Salvianolic acid, a major water-soluble compound extracted from Salvia miltiorrhiza (Danshen), is widely studied for its potential hepatoprotective effects. Scientific research, primarily from in vitro and animal studies, suggests that salvianolic acid exhibits antioxidant, anti-inflammatory, and anti-fibrotic activities in the liver. These properties are believed to help protect hepatocytes from damage caused by oxidative stress, toxins, and inflammation, which are key factors in various liver diseases such as hepatitis, non-alcoholic fatty liver disease (NAFLD), and hepatic fibrosis.

Specifically, salvianolic acid has been shown to enhance the activity of endogenous antioxidant enzymes (such as superoxide dismutase and glutathione peroxidase), reduce lipid peroxidation, and inhibit pro-inflammatory cytokines like TNF-α and IL-6 in liver tissue. Some studies also demonstrate that salvianolic acid can attenuate hepatic stellate cell activation, a crucial event in the development of liver fibrosis.

However, while the preclinical evidence is promising, there are limited high-quality clinical trials in humans to conclusively establish its efficacy and safety for liver support. Most of the current knowledge derives from laboratory and animal models. Therefore, the evidence is rated as moderate (3/5), acknowledging the strong preclinical foundation but noting the need for further clinical validation.