Immunoenhancement and antioxidative damage effects of Polygonum Cillinerve polysaccharide on RAW264.7 cells

The effects of Polygonum Cillinerve polysaccharide (PCP) on the immune and antioxidant activity were studied.The effects of PCP on cell proliferation, phagocytic activity, cell uptake, the secretion of NO, iNOS, IL-6, IL-12, CAT and POD, intracellular ROS, cell apoptosis and antioxidative mechanism were measured by MTT, ELISA, fluorescence staining, flow cytometry and western blot.The results showed that PCP had no toxic effect at 31.25-1.95 µg/ml, could improve the uptake of neutral red and fluorescein isothiocyanate-labelled ovalbumin and promote the release of nitric oxide and nitric oxide synthase. Moreover, PCP also could promote the secretion of IL-6 and IL-12. The damage of RAW264.7 cells induced by hydrogen peroxide was significantly alleviated by PCP at 15.63-0.975 µg/ml. The mechanism of antioxidative damage might be that PCP inhibited the upstream p38 and the phosphorylation of JNK and ERK proteins, and down-regulated caspase 3 and up-regulated the protein expressions of cytochrome C and Bcl-2, finally PCP improved the antioxidative capacity and protected the oxidative damage of cells.These results indicated that PCP had the better immunopotentiation and antioxidative damage activity.