi; Yann Hérault; Tae Geol Lee; Hueng-Sik Choi; Chul-Ho Lee
      Pages: 2563 - 2572
      Abstract: Acetaminophen (APAP) overdose is a leading cause of drug-induced acute liver failure. Prolonged c-Jun N-terminal kinase (JNK) activation plays a central role in APAP-induced liver injury; however, growth arrest and DNA damage-inducible 45 beta (GADD45β) is known to inhibit JNK phosphorylation. The orphan nuclear receptor small heterodimer partner (SHP, NR0B2) acts as a transcriptional co-repressor of various genes. The aim of the present study was to investigate the role of SHP in APAP-evoked hepatotoxicity. We used lethal (750 mg/kg) or sublethal (300 mg/kg) doses of APAP-treated wild-type (WT), Shp knockout (Shp−/−), hepatocyte-specific Shp knockout (Shphep−/−), and Shp and Gadd45β double knockout (Shp−/−Gadd45β−/−) mice for in vivo studies. Primary mouse hepatocytes were used for a comparative in vitro study. SHP deficiency protected against APAP toxicity with an increased survival rate, decreased liver damage, and inhibition of prolonged hepatic JNK phosphorylation in mice, which was independent of APAP metabolism regulation. Furthermore, Shphep−/− mice showed diminished APAP hepatotoxicity compared with WT mice. SHP-deficient primary mouse hepatocytes also showed decreased cell death and inhibition of sustained JNK phosphorylation following toxic APAP treatment. While SHP expression declined, GADD45β expression increased after APAP treatment in WT mice. In Shp−/− mice, APAP-evoked GADD45β induction was significantly enhanced. Notably, the ameliorative effects of SHP deficiency on APAP-induced liver injury were abolished in Shp−/−Gadd45β−/− mice. The current study is the first to demonstrate that hepatocyte-specific SHP deficiency protects against APAP overdose-evoked hepatotoxicity in a JNK signaling regulation and GADD45β dependent manner. SHP is suggested to be a novel therapeutic target for APAP overdose treatment.
      PubDate: 2018-08-01
      DOI: 10.1007/s00204-018-2247-3
      Issue No: Vol. 92, No. 8 (2018)
       
  • Synthesis of interleukin 1 beta and interleukin 6 in human lymphocytes is
           stimulated by tributyltin
    • Authors: Shyretha Brown; Mariam Boules; Nafisa Hamza; Xiaofei Wang; Margaret Whalen
      Pages: 2573 - 2586
      Abstract: Tributyltin (TBT) is a widespread environmental contaminant that is present in human blood and other tissues. It has been shown to disrupt the immune function of human natural killer (NK) cells and to alter the secretion of a number of pro-inflammatory cytokines from immune cells. Secretion of both interleukin 1β (IL-1β) and interleukin 6 (IL-6) from human lymphocytes can be increased dependent upon the level of TBT exposure. This study shows that the TBT-induced increases in secretion of both cytokines are due to TBT-induced increases in the synthesis of these proteins and not simply because of the release of pre-existing cytokine. Furthermore, the data indicate that these TBT-induced increases in IL-1β and IL-6 synthesis require MAP kinase signaling pathways. Additionally, elevated synthesis of IL-1β and IL-6 seen at the highest exposures to TBT (200, 200, 50 nM) were accompanied by increases in the mRNA for these cytokines. TBT-induced increases in IL-1β and IL-6 mRNAs were also shown to be dependent on MAP kinase signaling. The study suggests that TBT has the capacity to increase immune cell production of these 2 important pro-inflammatory cytokines and that this increase is in part explained by increased mRNA for the cytokines.
      PubDate: 2018-08-01
      DOI: 10.1007/s00204-018-2248-2
      Issue No: Vol. 92, No. 8 (2018)
       
  • Perinatal exposure to a glyphosate-based herbicide impairs female
           reproductive outcomes and induces second-generation adverse effects in
           Wistar rats
    • Authors: María M. Milesi; Virginia Lorenz; Guillermina Pacini; María R. Repetti; Luisina D. Demonte; Jorgelina Varayoud; Enrique H. Luque
      Pages: 2629 - 2643
      Abstract: Glyphosate-based herbicides (GBHs) are the most globally used herbicides raising the risk of environmental exposition. Here, we investigated whether perinatal exposure to low doses of a GBH alters the female reproductive performance, and/or induced second-generation effects related to congenital anomalies or growth alterations. Pregnant rats (F0) received a GBH through food, in a dose of 2 mg (GBH-LD: GBH-low dose group) or 200 mg (GBH-HD: GBH-high dose group) of glyphosate/kg bw/day from gestational day (GD) 9 until weaning. Body weight gain and vaginal canal-opening of F1 females were recorded. Sexually mature F1 females were mated to evaluate their reproductive performance by assessing the pregnancy rate, and on GD19, the number of corpora lutea, the implantation sites (IS) and resorption sites. To analyze second-generation effects on F2 offspring, we analyzed the fetal morphology on GD19, and assessed the fetal length and weight, and the placental weight. GBH exposure neither altered the body weight gain of F1 females, nor vaginal opening onset. Although all GBH-exposed F1 rats became pregnant, a lower number of IS was detected. F2 offspring from both GBH groups showed delayed growth, evidenced by lower fetal weight and length, associated with a higher incidence of small for gestational age fetuses. In addition, higher placental weight and placental index were found in F2 offspring from GBH-HD dams. Surprisingly, structural congenital anomalies (conjoined fetuses and abnormally developed limbs) were detected in the F2 offspring from GBH-HD group. In conclusion, perinatal exposure to low doses of a GBH impaired female reproductive performance and induced fetal growth retardation and structural congenital anomalies in F2 offspring.
      PubDate: 2018-08-01
      DOI: 10.1007/s00204-018-2236-6
      Issue No: Vol. 92, No. 8 (2018)
       
  • Sensitization of colorectal cancer cells to irinotecan by the Survivin
           inhibitor LLP3 depends on XAF1 proficiency in the context of mutated p53
    • Authors: Christian Steigerwald; Birgit Rasenberger; Markus Christmann; Maja T. Tomicic
      Pages: 2645 - 2648
      Abstract: Survivin is a well-established target in experimental cancer therapy. While hardly expressed in normal tissues, it is over-expressed in most human tumors, including colorectal cancer (CRC). Different compartmentalization of Survivin enables its multiple functions as a key controller of cell division, apoptosis, stress-induced signaling and also of migration and metastasis. Because of the lack of its enzymatic activity, this oncoprotein is considered to be undruggable. Nevertheless, small-molecule interfacial inhibitors interfering with its dimerization and/or disrupting the Survivin-Ran protein complex were shown to be potent drugs causing Survivin proteasomal degradation and inducing apoptosis in cancer cells. Based on our results with different CRC cell lines, we show that the Survivin inhibitor LLP3 might be effective as mono-therapy in the subgroup of p53-proficient and also some p53-mutated tumors, independent of mismatch repair status. When combined with irinotecan, expression of the tumor suppressor X-linked inhibitor of apoptosis factor 1 (XAF1) plays a decisive role for sensitization of CRC cells to this first-line drug, however, only in the p53-mutated background. The combination treatment with IT should be avoided in p53-proficient tumors independent of XAF1 expression, since no sensitization to or even protection against moderate-toxic concentrations of IT might occur.
      PubDate: 2018-08-01
      DOI: 10.1007/s00204-018-2240-x
      Issue No: Vol. 92, No. 8 (2018)
       
  • Novel approach to integrated DNA adductomics for the assessment of in
           vitro and in vivo environmental exposures
    • Authors: Yuan-Jhe Chang; Marcus S. Cooke; Chiung-Wen Hu; Mu-Rong Chao
      Pages: 2665 - 2680
      Abstract: Adductomics is expected to be useful in the characterization of the exposome, which is a new paradigm for studying the sum of environmental causes of diseases. DNA adductomics is emerging as a powerful method for detecting DNA adducts, but reliable assays for its widespread, routine use are currently lacking. We propose a novel integrated strategy for the establishment of a DNA adductomic approach, using liquid chromatography-triple quadrupole tandem mass spectrometry (LC-QqQ-MS/MS), operating in constant neutral loss scan mode, screening for both known and unknown DNA adducts in a single injection. The LC-QqQ-MS/MS was optimized using a representative sample of 23 modified 2′-deoxyribonucleosides reflecting a range of biologically relevant DNA lesions. Six internal standards (ISTDs) were evaluated for their ability to normalize, and hence correct, possible variation in peak intensities arising from matrix effects, and the quantities of DNA injected. The results revealed that, with appropriate ISTDs adjustment, any bias can be dramatically reduced from 370 to 8.4%. Identification of the informative DNA adducts was achieved by triggering fragmentation spectra of target ions. The LC-QqQ-MS/MS method was successfully applied to in vitro and in vivo studies to screen for DNA adducts formed following representative environmental exposures: methyl methanesulfonate (MMS) and five N-nitrosamines. Interestingly, five new DNA adducts, induced by MMS, were discovered using our adductomic approach—an added strength. The proposed integrated strategy provides a path forward for DNA adductomics to become a standard method to discover differences in DNA adduct fingerprints between populations exposed to genotoxins, and facilitate the field of exposomics.
      PubDate: 2018-08-01
      DOI: 10.1007/s00204-018-2252-6
      Issue No: Vol. 92, No. 8 (2018)
       
  • Circadian clock pathway genes associated with colorectal cancer risk and
           prognosis
    • Authors: Dongying Gu; Shuwei Li; Shuai Ben; Mulong Du; Haiyan Chu; Zhengdong Zhang; Meilin Wang; Zuo-Feng Zhang; Jinfei Chen
      Pages: 2681 - 2689
      Abstract: Circadian clock genes influence biological processes and may be involved in tumorigenesis. We systematically evaluated genetic variants in the circadian clock pathway genes associated with colorectal cancer risk and survival. We evaluated the association of 119 single nucleotide polymorphisms (SNPs) in 27 circadian clock pathway genes with the risk of colorectal cancer in a case–control study (1150 cases and 1342 controls). The false discovery rate (FDR) method was applied to correct for multiple comparisons. Gene-based analysis was performed by the sequence kernel association test (SKAT). Cox proportional hazards regression was used to calculate the effects of SNPs on the overall survival of patients. We identified that compared to those with the G allele, individuals with the rs76436997 A allele in RORA had a significant 1.33-fold increased risk of colorectal cancer (P = 3.83 × 10− 4). Specifically, the GA/AA genotypes were related to an enhanced risk of colorectal cancer compared with that associated with the GG genotype, which was more common in patients with well and moderately differentiated tumors and Dukes A/B stages. The SNP rs76436997 significantly increased the overall survival time of colorectal cancer patients (P = 0.044). Furthermore, RNA-seq data showed that the mRNA levels of RORA were significantly lower in colorectal tumors than the paired normal tissues. Gene-based analysis revealed a significant association between RORA and colorectal cancer risk. These findings highlight the important roles of genetic variations in circadian clock pathway genes play in colorectal cancer risk and suggest that RORA is potentially related to colorectal carcinogenesis.
      PubDate: 2018-08-01
      DOI: 10.1007/s00204-018-2251-7
      Issue No: Vol. 92, No. 8 (2018)
       
  • On the necessity of careful interpretation of omics data
    • Authors: Albert Braeuning; Falko Frenzel; Alfonso Lampen
      Pages: 2701 - 2702
      PubDate: 2018-08-01
      DOI: 10.1007/s00204-018-2245-5
      Issue No: Vol. 92, No. 8 (2018)
       
  • Recent biomonitoring reports on phosphate ester flame retardants: a short
           review
    • Authors: Anne-Marie Saillenfait; Sophie Ndaw; Alain Robert; Jean-Philippe Sabaté
      Abstract: Organophosphate triesters (PEFRs) are used increasingly as flame retardants and plasticizers in a variety of applications, such as building materials, textiles, and electric and electronic equipment. They have been proposed as alternatives to brominated flame retardants. This updated review shows that biomonitoring has gained incrementally greater importance in evaluating human exposure to PEFRs, and it holds the advantage of taking into account the multiple potential sources and various intake pathways of PEFRs. Simultaneous and extensive internal exposure to a broad range of PEFRs have been reported worldwide. Their metabolites, mainly dialkyl or diaryl diesters, have been used as biomarkers of exposure and have been ubiquitously detected in the urine of adults and children in the general population. Concentrations and profiles of PEFR urinary metabolites are seen to be variable and are highly dependent on individual and environmental factors, including age, country regulation of flame retardants, and types and quantities of emissions in microenvironments, as well as analytical procedures. Additional large biomonitoring studies, using a broad range of urinary diesters and hydroxylated metabolites, would be useful to improve the validity of the biomarkers and to refine assessments of human exposure to PEFRs.
      PubDate: 2018-08-10
      DOI: 10.1007/s00204-018-2275-z
       
  • Chemical-induced contact allergy: from mechanistic understanding to risk
           prevention
    • Authors: Emanuela Corsini; Ayşe Başak Engin; Monica Neagu; Valentina Galbiati; Dragana Nikitovic; George Tzanakakis; Aristidis M. Tsatsakis
      Abstract: Chemical allergens are small molecules able to form a sensitizing complex once they bound to proteins. One of the most frequent manifestations of chemical allergy is contact hypersensitivity, which can have serious impact on quality of life. Allergic contact dermatitis is a predominantly CD8 + T cell-mediated immune disease, resulting in erythema and eczema. Chemical allergy is of considerable importance to the toxicologist, who has the responsibility of identifying and characterizing the allergenic potential of chemicals, and estimating the risk they pose to human health. This review aimed at exploring the phenomena of chemical-induced contact allergy starting from a mechanistic understanding, immunoregulatory mechanisms, passing through the potency of contract allergen until the hazard identification, pointing out the in vitro models for assessing contact allergen-induced cell activation and the risk prevention.
      PubDate: 2018-08-10
      DOI: 10.1007/s00204-018-2283-z
       
  • MicroRNA-942 mediates hepatic stellate cell activation by regulating BAMBI
           expression in human liver fibrosis
    • Authors: Le Tao; Dongying Xue; Dongxiao Shen; Wenting Ma; Jie Zhang; Xuefei Wang; Wei Zhang; Liu Wu; Kai Pan; Yanqin Yang; Zeribe C. Nwosu; Steven Dooley; Ekihiro Seki; Cheng Liu
      Abstract: MicroRNA (miRNA)-mediated gene regulation contributes to liver pathophysiology, including hepatic stellate cell (HSC) activation and fibrosis progression. Here, we investigated the role of miR-942 in human liver fibrosis. The expression of miR-942, HSC activation markers, transforming growth factor-beta pseudoreceptor BMP and activin membrane-bound inhibitor (BAMBI), as well as collagen deposition, were investigated in 100 liver specimens from patients with varying degree of hepatitis B virus (HBV)-related fibrosis. Human primary HSCs and the immortalized cell line (LX2 cells) were used for functional studies. We found that miR-942 expression was upregulated in activated HSCs and correlated inversely with BAMBI expression in liver fibrosis progression. Transforming growth factor beta (TGF-β) and lipopolyssacharide (LPS), two major drivers of liver fibrosis and inflammation, induce miR-942 expression in HSCs via Smad2/3 respective NF-κB/p50 binding to the miR-942 promoter. Mechanistically, the induced miR-942 degrades BAMBI mRNA in HSCs, thereby sensitizing the cells for fibrogenic TGF-β signaling and also partly mediates LPS-induced proinflammatory HSC fate. In conclusion, the TGF-β and LPS-induced miR-942 mediates HSC activation through downregulation of BAMBI in human liver fibrosis. Our study provides new insights on the molecular mechanism of HSC activation and fibrosis.
      PubDate: 2018-08-10
      DOI: 10.1007/s00204-018-2278-9
       
  • Effect of acute exposure to toluene on cortical excitability,
           neuroplasticity, and motor learning in healthy humans
    • Authors: Fatemeh Yavari; Christoph van Thriel; Michael A. Nitsche; Min-Fang Kuo
      Abstract: Toluene is a well-known neurotoxic organic solvent and a major component of many industrial and commercial products such as adhesives, paint thinners and gasoline. Many workers are regularly exposed to toluene in their working environment and occupational exposure limits (OELs) have been set to avoid adverse health effects. These OELs or short-term exposure limits vary from 14 to 300 ppm across countries partly due to heterogeneity of the findings from animal and human studies about its neurotoxic effects and the evaluation of the adversity of the underlying mechanisms. Furthermore, its acute neurophysiological effects remain poorly understood in humans. The purpose of this study was to investigate the effects of acute exposure to toluene on cortical excitability, plasticity, and implicit motor learning in healthy volunteers. Seventeen subjects were assessed with different transcranial magnetic stimulation measurements: motor thresholds, short-latency intracortical inhibition and intracortical facilitation, and short-interval afferent inhibition before and after clean air or toluene (single peak of 200 ppm) administration. Furthermore, we evaluated long-term potentiation-like neuroplasticity induced by anodal transcranial direct current stimulation (tDCS) over the motor cortex, and the participants conducted a motor sequence learning task, the serial reaction time task. Our findings revealed that toluene abolished the plasticity induced by anodal tDCS, attenuated intracortical facilitation, and increased inhibition in the short-latency afferent inhibition measure, while cortico-spinal excitability and intracortical inhibition were not affected. On the behavioural level, toluene did not alter performance of the motor learning task. These results suggest that toluene might act by modulating NMDA receptor activity, as well as cortical glutamatergic and cholinergic neurotransmission in the human brain. This study encourages further research to obtain more knowledge about mechanisms of action and effects of toluene on both naïve and chronically exposed populations.
      PubDate: 2018-08-10
      DOI: 10.1007/s00204-018-2277-x
       
  • The metabolic fate of fenclozic acid in chimeric mice with a humanized
           liver
    • Authors: Anja Ekdahl; Lars Weidolf; Matthew Baginski; Yoshio Morikawa; Richard A. Thompson; Ian D. Wilson
      Abstract: The metabolic fate of the human hepatotoxin fenclozic acid ([2-(4-chlorophenyl)-1,3-thiazol-4-yl]acetic acid) (Myalex) was studied in normal and bile-cannulated chimeric mice with a humanized liver, following oral administration of 10 mg/kg. This in vivo animal model was investigated to assess its utility to study “human” metabolism of fenclozic acid, and in particular to explore the formation of electrophilic reactive metabolites (RMs), potentially unique to humans. Metabolism was extensive, particularly involving the carboxylic acid-containing side chain. Metabolism resulted in the formation of a large number of metabolites and involved biotransformation via both oxidative and conjugative routes. The oxidative metabolites detected included a variety of hydroxylations as well as cysteinyl-, N-acetylcysteinyl-, and cysteinylglycine metabolites. The latter resulted from the formation of glutathione adducts/conjugates providing evidence for the production of RMs. The production of other classes of RMs included acyl-glucuronides, and the biosynthesis of acyl carnitine, taurine, glutamine, and glycine conjugates via potentially reactive acyl-CoA intermediates was also demonstrated. A number of unique “human” metabolites, e.g., those providing evidence for side-chain extension, were detected in the plasma and excreta of the chimeric liver-humanized mice that were not previously characterised in, e.g., the excreta of rat and C57BL/6 mice. The different pattern of metabolism seen in these chimeric mice with a humanized liver compared to the conventional rodents may offer clues to the factors that contributed to the drug-induced liver injury seen in humans.
      PubDate: 2018-08-09
      DOI: 10.1007/s00204-018-2274-0
       
  • Correction to: Glucuronidation of deoxynivalenol (DON) by different animal
           species: identification of iso-DON glucuronides and iso-deepoxy-DON
           glucuronides as novel DON metabolites in pigs, rats, mice, and cows
    • Authors: Heidi E. Schwartz-Zimmermann; Christian Hametner; Veronika Nagl; Iris Fiby; Lukas Macheiner; Janine Winkler; Sven Dänicke; Erica Clark; James J. Pestka; Franz Berthiller
      Abstract: The original article can be found online.
      PubDate: 2018-08-07
      DOI: 10.1007/s00204-018-2273-1
       
  • Inhibition and stimulation of the human breast cancer resistance protein
           as in vitro predictor of drug–drug interactions of drugs of abuse
    • Authors: Lea Wagmann; Hans H. Maurer; Markus R. Meyer
      Abstract: Transporter-mediated drug–drug interactions (DDI) may induce adverse clinical events. As drugs of abuse (DOA) are marketed without preclinical safety studies, only very limited information about interplay with membrane transporters are available. Therefore, 13 DOA of various classes were tested for their in vitro affinity to the human breast cancer resistance protein (hBCRP), an important efflux transporter. As adenosine 5′-triphosphate (ATP) hydrolysis is crucial for hBCRP activity, adenosine 5′-diphosphate (ADP) formation was measured and used as in vitro marker for hBCRP ATPase activity. ADP quantification was performed by hydrophilic interaction liquid chromatography coupled to high-resolution tandem mass spectrometry and its amount in test compound incubations was compared to that in reference incubations using the hBCRP substrate sulfasalazine or the hBCRP inhibitor orthovanadate. If DOA caused stimulation or inhibition, further investigations such as Michaelis–Menten kinetic modeling or IC50 value determination were conducted. Among the tested DOA, seven compounds showed statistically significant hBCRP ATPase stimulation. The entactogen 3,4-BDB and the plant alkaloid mitragynine were identified as strongest stimulators. Their affinity to the hBCRP ATPase was lower than that of sulfasalazine but comparable to that of rosuvastatin, another hBCRP model substrate. Five DOA showed statistically significant hBCRP ATPase inhibition. Determination of IC50 values identified the synthetic cannabinoid receptor agonists JWH-200 and WIN 55,212-2 as the strongest inhibitors comparable to orthovanadate. The present study clearly demonstrated that tested DOA show in part high affinities to the hBCRP within the range of model substrates or inhibitors. Thus, there is a risk of hBCRP-mediated DDI, which needs to be considered in clinical settings.
      PubDate: 2018-08-06
      DOI: 10.1007/s00204-018-2276-y
       
  • Urinary biomarkers of exposure to the mycoestrogen zearalenone and its
           modified forms in German adults
    • Authors: Nurshad Ali; Gisela H. Degen
      Abstract: Zearalenone (ZEN), a mycotoxin with estrogenic activity, can exert adverse endocrine effects in mammals and is thus of concern for humans. ZEN is found in cereal crops and grain-based foods, often along with modified (‘masked’) forms usually not detected in routine contaminant analysis, e.g., ZEN-O-β-glucosides and ZEN-14-sulfate. These contribute to mycoestrogen exposure, as they are cleaved in the gastrointestinal tract to ZEN, and further metabolized in animals and humans to α- and β-zearalenol (α-ZEL and β-ZEL). ZEN and its metabolites are mainly excreted as conjugates in urine, allowing to monitor human exposure by a biomarker-based approach. Here, we report on a new study in German adults (n = 60) where ZEN, α-ZEL, and β-ZEL were determined by LC-MS/MS analysis after enzymatic hydrolysis and immunoaffinity column clean-up of the aglycones in urines. Biomarkers were detected in all samples: ZEN ranges 0.04–0.28 (mean 0.10 ± 0.05; median 0.07) ng/mL; α-ZEL ranges 0.06–0.45 (mean 0.16 ± 0.07; median 0.13) ng/mL, and β-ZEL ranges 0.01–0.20 (mean 0.05 ± 0.04; median 0.03) ng/mL. Notably, average urinary levels of α-ZEL, the more potent estrogenic metabolite, are higher than those of ZEN, while β-ZEL (less estrogenic than ZEN) is found at lower levels than the parent mycotoxin. Similar results were found in ten persons who collected multiple urine samples to gain more insight into temporal fluctuations in ZEN biomarker levels; here some urines had higher maximal concentrations of total ZEN (the sum of ZEN, α-ZEL, and β-ZEL) with 1.6 and 1.01 ng/mL, i.e., more than those found in the majority of other urines. A preliminary approach to translate the new urinary biomarker data into dietary mycotoxin intake suggests that exposure of most individuals in our cohort is probably below the tolerable daily intake (TDI) of 0.25 µg/kg b.w. set by EFSA as group value for ZEN and its modified forms while that of some individuals exceed it. In conclusion, biomonitoring can help to assess consumer exposure to the estrogenic mycotoxin ZEN and its modified forms and to identify persons at higher risk.
      PubDate: 2018-07-06
      DOI: 10.1007/s00204-018-2261-5
       
  • Confounding influence of tamoxifen in mouse models of Cre
           recombinase-induced gene activity or modulation
    • Authors: Seddik Hammad; Amnah Othman; Christoph Meyer; Ahmad Telfah; Joerg Lambert; Bedair Dewidar; Julia Werle; Zeribe Chike Nwosu; Abdo Mahli; Christof Dormann; Yan Gao; Kerry Gould; Mei Han; Xiaodong Yuan; Mikheil Gogiashvili; Roland Hergenröder; Claus Hellerbrand; Maria Thomas; Matthias Philip Ebert; Salah Amasheh; Jan G. Hengstler; Steven Dooley
      Abstract: Tamoxifen (TAM) is commonly used for cell type specific Cre recombinase-induced gene inactivation and in cell fate tracing studies. Inducing a gene knockout by TAM and using non-TAM exposed mice as controls lead to a situation where differences are interpreted as consequences of the gene knockout but in reality result from TAM-induced changes in hepatic metabolism. The degree to which TAM may compromise the interpretation of animal experiments with inducible gene expression still has to be elucidated. Here, we report that TAM strongly attenuates CCl4-induced hepatotoxicity in male C57Bl/6N mice, even after a 10 days TAM exposure-free period. TAM decreased (p < 0.0001) the necrosis index and the level of aspartate- and alanine transaminases in CCl4-treated compared to vehicle-exposed mice. TAM pretreatment also led to the downregulation of CYP2E1 (p = 0.0045) in mouse liver tissue, and lowered its activity in CYP2E1 expressing HepG2 cell line. Furthermore, TAM increased the level of the antioxidant ascorbate, catalase, SOD2, and methionine, as well as phase II metabolizing enzymes GSTM1 and UGT1A1 in CCl4-treated livers. Finally, we found that TAM increased the presence of resident macrophages and recruitment of immune cells in necrotic areas of the livers as indicated by F4/80 and CD45 staining. In conclusion, we reveal that TAM increases liver resistance to CCl4-induced toxicity. This finding is of high relevance for studies using the tamoxifen-inducible expression system particularly if this system is used in combination with hepatotoxic compounds such as CCl4.
      PubDate: 2018-07-04
      DOI: 10.1007/s00204-018-2254-4
       
 
 
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