脑微血管内皮细胞通过分泌血管内皮生长因子促进神经干细胞增殖的研究

The proliferation of neural stem cells promoted by vascular endothelial growth factor secreted by cerebral microvascular endothelial cells

目的:观察脑微血管内皮细胞通过分泌血管内皮生长因子(vascular endothelial growth factor,VEGF)对神经干细胞增殖的影响并探讨可能的机制。方法:取新生SD大鼠,进行脑微血管内皮细胞与神经干细胞的原代培养、分离及传代,然后通过形态学和免疫荧光法鉴定。使用transwell小室建立脑微血管内皮细胞与神经干细胞非接触性的共培养系统。实验分为共培养组、单纯神经干细胞培养组和VEGF拮抗剂组。通过MTS方法检测不同组神经干细胞的增殖;通过酶联免疫法检测各组细胞上清液中VEGF的表达。结果:与单纯神经干细胞培养组及VEGF拮抗剂组相比,共培养组的神经干细胞显示出增殖增加,且共培养组的细胞上清液中VEGF表达升高。结论:脑微血管内皮细胞和神经干细胞共培养可促进神经干细胞的增殖,其中脑微血管内皮细胞分泌的VEGF可能起关键的调控作用。

Objective To investigate the effects of vascular endothelial growth factor （VEGF） secreted by cerebral microvaseular endothelial cells （CMEC） on the proliferation of neural stem cells （NSC） and the potential mechanism. Methods Primary CMEC and NSC were isolated from neonatal SD rats. Both cells were identified through morphology and immunofluorescence. CMEC and NSC were co-cuhured by transwell. Three groups were assigned： CMEC and NSC co-culture group, NSC culture group and VEGF antagonist group. The proliferation of NSC was assessed by MTS ; and the expression of VEGF in culture supematant was measured by ELISA. Results As compared with those in NSC culture group and VEGF antagonist group, the proliferation of NSC and the expression of VEGF in culture supernatant in CMEC and NSC co-culture group were significantly increased （P 〈 0.05）. Conclusion CMEC could significantly promote the proliferation of NSC by secreting VEGF.