title: Suppression of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine-induced DNA damage in rat colon after grapefruit juice intake.
abstract: The influence of grapefruit juice intake on 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)-induced colon DNA damage was examined using comet assay in F344 rats given 60 mg/kg of PhIP by gavage. F344 rats allowed free access to grapefruit juice for 5 days experienced clearly reduced DNA damage in the colon to a 40% level of control rats. The suppression of PhIP-induced colon DNA damage depended on the grapefruit juice concentrations. The serum concentration of PhIP was compared between grapefruit juice-pretreated and non-pretreated rats, but showed no significant difference in the areas under their concentration-time curves, peak values and half lives of PhIP. Furthermore, no obvious difference was found in the liver capacity for mutagenic activation of PhIP in Ames assay between grapefruit juice-pretreated and non-pretreated rats. These results suggest that grapefruit juice suppresses PhIP-induced colon DNA damage by a mechanism independent of PhIP absorption in the intestine.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba-ku, 980-8578, Sendai, Japan. miyata@mail.pharm.tohoku.ac.jp
authors.forename: Masaaki
authors.initials: M
authors.lastname: Miyata
authors.forename: Hiroki
authors.initials: H
authors.lastname: Takano
authors.forename: Koichi
authors.initials: K
authors.lastname: Takahashi
authors.forename: Yu F
authors.initials: YF
authors.lastname: Sasaki
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Yamazoe
mesh_terms: D000818:Animals; D001628:Beverages; D002273:Carcinogens / Q000037:antagonists & inhibitors / Q000493:pharmacokinetics / Q000633:toxicity; D002957:Citrus; D003106:Colon / Q000187:drug effects* / Q000473:pathology; D004247:DNA / Q000187:drug effects*; D004249:DNA Damage; D007093:Imidazoles / Q000037:antagonists & inhibitors / Q000493:pharmacokinetics / Q000633:toxicity*; D007700:Kinetics; D008517:Phytotherapy; D051381:Rats; D011916:Rats, Inbred F344; D013997:Time Factors
chemical_list: D002273:Carcinogens; D007093:Imidazoles; D004247:DNA; C049584:2-amino-1-methyl-6-phenylimidazo(4,5-b)pyridine