title: Selective protection of curcumin against carbon tetrachloride-induced inactivation of hepatic cytochrome P450 isozymes in rats.
abstract: We investigated the effects of curcumin, a major antioxidant constituent of turmeric, on hepatic cytochrome P450 (CYP) activity in rats. Wistar rats received curcumin-containing diets (0.05, 0.5 and 5 g/kg diet) with or without injection of carbon tetrachloride (CCl(4)). The hepatic CYP content and activities of six CYP isozymes remained unchanged by curcumin treatment, except for the group treated with the extremely high dose (5 g/kg). This suggested that daily dose of curcumin does not cause CYP-mediated interaction with co-administered drugs. Chronic CCl(4) injection drastically decreased CYP activity, especially CYP2E1 activity, which is involved in the bioactivation of CCl(4), thereby producing reactive free radicals. Treatment with curcumin at 0.5 g/kg alleviated the CCl(4)-induced inactivation of CYPs 1A, 2B, 2C and 3A isozymes, except for CYP2E1. The lack of effect of curcumin on CYP2E1 damage might be related to suicidal radical production by CYP2E1 on the same enzyme. It is speculated that curcumin inhibited CCl(4)-induced secondary hepatic CYPs damage through its antioxidant properties. Our results demonstrated that CYP isozyme inactivation in rat liver caused by CCl(4) was inhibited by curcumin. Dietary intake of curcumin may protect against CCl(4)-induced hepatic CYP inactivation via its antioxidant properties, without inducing hepatic CYPs.
authors.affiliation: Division of Applied Food Research, National Institute of Health and Nutrition, Shinjuku-ku, Japan.
authors.forename: Tomomi
authors.initials: T
authors.lastname: Sugiyama
authors.forename: Jun-ichi
authors.initials: J
authors.lastname: Nagata
authors.forename: Azumi
authors.initials: A
authors.lastname: Yamagishi
authors.forename: Kaori
authors.initials: K
authors.lastname: Endoh
authors.forename: Morio
authors.initials: M
authors.lastname: Saito
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Yamada
authors.forename: Shizuo
authors.initials: S
authors.lastname: Yamada
authors.forename: Keizo
authors.initials: K
authors.lastname: Umegaki
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000008:administration & dosage / Q000627:therapeutic use*; D001835:Body Weight / Q000187:drug effects; D002252:Carbon Tetrachloride Poisoning / Q000201:enzymology / Q000517:prevention & control*; D003474:Curcumin / Q000008:administration & dosage / Q000627:therapeutic use*; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation; D008099:Liver / Q000187:drug effects* / Q000201:enzymology / Q000473:pathology; D008297:Male; D009929:Organ Size / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar
chemical_list: D000975:Antioxidants; D003577:Cytochrome P-450 Enzyme System; D003474:Curcumin