Study of the selenizing Codonopsis pilosula polysaccharides protects RAW264.7 cells from hydrogen peroxide-induced injury

Codonopsis pilosula polysaccharides (CPPS) has been shown to possess a variety of biological activities. In previous study, CPPS was successfully modified to obtain its best selenizing Codonopsis pilosula polysaccharides (sCPPS5). The purpose of this study was to investigate the protective effect of the selenizing derivative of CPPS (sCPPS5) from H2O2-induced oxidative damage in RAW264.7 murine macrophages and the possible mechanism of this protection. Results showed that the sCPPS5 was significantly stronger than that of the corresponding unmodified polysaccharide, CPPS. Meanwhile, sCPPS5 treatment could improve the production of reactive oxygen species (ROS), antioxidant enzyme, MMP, caspases-3 and apoptosis capacity of H2O2-induced RAW264.7 cells. Moreover, the mechanism might be elucidated that sCPPS5 could increase expression level of Nrf2 and its downstream ARE gene battery, promote production of corresponding antioxidative enzymes and protein, and enhance Keap1-Nrf2/ARE signaling pathway to avoid male reproductive dysfunction. Overall, these results showed that sCPPS5 as a potent antioxidant could reduce reproductive oxidative stress damage related to Keap1-Nrf2/ARE pathway.