Abstract: Objective To explore the dynamic changes of autophagy and its role in oxygen-glucose deprivation (OGD)-induced ischemic injury in primary cultured cortical neurons of mice in vitro. Methods The primary cortical neurons that obtained from postnatal 24 h C57BL/6J mice were cultured for 7 days, and then were divided into six groups (n=6 per group), including normoxia (Nor.), 15, 30, 60, 90 and 120 min OGD/24 h reoxygenation. The effect of OGD treatment on autophagy-related protein levels of Beclin-1 and LC3II/I ration were determined by using Western blot analysis. The colorimetric method of thiazolyl blue tetrazolium bromide (MTT) and the leakage rate of lactate dehydrogenase (LDH) were applied to assess OGD-induced ischemic injury. The autophagy inhibitor Bafilomycin A1 (BafA1, 100 nmol/L) was used to explore the effect of autophagy on OGD-induced ischemic injury of cortical neurons. Results Compared with normoxic group, the levels of autophagy-related protein Beclin-1 and LC3II/I ratio significantly increased with the exposure time of OGD treatment, and the increase of Beclin-1 and LC3II/I ratio reached their peaks at 30 min of OGD treatment (p<0.05). Both of 30 and 60 min OGD treatment could significantly affect the viability and mortality of cortical neurons (p<0.05). In addition, the autophagy inhibitor BafA1 could aggravate 60 min OGD-induced ischemic injury and enhance the LC3II/I ratio (p<0.05). Conclusions These results demonstrated that OGD treatment could induce autophagy in primary cultured cortical neurons, and autophagy may protect cortical neurons against OGD-induced ischemic injury.

Key words: primary cultured cortical neurons, oxygen-glucose deprivation (OGD), autophagy, Bafilomycin A1 (BafA1), ischemic injury