Total Flavonoids from Flowers of Abelmoschus manihot for Amelioration of α-naphthylisothiocyanate-induced Cholestasis by Regulating Expression of Transporters

Abstract

ObjectiveTo explore the molecular mechanisms of the total flavonoids extracted from the flowers of Abelmoschus manihot (TFA) against α-naphthylisothiocyanate (ANIT)-induced cholestasis. MethodsThe hepatoprotective activities of TFA (125, 250 and 500 mg/kg) were investigated on ANIT-induced cholestatic liver injury in rats. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL), total bile acid (TBA), and bile flow were measured to evaluate the protective effect of TFA. Furthermore, the hepatic mRNA and protein levels of transports, multidrug resistance-associated protein 2 (MRP2), bile salt export pump (BSEP), and Na+-taurocholate cotransporting polypeptide (NTCP) were investigated to elucidate the protective mechanisms of TFA against ANIT-induced cholestasis. ResultsPretreatment of TFA significantly and dose-dependently decreased the ANIT-induced elevation of serum ALT, AST, TBIL, and TBA levels and increased the ANIT-induced suppression of bile flow. Moreover, TFA was found to increase the expression of liver MRP2, BSEP, and NTCP in both protein and mRNA levels in ANIT-induced liver injury in rats with cholestasis. ConclusionTFA exerts a therapeutic effect on ANIT-induced liver injury in rats with cholestasis, possibly through regulating the expressions of hepatic transporters.