title: Down-regulation of liver drug-metabolizing enzymes in a murine model of chronic renal failure.
abstract: Drug metabolism could be altered in patients with chronic renal failure (CRF). In rats, this phenomenon is related to a decrease in liver cytochrome P450 (P450) and phase II enzymes, particularly N-acetyltransferase 2 (NAT2). This study attempted to determine the effects of CRF on liver P450 isoforms and NAT2 expressions by using a CRF mouse model. Two groups of mice were studied: CRF induced by 3/4 nephrectomy and control. Liver protein expression and mRNA levels of the major P450 isoforms involved in drug metabolism (CYP1A2, 2C29, 2D, 2E1, and 3A11) and NAT2 were measured by Western blot and real-time polymerase chain reaction (PCR), respectively. CYP3A activity was also assessed by the N-demethylation of erythromycin. Results showed a significant reduction in the protein expression of CYP1A2 (56%), 2C29 (31%), and 3A11 (37%) in CRF mice compared with control animals. Real-time PCR revealed a similar reduction in mRNA levels of CYP1A2, 2C29, and 3A11 (59, 56, and 37%, respectively), in CRF mice. There was no significant modification in protein expression and mRNA of CYP2D and 2E1. Compared with control animals, CRF mice displayed a 25% reduction in N-demethylation of erythromycin. For NAT2, protein expression decreased by 33% and mRNA levels decreased by 23%. In conclusion, this study demonstrates that protein expression of liver CYP1A2, CYP2C29, and CYP3A11 is down-regulated in CRF mice, secondary to reduced gene expression. Phase II enzymes are similarly affected by CRF. Our results will allow the use of knockout mice to determine the mechanism underlying CRF-induced down-regulation of liver drug-metabolizing enzymes.
authors.affiliation: Centre de Recherche de l'Hôpital Maisonneuve-Rosemont, Faculté de Médecine, Université de Montréal, Québec, Canada.
authors.forename: Mélina
authors.initials: M
authors.lastname: Dani
authors.forename: Caroline
authors.initials: C
authors.lastname: Boisvert
authors.forename: Josée
authors.initials: J
authors.lastname: Michaud
authors.forename: Judith
authors.initials: J
authors.lastname: Naud
authors.forename: Stéphane
authors.initials: S
authors.lastname: Lefrançois
authors.forename: Francois A
authors.initials: FA
authors.lastname: Leblond
authors.forename: Vincent
authors.initials: V
authors.lastname: Pichette
mesh_terms: D000818:Animals; D001191:Arylamine N-Acetyltransferase / Q000235:genetics / Q000378:metabolism; D001711:Biotransformation; D003404:Creatinine / Q000097:blood; D019388:Cytochrome P-450 CYP1A2 / Q000235:genetics / Q000378:metabolism; D051544:Cytochrome P-450 CYP3A / Q000235:genetics / Q000378:metabolism; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics / Q000378:metabolism*; D004195:Disease Models, Animal; D015536:Down-Regulation; D004917:Erythromycin / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D007676:Kidney Failure, Chronic / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D008099:Liver / Q000201:enzymology* / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009392:Nephrectomy; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014508:Urea / Q000097:blood
chemical_list: D007527:Isoenzymes; D012333:RNA, Messenger; D004917:Erythromycin; D014508:Urea; D003577:Cytochrome P-450 Enzyme System; D003404:Creatinine; C504573:CYP1A2 protein, human; D019388:Cytochrome P-450 CYP1A2; D051544:Cytochrome P-450 CYP3A; D001191:Arylamine N-Acetyltransferase; C524206:Nat2 enzyme, mouse