Yinzhihuang attenuates ANIT-induced intrahepatic cholestasis in rats through upregulation of Mrp2 and Bsep expressions

The treatment of intrahepatic cholestasis has been limited, and development of an effective drug is needed. Clinical studies have shown that Yinzhihuang (YZH), a traditional Chinese decoction, enhances bilirubin clearance. The goal of this study was to determine the protective effect of YZH on experimental intrahepatic cholestasis in young rats and to explore its underlying molecular mechanisms. Intrahepatic cholestasis in rats was induced by α-naphthylisothiocyanate (ANIT) on days 1 and 8. The rats received YZH, ursodeoxycholic acid (UDCA), or vehicle for 9 d and were killed on either day 3 or day 10. Serum biomarkers, liver histology, and the distribution of protein and mRNA expression of Mrp2 and Bsep were analyzed. YZH treatment resulted in decreased levels of serum biomarkers except γ-glutamyl transpeptidase, attenuated liver histological injuries, increased protein expressions of Mrp2 and Bsep, and upregulated expressions of Mrp2 and Bsep mRNAs. The effects of YZH on serum biomarkers (aminotransferase, alanine aminotransferase, and direct bilirubin), liver histology, and Mrp2 mRNA expressions were significantly greater and earlier than those of UDCA. Our results suggest that YZH has protective effect against ANIT-induced intrahepatic cholestasis in rats, through upregulation of Mrp2 and Bsep expressions.