Abstract: Objective　To study the antioxidant and neuroprotective effects of Codonopsis pilosula polysaccharides (CPP) and its possible mechanism.　Methods　Rice method was used to establish HIBI rat model. Normal saline was given to the sham group and the HIBI group, and corresponding doses of CPP solution were given to the drug groups. The neurological function, cerebral water content of rats, histopathologic changes, apoptosis in the rat hippocampus, the level of lipid peroxide, the expression of antioxidant and neuroprotective proteins were evaluated.　Results　Compared with the model group, the neurological function, cerebral water content and the pathological injury of brain tissue were significantly reduced (P<0.01). The apoptosis rate, expression of Bax, content of LDH and MDA also decreased significantly (P<0.01). Expression of Bcl-2 and activity of SOD were up-regulated (P<0.01). In addition, the expressions of bFGF, BDNF, PSD95, SYP, Nrf2 and HO-1  were significantly up-regulated (P<0.01).  Conclusion　CPP has antioxidant and neuroprotective effects on hypoxic-ischemic brain injury, and its function may be related to mediating Nrf2 signal pathway.

Key words: Hypoxic ischemic brain injury, 　Codonopsis pilosula polysaccharides, 　Nuclear transcription related factor 2, 　Oxidoreductase 1