title: Inhibitory potential of herbal medicines on human cytochrome P450-mediated oxidation: properties of umbelliferous or citrus crude drugs and their relative prescriptions.
abstract: To investigate the possible drug interaction with herbal medicine, hot water decoctions or 40% ethanol infusions of several Umbelliferous or Citrus crude drugs and their prescriptions were examined in vitro for their abilities to inhibit human cytochrome P450 3A (CYP3A). Addition of each decoction or infusion from Baizhi (Angelica dahurica and varieties), Qianghuo (Notopterygium incisum or N. forbesii), Duhuo (Angelica biserrata), Fangfeng (Saposhnikovia divaricata), Danggui (Angelicasinensis), Zhishi or Zhiqiao (Citrus aurantium) resulted in various degrees of human CYP3A inhibition as determined by microsomal testosterone 6beta-hydroxylation. The inhibitory potency was consistent with the abundance of the hydrophobic components for each sample. Experiments on the infusion of a Japanese Baizhi (BZ1) showed the major role of furanocoumarins on human CYP3A inhibition. Some of the crude drugs and a related prescription showed increased inhibition after the preincubation, suggesting the involvement of a mechanism-based inhibition. Some formulated prescriptions, however, showed intense inhibition with their hydrophobic fractions rather than with their hydrophobic fractions, suggesting that components other than furanocoumarins in herbal prescriptions may also cause CYP3A inhibition. These results indicate the necessity of intensive investigations on the possible drug interaction with traditional medicines.
authors.affiliation: Division of Drug Metabolism and Molecular Toxicology, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan.
authors.forename: L Q
authors.initials: LQ
authors.lastname: Guo
authors.forename: M
authors.initials: M
authors.lastname: Taniguchi
authors.forename: Q Y
authors.initials: QY
authors.lastname: Chen
authors.forename: K
authors.initials: K
authors.lastname: Baba
authors.forename: Y
authors.initials: Y
authors.lastname: Yamazoe
mesh_terms: D001189:Aryl Hydrocarbon Hydroxylases; D002957:Citrus; D051544:Cytochrome P-450 CYP3A; D065607:Cytochrome P-450 Enzyme Inhibitors; D003577:Cytochrome P-450 Enzyme System / Q000502:physiology*; D004365:Drugs, Chinese Herbal / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D029001:Herbal Medicine; D006801:Humans; D008862:Microsomes, Liver / Q000187:drug effects / Q000201:enzymology; D010084:Oxidation-Reduction / Q000187:drug effects; D010089:Oxidoreductases, N-Demethylating / Q000037:antagonists & inhibitors* / Q000502:physiology*; D010936:Plant Extracts / Q000494:pharmacology; D013250:Steroid Hydroxylases / Q000037:antagonists & inhibitors
chemical_list: D065607:Cytochrome P-450 Enzyme Inhibitors; D004365:Drugs, Chinese Herbal; D004791:Enzyme Inhibitors; D010936:Plant Extracts; C067415:qiang-huo; D003577:Cytochrome P-450 Enzyme System; D013250:Steroid Hydroxylases; D001189:Aryl Hydrocarbon Hydroxylases; D051544:Cytochrome P-450 CYP3A; C022657:steroid hormone 6-beta-hydroxylase; D010089:Oxidoreductases, N-Demethylating