Hepatoprotective activity of chitooligosaccharides against

Chitooligosaccharides (COS) is partially hydrolyzed products of chitosan, which has various biological activities including hepatoprotective activity (Santhosh et al., 2007; Shon et al., 2002).The protective effects of COS on ethanol-induced liver damage were investigated in rats. Liver injury model was established by administration of ethanol to rats. The activities of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST), the contents of malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) in hepatic tissues were measured (Yan et al., 2006). Hepatic histological changes were observed by optical microscope. The increases in the activity of serum ALT and the level of liver lipid peroxidation (2.1-fold and 2.6-fold) induced by ethanol were significantly inhibited by oral administration with 100, 200 mg/kg of COS. Morphological observation further confirmed the hepatoprotective effects of COS. In addition, the suppression of antioxidant enzyme (superoxide dismutase) in the liver of ethanol-intoxicated rats was effectively prevented by administration with COS. Further, COS supplementation prevented the ethanol induced cleave of poly (ADP-ribose) polymerase (PARP). It can be concluded the COS had protective effects against liver damage induced by ethanol. Keywords: Chitooligosaccharides; Ethanol; Hepatoprotectio