RESUMO
Ionizing radiation induces the production of reactive oxygen species [ROS], which play an important causative role in cell death. The aim of this study was to investigate the protective effects of sulfated derivatives of neutral polysaccharides extracted from Auricularia auricular [SNAAP]. Whole blood samples from healthy donors treated with SNAAP at different concentrations [20, 60, 100 microg/mL] were exposed to various doses of X-rays. Wistar rat spleen lymphocytes, in cultures, were treated with SNAAP at different concentrations [20, 60, 100 microg/mL] in the presence p.o 12 hours prior to 8 Gy gamma radiation exposure. Animals were administered with SNAAP at doses of 50, 100 or 200 mg/kg body weight d p.o 7 days prior to sub-lethal doses [6 Gy] of whole body gamma radiation exposure. SNAAP is an effective radio protector against X-ray radiation induced in vitro cellular damage in human peripheral blood. Furthermore, to support this finding the effect of SNAAP on a rat's spleen lymphocytes, when cultured and examined 24 hours after exposure to 8 Gy gamma of radiation, demonstrated the effect of polysaccharides on a rat's spleen lymphocytes, pretreated by the SNAAP, can increase the cell viability compared with irradiated group at a concentration of 20, 60 and 100 microg/mL. Likewise, this radiation-induced therapy decreased each mouse's body weight and effectively stimulated the immune system of all radiated mice. Moreover, when induced by Co60, the SNAAP decreased the level of malondialdehyde [MDA] and increased the myeloperoxidase [MPO] and the glutathione peroxidase [GSH-Px] activity in the whole blood supply of the irradiated mice. These encouraging results support further research into the clinical pharmacology of SNAAP as a novel agent for human radiation protection