title: Mechanism-based inhibition of CYP3A4 and CYP2D6 by Indonesian medicinal plants.
abstract: Thirty samples of Indonesian medicinal plants were tested for their mechanism-based inhibition on cytochrome P450 3A4 (CYP3A4) and CYP2D6 via erythromycin N-demethylation and dextromethorphan O-demethylation activities in human liver microsomes. From screening with 0 and 20min preincubation at 0.5mg/ml of methanol extracts, five plants (Cinnamomum burmani bark, Foeniculum vulgare seed, Strychnos ligustrina wood, Tinospora crispa stem, and Zingiber cassumunar rhizome) showed more than 30% increase of CYP3A4 inhibition, while three (Alpinia galanga rhizome, Melaleuca leucadendron leaf, and Piper nigrum fruit) showed more than 30% increase of CYP2D6 inhibition. In these eight plants, Foeniculum vulgare seed, Cinnamomum burmani bark, and Strychnos ligustrina wood showed time-dependent inhibition on CYP3A4 and Piper nigrum fruit and Melaleuca leucadendron leaf on CYP2D6. Among these, four plants other than Melaleuca leucadendron revealed NADPH-dependent inhibition. Thus, Foeniculum vulgare, Cinnamomum burmani, and Strychnos ligustrina should contain mechanism-based inhibitors on CYP3A4 and Piper nigrum contain that on CYP2D6.
authors.affiliation: Institute of Natural Medicine, Toyama Medical and Pharmaceutical University, 2630-Sugitani, Toyama 930-0194, Japan.
authors.lastname: Subehan
authors.forename: Tepy
authors.initials: T
authors.lastname: Usia
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Iwata
authors.forename: Shigetoshi
authors.initials: S
authors.lastname: Kadota
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Tezuka
mesh_terms: D065690:Cytochrome P-450 CYP2D6 Inhibitors; D051544:Cytochrome P-450 CYP3A; D065607:Cytochrome P-450 Enzyme Inhibitors; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D041743:Herb-Drug Interactions; D007214:Indonesia; D009249:NADP / Q000378:metabolism; D010936:Plant Extracts / Q000494:pharmacology*; D010946:Plants, Medicinal
chemical_list: D065690:Cytochrome P-450 CYP2D6 Inhibitors; D065607:Cytochrome P-450 Enzyme Inhibitors; D004791:Enzyme Inhibitors; D010936:Plant Extracts; D009249:NADP; D051544:Cytochrome P-450 CYP3A; C510163:CYP3A4 protein, human