IGF-1通过PI3K/Akt信号通路诱导神经干细胞向神经元分化  

Insulin-like grow th factor-1 induces neural stem cells to differentiate into neurons via PI3K/Akt signaling pathw ay

作　　者：朱裕华[1] 袁红花[2] 吴连连[2] 胡安康[1] 陈仁金[1] 朱孝荣[1] 

机构地区：[1]徐州医学院实验动物中心,江苏徐州221002 [2]徐州医学院神经生物学教研室,江苏徐州221002

出　　处：《山东大学学报（医学版）》2014年第3期11-15,共5页Journal of Shandong University:Health Sciences

基　　金：国家自然科学基金(31172171);江苏省自然科学基金(BK2011209);江苏省青年基金(BK2012138)

摘　　要：目的观察胰岛素样生长因子-1(IGF-1)对体外培养神经干细胞(NSCs)向神经元分化的影响,并探讨PI3K/Akt信号通路与之的关系。方法取新生C57BL/6J小鼠海马组织,分离、培养NSCs,将细胞团吹散,以1×104个/mL密度接种于24孔板,分别加入终浓度100 ng/mL的IGF-1和50μmol/L的PI3K/Akt通路特异抑制剂LY294002,根据处理的情况,将细胞分为IGF-1组、正常对照组、LY组和IGF-1+LY组。βⅢTubulin免疫荧光细胞化学染色法检测NSCs分化为神经元的情况,DAPI染核计细胞总数;p-Akt免疫荧光染色检测各组细胞Akt磷酸化的情况;Western blotting法检测Akt和p-Akt蛋白的表达量,并对各组进行比较。结果 IGF-1组NSCs向神经元分化的比率显著高于对照组、LY组和IGF-1+LY组(P均<0.05);免疫荧光染色结果显示,IGF-1组Akt磷酸化水平显著高于对照组、LY组和IGF-1+LY组(P均<0.05);Western blotting结果显示,IGF-1促进Akt磷酸化,LY294002抑制Akt的磷酸化。结论 IGF-1诱导Akt的磷酸化,从而激活PI3K/Akt信号通路,促进NSCs向神经元分化。Objective To observe the effect of insulin-like growth factor-I （ IGF-1 ） on the differentiation of neural stem cells（NSCs） cultured in vitro into neurons, and to explore its relationship with PI3K/Akt signaling pathway. Methods Neonatal hippocampus tissues were isolated from C57BL/6J mice to obtain NSCs cultures. The NSCs were treated with IGF-1 and the inhibitor（ LY294002 ） at final concentrations of 100 ng/mL and 50 p^mol/L, respectively. The NSCs were divided into four groups： IGF-1 group, normal control group, LY group and IGF-1 ＋ LY group. 1311I Tubulin immunofluorescence staining was used to detect the differentiation of NSCs into neurons and DAPI nuclear staining was applied to quantify cell numbers ; p-Akt immunofluorescnce staining was adopted to detect the expression of phosphoryla- ted Akt （p-Akt） in each group; Western blotting was used to detect the expressions of Akt and p-Akt proteins, followed by the comparison among each group. Results IGF-1 could promote the differentiation of NSCs into neurons and the differentiation rate was significantly higher than that of normal control group, LY group and IGF-1 ＋ LY group（ all P 〈 0.05 ） ; immunofluorescence staining results showed that the expression level of p-Akt in IGF-1 group was significantly higher than those of normal control group, LY group and IGF-1 ＋ LY group （ all P 〈 0.05 ） ; Western blotting results showed that IGF-1 promoted the phosphorylation of Akt, while LY294002 inhibited Akt phosphorylation. Conclusion IGF-1 induces Akt hosphorylation via activating PI3K/Akt signaling pathway and promotes NSCs differentiating into neurons.

关 键 词：胰岛素样生长因子1 PI3K AKT信号通路 神经干细胞 分化 小鼠 C57BL 6J 

分 类 号：R34[医药卫生—基础医学]