Ginseng extract and ginsenoside Rb1 attenuate carbon tetrachloride-induced liver fibrosis in rats

BACKGROUND Ginsenosides, the major bioactive compounds in ginseng root, have been found to have antioxidant, immunomodulatory and anti-inflammatory activities. This study investigated the effects of ginsenosides on carbon tetrachloride (CCl4)-induced hepatitis and liver fibrosis in rats. METHODS Male Sprague-Dawley rats were randomly divided into four groups: control, CCl4, CCl4 + 0.5 g/kg Panax ginseng extract and CCl4 + 0.05 g/kg ginsenoside Rb1 groups. The treated groups were orally given Panax ginseng extract or ginsenoside Rb1 two weeks before the induction of liver injury for successive 9 weeks. Liver injury was induced by intraperitoneally injected with 400 ml/l CCl4 at a dose of 0.75 ml/kg body weight weekly for 7 weeks. The control group was intraperitoneally injected with olive oil. RESULTS The pathological results showed that ginsenoside Rb1 decreased hepatic fat deposition (2.65 ± 0.82 vs 3.50 ± 0.75, p <0.05) and Panax ginseng extract lowered hepatic reticular fiber accumulation (1.05 ± 0.44 vs 1.60 ± 0.39, p <0.01) increased by CCl4. Plasma alanine aminotransferase and aspartate aminotransferase activities were increased by CCl4 (p <0.01), and aspartate aminotransferase activity was decreased by Panax ginseng extract at week 9 (p <0.05). Exposure to CCl4 for 7 weeks, the levels of plasma and hepatic triglycerides (p <0.01), hepatic cholesterol (p <0.01), interleukin-1β (p <0.01), prostaglandin E2 (p <0.05), soluble intercellular adhesion molecule-1 (p <0.05), hydroxyproline (p <0.05), matrix metalloproteinase-2 (p <0.05) and tissue inhibitor of metalloproteinase-1 (TIMP-1) (p <0.01) were elevated, however, hepatic interleukin-10 level was lowered (p <0.05). Both Panax ginseng extract and ginsenoside Rb1 decreased plasma and hepatic triglyceride, hepatic prostaglandin E2, hydroxyproline and TIMP-1 levels, and Panax ginseng extract further inhibited interleukin-1β concentrations (p <0.05). CONCLUSIONS Panax ginseng extract and ginsenoside Rb1 attenuate plasma aminotransferase activities and liver inflammation to inhibit CCl4-induced liver fibrosis through down-regulation of hepatic prostaglandin E2 and TIMP-1.