title: Single-dose ethanol administration downregulates expression of cytochrome p450 2E1 mRNA in aldehyde dehydrogenase 2 knockout mice.
abstract: The polymorphism of aldehyde dehydrogenase 2 (ALDH2), denoted ALDH2*2, is very common in East Asian origin. Acetaldehyde, an intermediate metabolite of ethanol, is metabolized very slowly in people with ALDH2*2 because the mutant ALDH2 protein lacks the activity of acetaldehyde metabolism. On the other hand, it is well established that one of the cytochrome P450 enzymes, CYP2E1, is an activator of carcinogens (e.g., nitorosamines) and a generator of oxidative stress, and it is shown that CYP2E1 was induced by ethanol via gene transcriptional regulation. In the present study, to examine the consequences of ALDH2 polymorphism on transcriptional regulation of CYP2E1 in liver tissue, Aldh2+/+ and Aldh2-/- mice were orally administered 5 g/kg body weight of ethanol and the levels of CYP2E1 mRNA in liver tissue then analyzed. The level of CYP2E1 mRNA 12h after the ethanol administration tended to be higher than the 0-h group in Aldh2+/+ mice, however, it was significantly lower than the 0-h group in Aldh2-/- mice. These findings suggest that single-dose ethanol administration downregulates the expression of cytochrome p450 2E1 mRNA in the presence of inactive ALDH2.
authors.affiliation: Department of Social and Environmental Medicine, Saga Medical School, Saga 849-8501, Japan. matsumoa@cc.saga-u.ac.jp
authors.forename: Akiko
authors.initials: A
authors.lastname: Matsumoto
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Kawamoto
authors.forename: Mikako
authors.initials: M
authors.lastname: Horita
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Takahashi
authors.forename: Toyohi
authors.initials: T
authors.lastname: Isse
authors.forename: Tsunehiro
authors.initials: T
authors.lastname: Oyama
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Ichiba
mesh_terms: D000284:Administration, Oral; D000444:Aldehyde Dehydrogenase / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D000071396:Aldehyde Dehydrogenase, Mitochondrial; D000818:Animals; D002492:Central Nervous System Depressants / Q000008:administration & dosage*; D019392:Cytochrome P-450 CYP2E1 / Q000235:genetics / Q000378:metabolism*; D015536:Down-Regulation; D000431:Ethanol / Q000008:administration & dosage*; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects*; D008099:Liver / Q000187:drug effects* / Q000201:enzymology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D012333:RNA, Messenger / Q000378:metabolism*; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: D002492:Central Nervous System Depressants; D012333:RNA, Messenger; D000431:Ethanol; D019392:Cytochrome P-450 CYP2E1; C515029:ALDH2 protein, mouse; D000444:Aldehyde Dehydrogenase; D000071396:Aldehyde Dehydrogenase, Mitochondrial