Protective effect of a polysaccharide from Rhizoma Atractylodis Macrocephalae on acute liver injury in mice.

A homogeneous polysaccharide was isolated and purified from Rhizoma Atractylodis Macrocephalae (RAM) and named PRAM2. Its average molecular weight was 19.6×10(3)Da and it was composed of rhamnose, xylose, arabinose, glucose, mannose and galactose in a ratio of 1: 1.3: 1.5: 1.8: 2.1: 3.2. In vitro experiments confirmed that PRAM2 presented an obvious effect to scavenge 1,1-diphenyl-2-picrylhydrazyl radical 2,2-diphenyl-1-(2,4,6-trinitrophenyl) (DPPH), superoxide anion and hydroxyl radical. In vivo experiments confirmed that PRAM2 could reduce the liver weight, liver index, aspartate transaminase (AST) and alanine aminotransferase (ALT) activities in the serum; meanwhile, PRAM2 could significantly reduce nitric oxide synthase (NOS) activity, and nitric oxide (NO) and malonaldehyde (MDA) contents in the liver tissues, and increase superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities. These results suggest that PRAM2 has a significant in vitro antioxidant activity and a protective effect on CCl4-induced liver injury in mice; the protective effect may be related to its anti-oxidation, its inhibition of NOS activity and NO level and its reduction of the production of free radicals.