Evaluation of the hepatoprotective effect of green tea extract and selenium on CCL4-induced fibrosis

SummaryBackground & aimsThis investigation aimed to evaluate the possible hepatoprotective effects of green tea extract and selenium on liver fibrosis in comparison with silymarin and to study the underlying mechanisms.MethodsLiver fibrosis was induced in rats by i.p. injection of CCL4 (3 times a week for 6 weeks in a dose of 25 μl/100 g b.w). Green tea extract (200 mg/kg), selenium (0.945 mg/kg) and silymarin (100 mg/kg) were given orally and daily for 8 weeks (2 weeks before CCL4 and 6 weeks along with CCL4).ResultsCCL4-induced fibrosis as indicated by increased activities of liver enzymes and increased lactate dehydrogenase (LDH) activity is an indicator of cell death. It also elevated serum nitric oxide (NO), inflammatory mediators like tumor necrosis factor alpha (TNF-α) and liver lipid peroxidation and decreased liver reduced glutathione (GSH) content. It also increased liver collagen fiber percent and caused liver cell damage. On the other hand, green tea and selenium reduced these changes and improved the pathological effects caused by CCL4. Both drugs’ effects were similar to silymarin hepatoprotective effects but they cause greater reduction of collagen fiber percent than silymarin.ConclusionsFindings of the present study suggest that green tea extract and selenium have protective effects similar in most aspects to silymarin via anti-inflammatory and antioxidant effects. In addition, their antifibrotic effect was stronger than that of silymarin. So both natural products may be used as adjunctive therapy in liver fibrosis.