Salvianolate lyophilized injection induced autophagy against neuronal apoptosis through the Akt/mTOR pathway in Neuro-2a cells

Abstract

Background: Stroke remains a worldwide health problem. Salvianolate lyophilized injection (SLI) is one of the most widely-used in clinics in China for treating stroke. Our previous research found that SLI protects against stroke by inhibiting oxidative stress and inflammation. Whether SLI has other biological effects on stroke remains unknown. Methods: Neuro-2a (N2a) cells were treated with SLI (10, 25, 50μg/ml) and exposed to oxygen-glucose deprivation/reoxygenation (OGD/R) as an in vitro model of ischemic stroke. Then, cell apoptosis was assessed using flow cytometry, apoptosis and autophagy related proteins were investigated by western blotting. Autophagy inhibitor 3-methyladenine (3-MA) pretreatment was used to detect the apoptosis effect of SLI on N2a cells. Results: In this work, we verified that SLI promoted cell proliferation, inhibited cell injury and apoptosis in OGD/R-induced N2a cells. The increase the expression of autophagy markers LC3 and Beclin-1, and decrease autophagy substrate protein p62 demonstrated the induction of autophagy by SLI. Additionally, we found that SLI activation of autophagy significantly preceded inhibition of apoptosis in N2a. Pretreatment with autophagy inhibitor 3-MA could antagonize the protective effect of SLI on inhibiting apoptosis, which may be related to the Akt/mTOR signalling pathway. Conclusions: The present study indicated that SLI has potential as a novel therapy for ischemic stroke, and its possible mechanism is to induced autophagy and inhibit apoptosis through blocking Akt/mTOR signaling pathway in OGD/R-induced N2a cells, providing new insights into the mechanism of SLI in the treatment of stroke.