Protective Effects of Polydatin from Polygonum cuspidatum against Carbon Tetrachloride-Induced Liver Injury in Mice

Polydatin is one of main compounds in Polygonum cuspidatum , a plant with both medicinal and nutritional value. The possible hepatoprotective effects of polydatin on acute liver injury mice induced by carbon tetrachloride (CCl 4 ) and the mechanisms involved were investigated. Intraperitoneal injection of CCl 4 (50 µl/kg) resulted in a significant increase in the levels of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT) and hepatic malondialdehyde (MDA), also a marked enhancement in the expression of hepatic tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS) and nuclearfactor-kappa B (NF-κB). On the other hand, decreased glutathione (GSH) content and activities of glutathione transferase (GST), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) were observed following CCl 4 exposure. Nevertheless, all of these phenotypes were evidently reversed by preadministration of polydatin for 5 continuous days. The mRNA and protein expression levels of hepatic growth factor-beta1 (TGF-β 1 ) were enhanced further by polydatin. These results suggest that polydatin protects mice against CCl 4 -induced liver injury through antioxidant stress and antiinflammatory effects. Polydatin may be an effective hepatoprotective agent and a promising candidate for the treatment of oxidative stress- and inflammation-related diseases.