Standardized Salvia miltiorrhiza Extract as a Therapeutic Candidate for the Treatment and Prevention of Non-alcoholic Steatohepatitis

Abstract

Non-alcoholic fatty liver disease (NAFLD) refers to a broad spectrum of liver damage, which ranges from simple steatosis or intracellular triglyceride accumulation to inflammation (non-alcoholic steatohepatitis

NASH) fibrosis and cirrhosis. The aim of this study was to investigate the effect of standardized extract of Salvia miltiorrhiza (SME) on gene and protein expression of 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 β-1 (TGF-β1) or TGF-β1 plus SME (0.1–10 μg/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 μg/mL). MCD administration for 12 weeks increased mRNA expression of tumor necrosis factor (TNF-α), TGF-β1, interleukin-1β (IL-1β), C-reactive protein (CRP), α-smooth muscle actin (α-SMA), type I collagen, matrix metalloproteinase-2 (MMP-2) and MMP-9. TGF-β1-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 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 treatment and prevention of NAFLD.