Objective: To explore the effects and protective mechanisms of the traditional Chinese medicine complex nao yi-an granule
(NYA) on the neural stem cells (NSCs) after
hypoxia injury. Methods: The cultured hippocampal neural stem cells (NSCs) were taken from the newborn Sprague-Dawley (SD) rats at 3~5 days, the NSCs were cultured at 37℃ in 95%N2 and 5%CO2 for 6 h to make the cells hypoxia injuried; The apoptosis was studied with the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end-labeling (TUNEL) method, p38 MAPK activity in the NSCs was analysed after hypoxia injury with immunoprecipitation/kinase assay/Western blot. Results: Apoptosis was induced by hypoxia injury in the NSCs, NYA serum can promote the NSCs survival and inhibit the apoptosis; The activation of p38 was increased after hypoxia injury, the p38 activity in NYA serum group was significantly lower than the model group and normal-serum group (P<0.01). Conclusions: NYA serum can protect NSCs after hypoxia injury, inhibiting the hypoxia-stimulated p38MAPK signaling transduction pathway may be one of the neuroprotective mechanisms.