Anti-oxidative effect of glycyrrhizin on acute andchronic CCl4-induced liver injuries

Abstract

Aims The aim of this study was to investigate the anti-oxidativeactivity of Glycyrrhizin (GL), the major bioactive triterpene glycosideof licorice (Glycyrrhizza glabra L.), in its protection against acute andchronic CCl4-induced liver injuries.Methods A single dose of 50% CCl4solution 1.5 ml/kg body weightwas injected intraperitoneally (i.p.) in Sprague-Dawley rats to induceacute liver injury. Two doses of GL (200 mg/kg, i.p.) were adminis-trated to the rats at 1 and 12 h later. Serum and liver samples werecollected at 24 h and hepatotoxicity was evaluated by the serum activ-ity of alanine aminotransferase (ALT) and liver histopathology. Liveroxidized and reduced forms of glutathione (GSSG and GSH) con-tents and lipid peroxidation level in the hepatic tissues were assessed.For the chronic model of liver injury, 2.25 ml/kg body weight of CCl4solution (1:5) was administrated to rats three times per week bygastric gavage. GL (200 mg/kg, i.p.) were administrated to rats oncedaily. Serum and liver samples were collected at the 2th, 4th, 6th and8th weeks post CCl4administration for the analysis of histopathol-ogy, liver glutathione content, and lipid peroxidation level.Results GL adminstration normalized the rise of serum ALT levelin CCl4treated rats. It improved the necrotic damages induced byacute CCl4 insult and the fibrotic change induced by chronic CCl4injury. The ratio of GSSG and GSH and the level lipid peroxidationin the livers of rats treated with CCl4were decreased with the admin-istration of GL.Conclusions GL protects rats against acute and chronic CCl4-induced liver injuries. This is associated with the potent anti-oxidative effect of GL. GL could be a promising agent for the treatmentof drug-induced liver toxicity, and possibly other acute or chronic liverinjuries with the involvement of oxidative stress.