title: Inhibitory effects of gypenosides on seven human cytochrome P450 enzymes in vitro.
abstract: Among the various possible causes for drug interactions, pharmacokinetic factors such as inhibition of drug-metabolizing enzymes, especially cytochrome P450 (CYP) enzymes, are regarded as the most frequent and clinically important. Gypenosides is widely used as functional food and over-the-counter drug in East Asia. In this study, the in vitro inhibitory effects of gypenosides on the major human CYP enzymes (CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, and CYP3A4) activities in human liver microsomes were examined using liquid chromatography-tandem mass spectrometry. Gypenosides showed the strongest inhibition of CYP2D6, followed by CYP2C8, CYP3A4 and CYP2C9. The IC50 values were 1.61 μg/mL, 20.06 μg/mL, 34.76 μg/mL (CYP3A4/midazolam), 46.73 μg/mL (CYP3A4/testosterone), and 54.52 μg/mL, respectively. Gypenosides exhibited competitive inhibition of CYP2D6 (Ki=1.18). In conclusion, Gypenosides might cause herb-drug interactions via inhibition of CYP2D6. An in vivo study is needed to examine this further.
authors.affiliation: Department of Clinical Pharmacology, Shuguang Hospital Affiliated to Shanghai University of TCM, Shanghai, China.
authors.forename: Min
authors.initials: M
authors.lastname: He
authors.forename: Jian
authors.initials: J
authors.lastname: Jiang
authors.forename: Furong
authors.initials: F
authors.lastname: Qiu
authors.forename: Songcan
authors.initials: S
authors.lastname: Liu
authors.forename: Peng
authors.initials: P
authors.lastname: Peng
authors.forename: Chenglu
authors.initials: C
authors.lastname: Gao
authors.forename: Ping
authors.initials: P
authors.lastname: Miao
mesh_terms: D001189:Aryl Hydrocarbon Hydroxylases / Q000037:antagonists & inhibitors / Q000378:metabolism; D019388:Cytochrome P-450 CYP1A2 / Q000378:metabolism; D065609:Cytochrome P-450 CYP1A2 Inhibitors; D065702:Cytochrome P-450 CYP2B6; D065731:Cytochrome P-450 CYP2C19; D065727:Cytochrome P-450 CYP2C8; D065729:Cytochrome P-450 CYP2C9; D019389:Cytochrome P-450 CYP2D6 / Q000378:metabolism; D065690:Cytochrome P-450 CYP2D6 Inhibitors; D051544:Cytochrome P-450 CYP3A / Q000378:metabolism; D065692:Cytochrome P-450 CYP3A Inhibitors; D065607:Cytochrome P-450 Enzyme Inhibitors; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D029774:Gynostemma; D041743:Herb-Drug Interactions; D006801:Humans; D008658:Inactivation, Metabolic; D020128:Inhibitory Concentration 50; D008862:Microsomes, Liver / Q000187:drug effects / Q000201:enzymology*; D010936:Plant Extracts / Q000494:pharmacology
chemical_list: D065609:Cytochrome P-450 CYP1A2 Inhibitors; D065690:Cytochrome P-450 CYP2D6 Inhibitors; D065692:Cytochrome P-450 CYP3A Inhibitors; D065607:Cytochrome P-450 Enzyme Inhibitors; D010936:Plant Extracts; C474918:gypenoside; D003577:Cytochrome P-450 Enzyme System; C450260:CYP2C9 protein, human; D065729:Cytochrome P-450 CYP2C9; D001189:Aryl Hydrocarbon Hydroxylases; C504573:CYP1A2 protein, human; C585599:CYP2B6 protein, human; C045793:CYP2C19 protein, human; C450259:CYP2C8 protein, human; D019388:Cytochrome P-450 CYP1A2; D065702:Cytochrome P-450 CYP2B6; D065731:Cytochrome P-450 CYP2C19; D065727:Cytochrome P-450 CYP2C8; D019389:Cytochrome P-450 CYP2D6; D051544:Cytochrome P-450 CYP3A; C510163:CYP3A4 protein, human