Tian X, Cheng ZY, He J, Jia LJ, Qiao HL. Concentration-dependent inhibitory effects of baicalin on the metabolism of dextromethorphan, a dual probe of CYP2D and CYP3A, in rats.
Chem Biol Interact 2013;
203:522-9. [PMID:
23458730 DOI:
10.1016/j.cbi.2013.02.005]
[Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2012] [Revised: 01/31/2013] [Accepted: 02/18/2013] [Indexed: 02/04/2023]
Abstract
Baicalin has been shown to possess many pharmacological effects, including antiviral, antioxidant, anti-cancer and anti-inflammatory properties. In the current study, we reveal the inhibitory effects of baicalin on the metabolism of dextromethorphan (DXM), a dual probe substrate of CYP2D and CYP3A, in rats. Lineweaver-Burk plots demonstrated that baicalin inhibited the activities of CYP2D and CYP3A in a non-competitive manner in rat liver microsomes (RLMs). Concomitant administration of baicalin (0.90 g/kg, i.v.) and DXM (10 mg/kg, i.v.) increased the maximum drug concentration (C(max)) (37%) and the area under concentration-time curve (AUC) (42%) and decreased the clearance (CL) (27%) of DXM in a randomised, crossover study in rats (P < 0.01). The change in the AUC of DXM was significantly correlated with the C(max) and AUC of baicalin (P < 0.05). The inhibitory effects of multiple doses of baicalin (0.90 g/kg, i.v., 12 days) on the metabolism of DXM were similar to those observed following a single dose in rats. The activity of CYP3A in excised liver samples from rats following multiple baicalin treatment was significantly decreased compared to that of the control group (P < 0.05), whereas multiple doses of baicalin had no obvious effect on the activity of CYP2D. Taken together, these data demonstrate that baicalin inhibits the metabolism of DXM in a concentration-dependent manner in rats, possibly through inhibiting hepatic CYP2D and CYP3A activities.
Collapse