Inhibitory Effects of Deoxyschizandrin on P-glycoprotein in Vitro and in Vivo / 医药导报

ABSTRACT

Objective To investigate the influence of deoxyschizandrin (Deo) on P-glycoprotein (P-gp).Methods The effect of P-gp on Deo (20,40,80 μg·mL-1) was studied in the Caco-2 cell model in vitro,and the apparent permeability coefficient (Papp) of Deo (20-160 μg·mL-1) on a P-gp substrate,rhodamine123 or cyclosporine A,was calculated.Healthy male Sprague-Dawley rats were randomly divided into five groups:blank control group,verapamil group,low-,medium-and high-dose Deo group (8 rats in each group).Rats in the low-,medium-and high-dose Deo group were intragastrically administered once daily with Deo at 8,16 and 32 mg·kg-1 for 3 consecutive days,while rats similarly received gavagewith verapamil (4 mg·kg-1) in the verapamil group and equal volume of purified water in the blank control group.Thirty minutes after the rats were treated with their respective drugs,rhodamine123 (5 mg· kg-1) was orally administrated.Then the pharmacokinetic profiles of rhodamine 123 were analyzed to evaluate the inhibitory ability of Deo on P-gp in vivo.Results The bidirectional transport rates of Deo (20,40,80 μg·mL-1) were similar,with non-selectivity.Deo (20-160 pg·mL-1)significantly inhibited the basolateral→apical(BL→AP) directional transports of rhodamine 123 and cyclosporine A in Caco-2 cell model (P ＜ 0.05) in a concentration-dependent manner.And Deo (8-32 mg· kg-1) also dose-dependently decreased the peak concentrations (Cm.) and the area under the plasma concentration-time curve (AUC0-t) of Rho123.Conclusion Deo can inhibit P-gp in vitro and in vivo,but it is not a P-gp substrate.