Protective effect of EGb761 against Aβ1-42 -induced SHSY5Y cells injury and blood-brain barrier disruption via regulating Akt/Nrf2 signaling pathway

Abstract

Purpose: Alzheimer’s disease (AD) is a common disease in the world caused by deposition in the brain parenchyma, accumulation of beta amyloid which leads to the blood brain barrier (BBB) disruption. Regardless of enough progress in the treatment of AD, the principal mechanism of BBB injury is yet not clear.Methods: In this study we examined the impact of EGb761on Aβ 1-42-induced SH-SY5Y cells in vitro model of AD. Cell viability was assessed by using MTT assay, flow cytometry was used to check the rate of cell apoptosis, ROS generation and BBB leakage was assessed by measuring the level of fluorescence in Aβ-induced SH-SY5Y cells using a reactive oxygen species kit assay and BBB permeability assay, and mRNA levels of Bax, Bcl-2, caspase-3 was measured by using RT-qPCR. Furthermore, western blot analysis was used to measure the protein expressions of Akt, Nrf2 and HO-1 in Aβ 1-42-induced SH-SY5Y cells.Results: The effect of EGb761 was investigated on the cell apoptosis induced by Aβ 1-42 andgeneration of ROS and we found that EGb761 plays a protective role against cell injury induced by Aβ 1-42. Cell apoptosis and ROS generation in SH-SY5Y cells decreased significantly with the treatment of EGb761. Furthermore, BBB permeability reduced considerably when the cells treated with EGb761 and the expression levels of Caspase-3 and Bax decreased while that of Bcl-2 were markedly increased in the Aβ 1-42-induced SH-SY5Y cells. Also, an increased in expression levels of p-Akt, Nrf2 (nucleus) and HO-1 was observed with the treatment of EGb761 in Aβ 1-42-induced SH-SY5Y cells.Conclusion: It can be concluded from these results that EGb761 could play a protective role byinhibiting apoptosis and protect Aβ 1-42-induced cell injury in vitro model of AD via activating Akt/Nrf2signaling pathway. Our study suggested that EGb761 might be a therapeutic agent for the preventionand treatment of AD.