Ginsan activated the antioxidant defense systems in irradiated mice

Ginsan, a polysaccharide extracted from Panax ginseng, has hematopoietic activity and is also known as a good biological-response modifier. In this investigation, we studied the effects of ginsan on the γ-radiation induced alterations of some antioxidant systems in spleen of Balb/c mice. There are many data that irradiation induces Reactive Oxygen Species (ROS), which plays an important causative role in radiation damage of cell. The level of ROS in cells is regulated by enzymatic and nonenzymatic antioxidant systems. The most powerful ones among them are superoxide dismutases (SODs) catalyzing the dismutation of superoxide anion radical o2 to H2O2, catalase deactivating h-2O2 and reduced glutathion (GSH) detoxifying H2O2 and other ROS> At the 5th day after sublethal whole body irradiation, splenocytes of irradiated mice expressed only marginally increased levels of Mn-SOD, however, Cu/Zn-SOD, catalase, thioredoxine reductase (TR) and thioredoxine (TRX) mRNA (135% increase compared to control), however, the combination of irradiation with ginsan increased the SODs and GPX production more effectively. In addition to the above results, we obtained the similar data of protein expression. The enzyme activities of SOD, catalase, and GPX of ginsan-treated and irradiated mice were significantly enhanced by 140, 115, 126% respectively, compared with those of irradiated mice. Based on these results, we propose that the induction of antioxidant enzymes of ginsan is at least in part due to its capacity to protect against radiation