Diterpene ginkgolides meglumine injection inhibits oxidative stress induced by oxygen-glucose deprivation by activating Akt/Nrf2 pathway in SH-SY5Y cells / 中国药理学与毒理学杂志

ABSTRACT

OBJECTIVE To investigate the protective effects and mechanism of diterpene ginkgolides meglumine injection (DGMI) against oxidative stress induced by oxygen-glucose deprivation (OGD) in SH-SY5Y cells. METHODS SH-SY5Y cells were divided into five groups normal control, model control (OGD group) and drug(25 mg · L- 1) administration groups including DGMI group, extract of ginkgo biloba leaves injection group (EGBLI) and lactones ginkgo biloba injection group (LGBI). The cells suffered from oxygen-glucose deprivation (OGD) for 4 h, followed by reoxygenation with drugs for 6 h. Then, cell viabilities were detect using CCK-8 assays, reactive oxygen species (ROS) levels using fluorescence probe DCFH-DA and superoxide dismutase (SOD) activities using WST-1 test. Western blotting was used to detected protein levels of hemeoxygenase-1(HO-1), NAD(P)H, quinone oxidore?ductase l (Nqo1), protein kinase B (Akt), phosphorylated Akt (p-Akt), nuclear factor-E2-related factor2 (Nrf2) and phosphorylated Nrf2 (p-Nrf2). The cells were induced by OGD for 4 h, followed by reoxygen?ation and DGMI for 1 h, combined with different concentrations of PI3K inhibitor (LY294002) (at the final concentration of 12.5, 25 and 50 μmol · L-1) before the protein levels of AKT, p-AKT, Nrf2 and p-Nrf2 were detected by Western blotting. RESULTS SH-SY5Y cells induced by OGD for 4 h resulted in an increase in ROS(P<0.01), but a decrease in cell viabilities(P<0.01), SOD activities(P<0.01), and antioxidant protein levels ( Akt, p-Akt, Nrf2, p-Nrf2, HO-1 and Nqo1) (P<0.01). Compared with OGD group, treatment with reoxygenation and drugs (DGMI,EGBLI and LGBI respectively) for 6 h resulted in a decrease in ROS (P<0.01), but an increase in cell viabilities, SOD activities and antioxidant protein levels of p-Nrf2, HO-1, Nqo1 and p-Akt(P<0.05,P<0.01). DGMI group showed the best efficiently. Moreover, after OGD for 4 h, compared with DGMI group, combining reoxygenation and DGMI with LY294002 for 1 h resulted in a concentration-dependent inhibition of the protein levels of p-AKT and p-Nrf2(P<0.01). CONCLUSION DGMI 25 mg · L-1 can inhibit oxidative stress in SH-SY5Y cells induced by OGD by increasing the activity and expression of Nrf2 through PI3K/Akt pathway, which may be one of the mechanisms by which DGMI protects neurons from stroke.