title: Inter-donor variability of phase I/phase II metabolism of three reference drugs in cryopreserved primary human hepatocytes in suspension and monolayer.
abstract: Cytochrome P450s (CYPs), UDP-glucuronosyltransferases (UGTs) and sulfotransferases (SULTs) are the most important enzymes for metabolic clearance. Characterization of phase I and phase II metabolism of a given drug in cellular models is therefore important for an adequate interpretation of the role of drug metabolism in toxicity. We investigated phase I (CYP) and phase II (UGT and SULT) metabolism of three drugs related to drug-induced liver injury (DILI), namely acetaminophen (APAP), diclofenac (DF) and tolcapone (TC), in cryopreserved primary human hepatocytes from 5 donors in suspension and monolayer. The general phase II substrate 7-hydroxycoumarin (7-HC) was included for comparison. Our results show that the decrease in CYP, UGT and SULT activity after plating is substrate dependent. As a consequence the phase I/phase II metabolism ratio is significantly affected, with a shift in monolayer towards phase I metabolism for TC and towards phase II metabolism for APAP and DF. Inter-donor variability in drug metabolism is significant, especially in sulfation of 7-HC or APAP. As CYP, UGT and SULT metabolism may lead to bioactivation and/or detoxification of drugs, a changed ratio in phase I/phase II metabolism may have important consequences for metabolism-related toxicity.
authors.affiliation: AIMMS-Division of Molecular Toxicology, Department of Chemistry & Pharmaceutical Sciences, VU University Amsterdam, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands.
authors.forename: Shalenie P
authors.initials: SP
authors.lastname: den Braver-Sewradj
authors.affiliation: AIMMS-Division of Molecular Toxicology, Department of Chemistry & Pharmaceutical Sciences, VU University Amsterdam, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands.
authors.forename: Michiel W
authors.initials: MW
authors.lastname: den Braver
authors.affiliation: AIMMS-Division of Molecular Toxicology, Department of Chemistry & Pharmaceutical Sciences, VU University Amsterdam, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands.
authors.forename: Nico P E
authors.initials: NP
authors.lastname: Vermeulen
authors.affiliation: AIMMS-Division of Molecular Toxicology, Department of Chemistry & Pharmaceutical Sciences, VU University Amsterdam, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands.
authors.forename: Jan N M
authors.initials: JN
authors.lastname: Commandeur
authors.affiliation: Kaly-Cell, 20A Rue du Général Leclerc, France; Université de Franche-Comté, Besançon, France.
authors.forename: Lysiane
authors.initials: L
authors.lastname: Richert
authors.affiliation: AIMMS-Division of Molecular Toxicology, Department of Chemistry & Pharmaceutical Sciences, VU University Amsterdam, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands. Electronic address: j.c.vos@vu.nl.
authors.forename: J Chris
authors.initials: JC
authors.lastname: Vos
mesh_terms: D000082:Acetaminophen / Q000494:pharmacology*; D000368:Aged; D001577:Benzophenones / Q000494:pharmacology*; D002478:Cells, Cultured; D015925:Cryopreservation; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D004008:Diclofenac / Q000494:pharmacology*; D005260:Female; D014453:Glucuronosyltransferase / Q000378:metabolism*; D022781:Hepatocytes / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D009596:Nitrophenols / Q000494:pharmacology*; D015238:Sulfotransferases / Q000378:metabolism*; D000077867:Tolcapone; D014468:Umbelliferones / Q000494:pharmacology
chemical_list: D001577:Benzophenones; D009596:Nitrophenols; D014468:Umbelliferones; D004008:Diclofenac; D000082:Acetaminophen; C031477:7-hydroxycoumarin; D003577:Cytochrome P-450 Enzyme System; D000077867:Tolcapone; D014453:Glucuronosyltransferase; D015238:Sulfotransferases
keywords: Cryopreserved hepatocytes; Cytochrome P450; DILI; Sulfotransferase; UDP glucuronosyltransferase