脑源性神经营养因子诱导缺氧神经干细胞分化的作用研究

目的探讨脑源性神经营养因子(brain derived neurotrophic factor,BDNF)诱导经缺氧培养的大鼠胚胎大脑神经干细胞分化作用。方法将体外培养至第2代的神经干细胞分为3组:对照组(正常培养)、缺氧组(缺氧培养)和BDNF组(缺氧培养同时加入BDNF),分别培养36h后,改变培养条件令细胞分化24、48、72h,RT-PCR测定各组bcl-2、bax、nse、nne、gfap的mRNA水平,通过Western blot检测培养48h后的各基因表达。结果与缺氧组比较,BDNF组凋亡基因48hbcl-2表达明显增高,48、72hbax表达明显降低,差异有统计学意义(P<0.05);分化基因在细胞分化24hnse、nne表达明显升高,gfap表达明显降低,48hnse表达明显升高,gfap明显降低,差异有统计学意义(P<0.01)。结论缺氧可引起神经干细胞向神经胶质细胞分化的增殖,BDNF具有诱导神经干细胞向神经元分化的功能。

Role of brain derived neurotrophic factor in inducing differentiation of hypoxia neural stem cells

Objective To study the role of brain derived neurotrophic factor(BDNF) in inducing differentiation of hypoxia neural stem cells.Methods Neural stem cells cultured in vitro to the second generation were divided into control group(normal culture),hypoxia group(hypoxia culture) and BDNF group(hypoxia culture into which BDNF was added).After cultured for 36 h,the culture condition was changed to induce differentiation of the cells at 24,48 and 72 h.Expression levels of Bcl-2,bax,nse,nne and gfap mRNA in each group were measured by RT-PCR and Western blot,respectively,at 48 h after culture.Results The bcl-2 expression level was significantly higher in BDNF group than in hypoxia group at 48 h whereas the bax expression level was significantly lower at 48 and 72 h in apoptotic genes(P<0.05).The nse and nne expression levels were significantly higher whereas the gfap expression level was significantly lower at 24 h in differentiated genes(P<0.05).The nse expression level was significantly higher whereas the gfap expression level was significantly lower at 48 h in differentiated genes(P<0.05).Conclusion Hypoxia can lead to differentiation of neural stem cells to neural glial cells and BDNF can induce differentiation of neural stem cells to neurons.