低氧促进神经干细胞增殖分化过程中低氧诱导因子-1α表达的变化

Alteration of hypoxia inducible factor-1α expression during proliferation and differentiation of neural stem cells induced by hypoxia

目的:观察小鼠胎脑皮质神经干细胞(NSCs)在体外低氧条件下细胞增殖与分化以及低氧诱导因子-1α(HIF-1α)的表达情况,分析HIF-1α对NSCs增殖与分化的作用。方法:体外低氧条件下(3%O2)培养扩增胚鼠皮质来源的细胞,实验分低氧1、2、3、4d组,常氧组为对照。免疫细胞化学染色法鉴定神经干细胞及其子代细胞,RT-PCR检测实验组细胞HIF-1α mRNA的表达。结果:低氧4d组细胞呈HIF-1α阳性,其余HIF-1α为阴性。实验组神经元特异性烯醇酶(NSE)平均灰度值进行性增加。各实验组HIF-1α mRNA与对照组相比具有显著性差异。结论:在低氧能促进NSCs的增殖与分化过程中,HIF-1α表达变化可能在其中发挥了重要作用。

Objective： To observe the proliferation and differentiation of cortical neural stem cells （NSCs） from embryonic mice and the expression of hypoxia inducible factor-1α （HIF-1α）, and to analyze the contribution of HIF-1α on NSCs. Methods： NSCs from brain cortex of embryonic mice were cultured and amplificated in lower O2 （ 3 % O2 ） in vitro, and all experimental dishes were divided into hypoxia for 1, 2, 3 and 4 days group; The normoxic group was as control. Immunocytochemical techniques were used to identify stem cells and their progenies, HIF-1α mRNA expression in NSCs was examined by RT PCR. Results： HIF-1α positive cells could be detected in group hypoxia for 4 days, while in the other groups, no positive cells were detected. The mean gray value of neuron-specific enolase （NSE） of experimental groups enhanced gradually. Significant difference of the relative expression levels of HIF-1α mRNA in experimental groups could be found, compared with the control group. Conclusion： During proliferation and differentiation of cortical NSCs induced by hypoxia, the alteration in HIF-1α expression may participate in the process.