Effect of salvianolic acid B on hepatocyte apoptosis in rats with nonalcoholic steatohepatitis

Objective To investigate the effect of salvianolic acid B on hepatocyte apoptosis in rats with nonalcoholic steatohepatitis (NASH) and the efficacy of salvianolic acid B in the treatment of NASH. Methods Sixty clean male SD rats were randomly divided into control group, NASH model group, and salvianolic acid B treatment group, with 20 rats in each group. The control group was fed with normal diet, while the other two groups with high-fat diet for 12 continuous weeks to establish a NASH model. From week 13, rats in the treatment group were gavaged with 1 mg / ml salvianolic acid B (20 ml / kg b. w. daily) ; while the model group with distilled water (20 ml / kg b. w daily) . After 12 weeks of treatment, the rats were sacrificed; blood and hepatic tissues were sampled, liver index (liver weight / body weight) calculated, serum levels of alanine aminotransferase (ALT) , aspartate aminotransferase (AST) , triglycerides (TG) , and total cholesterol (TC) measured, and the pathologic changes in hepatic tissues observed. The protein expression of caspase-3 and cytochrome C (Cyt C) in hepatic tissues was measured by immunohistochemical methods. The mRNA expression of p53, Bax, and Bcl-2 in hepatic tissues was measured by RT-PCR. Results Compared with the normal group, the model group showed higher liver index and serum levels of ALT, AST, TG, and TC and more obvious inflammation of hepatic tissues; the protein expression of Cyt C and caspase-3 was significantly increased (P < 0. 01 for both) ; the mRNA expression of Bcl-2 was significantly reduced (P < 0. 01) , while that of Bax and p53 was significantly increased (P < 0. 01 for both) . Compared with the model group, the treatment group showed alleviated inflammation and reduced liver index and serum levels of ALT, AST, TG, and TC; the protein expression of Cyt C and caspase-3 was significantly reduced (P < 0. 01 for both) ; Bcl-2 mRNA expression was significantly increased (P < 0. 05) , p53 mRNA expression significantly reduced (P < 0. 05) , and Bax mRNA expression also significantly reduced (P < 0. 01) . Conclusion Salvianolic acid B can inhibit hepatocyte apoptosis and treat NASH by regulating the mRNA expression of Bcl-2, p53, and Bax and reducing the protein expression of Cyt C and caspase-3.