title: Regulation of cigarette smoke-induced cytochrome P4501A1 gene expression in osteogenic disorder Shionogi rat liver and in lung by large ascorbic acid dose.
abstract: The effects of a large ascorbic acid dose on cytochrome P4501A1 gene expression induced by cigarette smoke exposure was studied in Osteogenic Disorder Shionogi rats, which lack ascorbic acid biosynthesis. The rats were divided into four groups and were administered either a minimal amount (4 mg/day, 4S and 4C) or a large amount (40 mg/day, 40S and 40C) of ascorbic acid. The 4S group and 40S group were daily exposed to cigarette smoke for 2 hours, while the 4C group and 40C group were not. At the end of the 25-day experiment, the rats were killed. The cytochrome P4501A1 mRNA level both in the liver and lung was measured by a competitive reverse transcription-polymerase chain reaction method. When a minimal amount of ascorbic acid was administered, the cytochrome P4501A1 mRNA increased in the liver of the cigarette smoke-exposed group (4S) compared with the control group (4C). On the other hand, when a large amount of ascorbic acid was administered, this increase was not observed in the cigarette smoke-induced group (40S) in liver. On the other hand, in lung, an increased mRNA level in 4S group was not decreased by large ascorbic acid administration (40S). This is the first direct mRNA-level evidence of the effects of a large ascorbic acid dose on the gene expression stimulated by cigarette smoke.
authors.affiliation: Institute of Environmental Science for Human Life, Ochanomizu University, Tokyo, Japan.
authors.forename: E
authors.initials: E
authors.lastname: Ueta
authors.forename: E
authors.initials: E
authors.lastname: Suzuki
authors.forename: E
authors.initials: E
authors.lastname: Nanba
authors.forename: Y
authors.initials: Y
authors.lastname: Tadokoro
authors.forename: Y
authors.initials: Y
authors.lastname: Otsuka
authors.forename: T
authors.initials: T
authors.lastname: Kurata
mesh_terms: D000818:Animals; D001205:Ascorbic Acid / Q000008:administration & dosage / Q000494:pharmacology*; D001847:Bone Diseases / Q000201:enzymology / Q000235:genetics; D019363:Cytochrome P-450 CYP1A1 / Q000235:genetics*; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D008099:Liver / Q000187:drug effects* / Q000201:enzymology*; D008168:Lung / Q000187:drug effects* / Q000201:enzymology*; D008297:Male; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D011922:Rats, Mutant Strains; D012907:Smoking / Q000009:adverse effects*
chemical_list: D012333:RNA, Messenger; D019363:Cytochrome P-450 CYP1A1; D001205:Ascorbic Acid