银杏内酯B对体外培养神经干细胞内HIF-1α及PI3K/Akt信号通路的影响

Effects of ginkgolide B on the expression of hypoxia-inducible factor-1 alpha( HIF-1α) and PI3K/Akt signal pathway on the neural stem cells in vitro

目的探讨银杏内酯B(GKB)对体外培养神经干细胞(NSCs)内低氧诱导因子-1α(HIF-1α)及磷脂酰肌醇-3激酶(PI3K)/Akt信号通路表达的影响。方法在建立谷氨酸对神经干细胞损伤的模型基础上,给予银杏内酯B、PI3K/Akt特异性抑制剂wortmannin进行干预,将实验分为两大组:即正常细胞组、谷氨酸损伤组,各组下又分为4个小组:(1)GKB组;(2)对照组;(3)wortmannin+GKB组;(4)wortmannin组。采用Western blot印迹来检测各组NSCs中HIF-1α、Akt、磷酸化Akt(p-Akt)蛋白水平的表达。结果无论正常细胞组还是谷氨酸损伤细胞组,NSCs经GKB处理后HIF-1α、p-Akt表达均较对照组明显增高,差异有统计学意义(P<0.05);经wortmannin处理后HIF-1α、p-Akt蛋白表达受抑制,较对照组明显减弱(P<0.05);wortmannin+GKB组和wortmannin组比较,HIF-1α、p-Akt表达上调,差异有统计学意义(P<0.05)。NSCs经谷氨酸处理后,HIF-1α、p-Akt表达较未受损的NSCs表达增强(P<0.05)。结论银杏内酯B是神经干细胞保护作用机制之一,可能与激活PI3K/Akt信号通路、进一步上调HIF-1α表达有关。

Objective To investigate the effects of ginkgolide B on the expression of hypoxia-inducible factor-1 alpha（HIF-1α）and phosphatidylinositol-3-kinase（PI3K）/Akt signal pathway on the neural stem ceils in vitro. Methods Setting up the model of glutaminic acid damaging the neural stem cell, after ginkgolide B, PI3K/Akt inhibitor wortmannin were used to intervene, the cultured cells were divided into two major groups, the normal group and the glutamate injury group, each group was subdivided into four groups ： （ 1 ） GKB group ; （ 2 ） the control group ; （ 3 ） wortmannin ＋ GKB group ; （4） wortmannin group. The expression of HIF-1α, Akt and phosphorylated Akt at protein level were measured by Western blot. Results Both normal NSCs and NSCs injuried by glutamate, the protein expression of HIF-1α,p-Akt in GKB group were significantly increased compared with the control group after treatment by ginkgolide B, the difference was statistically significant （ P 〈 0.05 ） ; the protein expression of HIF-1α, p-Akt were significantly decreased after the treatment of wortmannin compared the normal group and the glutamate injury group, with the non-treatment group （P 〈 0. 05 ） ;the expression of HIF-1α, p-Akt were significantly improved in wortmannin ＋ GKB group compared with the wortmannin group, the difference was statistically significant（P 〈 0.05 ）. Compared with normal cells, the expression of HIF-1α and p-Akt significantly increased in NSCs after treated with glutamic （ P 〈0. 05 ）. Conclusions Ginkgolide B on one of the protective mechanisms of neural stem ceils may be associated with activatting of PI3K/Akt signaling pathway, and further increase HIF-1α expression.