Aim of the study: The present study was designed to investigate the molecular weight (MW), chemical composition and effect of polysaccharide (CS-PS), from the fruiting bodies of cultured Cordyceps sinensis, on immune function and anti-oxidation activity of BALB/c mice exposed to Co-60. Materials and methods: The MW of CS-PS was determined by gel-filtration. The chemical composition of CS-PS was tested by using gas chromatography-mass spectrophotometer (GC-MS). Mice were administered CS-PS with doses of 50, 100 or 200 mg/kg body weight, then exposed to Co-60. The normal control group and irradiated control group were also used. Four days later, lymphocyte proliferation, activity of macrophage phagocytosis, delayed type hypersensitivity (DTH), concentration of malondialdehyde (MDA), total-superoxide dismutase (SOD) enzyme activity, and cytokine expression in serum from the mice were tested. Results: The average molecular weight of CP-PS was 12 kD. The polysaccharide was composed of mannose, rhamnose, arabinose, xylose, glucose and galactose. Lymphocyte proliferation, the activity of macrophage phagocytosis, DTH and total-SOD enzyme activity in the CS-PS groups were significantly enhanced compared to the irradiated control group. Lipid peroxidation level was significantly reduced in the CS-PS groups compared to the irradiated control group. Levels of cytokine IL-4, IL-5 and IL-17 are also affected in the CS-PS groups compared to the irradiated control group. Conclusions: CS-PS, a heteropolysaccharide, enhances immunity activity in mice treated by ionizing radiation, through reducing oxidative injury and modulating the secretion of cytokine IL-4, IL-5 and IL-17. (C) 2011 Elsevier B.V. All rights reserved.
