Standardized Salvia miltiorrhiza Extract Suppresses Hepatic Stellate Cell Activation and Attenuates Steatohepatitis Induced by a Methionine-Choline Deficient Diet in Mice

The aim of this study was to examine the effect of standardized extract of Salvia miltiorrhiza (SME) on gene and protein expression of non-alcoholic steatohepatitis (NASH)-related factors in activated human hepatic stellate cells (HSC), and in mice with steatohepatitis induced by a methionine-choline deficient (MCD) diet. Male C57BL/6J mice were placed on an MCD or control diet for 8 weeks and SME (0, 0.1, 0.5 and 1 mg/kg body weight) was administered orally every other day for 4 or 6 weeks. HSCs from the LX-2 cell line were treated with transforming growth factor beta-1 (TGF-beta 1) or TGF-beta 1 plus SME (0.1-10 mu g/mL). To investigate the effect of SME on reactive oxygen species (ROS)-induced condition, LX-2 cells were treated with hydrogen peroxide (H2O2) or H2O2 plus SME (0.1-100 mu g/mL). MCD administration for 12 weeks increased mRNA expression of tumor necrosis factor (TNF-alpha), TGF-beta 1, interleukin-1 beta (IL-1 beta), C-reactive protein (CRP), alpha-smooth muscle actin (alpha-SMA), type I collagen, matrix metalloproteinase-2 (MMP-2) and MMP-9. TGF-beta 1-induced LX-2 cells exhibited similar gene expression patterns. SME treatment significantly reduced the mRNA and protein expression of NASH-related factors in the mouse model and HSCs. Histopathological liver analysis showed improved non-alcoholic fatty liver disease (NAFLD) activity and fibrosis score in SME-treated mice. The in vivo studies showed that SME had a significant effect at low doses. These results suggest that SME might be a potential therapeutic candidate for NAFLD treatment.