Hepatoprotection of Gentiana scabra Extract and Polyphenols in Liver of Carbon Tetrachloride-Intoxicated Mice

In traditional Chinese medicine, the rhizomes of Gentiana scabra are used to treat hepatitis, stomatitis, and inflammatory diseases. This study aimed to examine the protective effects of G. scabra aqueous extract (GS) and polyphenols in liver of CCl4-intoxicated mice. Antioxidant activities of GS were also evaluated. Results showed that GS exhibited anti-lipid peroxidation, 2,2-diphenyl-1-picrylhydrazyl, and superoxide radical scavenging activities with IC50 values of 45.84, 183.38, and 56.25 mu g/mL, respectively. High-performance liquid chromatography analysis revealed that the major polyphenolic constituents of GS were kaempferol, ellagic acid, and quercetin. Daily oral administration of 500 mg/kg GS (GS500) and 1000 mg/kg GS (GS1000) significantly prevented the elevation of glutamic pyruvic transaminase and thiobarbituric acid reactive substances levels, while enhancing the levels of antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase) and serum total antioxidant activity in mice with hepatoxicity. At 1000 mg/kg, GS was as effective as 100 mg/kg silymarin in reducing oxidative stress and preventing liver injury. Histopathological studies further confirmed the hepatoprotective activity of OS. Taken together, these results show that the antioxidant activities and polyphenolic compounds (kaempferol, ellagic acid, and quercetin) of GS may have contributed to its hepatoprotective activity in CCl4-intoxicated mice, and its mechanism of action could be mediated through the reduction of oxidative stress in liver tissue.