Protective effect and mechanism of ginsenoside Rg1 on carbon tetrachloride-induced acute liver injury

Liver injury is a common pathological state in various types of liver disease; severe or persistent liver damage is the basis of hepatic failure. Ginsenoside Rg1 (Rg1), one of the primary active ingredients of ginseng, has been reported to reduce concanalin A-induced hepatitis and protect against lipopolysaccharide-and galactosamine-induced liver injury. However, the underlying protective mechanism of Rg1 in acute liver injury remains unclear. In the present study, a carbon tetrachloride (CCl4)-induced acute liver injury model was established, and the protective effect of Rg1 on CCl4-induced acute liver injury was demonstrated in cell culture and animal experimental systems. Further investigation of the mechanisms demonstrated that pretreatment with Rg1 reduced elevated levels of alanine aminotransferase and aspartate amino-transferase, enhanced the antioxidant activity of superoxide dismutase (SOD) and decreased malondialdehyde (MDA) content. Experiments in vitro demonstrated that Rg1 decreased p65 expression and inhibited nuclear factor (NF)-kappa B activity. In addition to the effect of Rg1, an NF-kappa B inhibitor promoted cell survival, enhanced SOD activity and reduced MDA level. It was observed through in vivo experiments that pretreatment with Rg1 inhibited NF-kappa B expression and activity in Kupffer cells and reduced the serum levels of tumor necrosis factor-alpha and interleukin-6. In conclusion, the results of the present study indicated that pretreatment with Rg1 may rescue CCl4-induced acute liver injury in vivo and in vitro through inhibition of NF-kappa B activity, to restore the anti-oxidative defense system and down-regulate pro-inflammatory signaling pathways. The present observations provide a theoretical foundation for the clinical application of Rg1 therapy in acute liver injury.