【摘要】 目的探讨脑梗死后脑内肿瘤坏死因子(tumor necrosis factor,TNF-α)升高、整合素α5β1和αVβ3上调及血管新生间的关系。方法选取患者因大面积梗死切除的缺血脑组织,依梗死不同时间,分成1 d、2 d和4 d3个组,以脑肿瘤患者手术入路中必须切除的正常脑组织为对照,以CD31和Ki67的双重免疫荧光染色检测脑内皮细胞增殖;ELISA检测脑组织中TNF-α、纤维素连接蛋白(Fn)受体整合素α5β1和αVβ3的表达;双重免疫荧光染色检测血管上Fn、α5β1和αVβ3表达;流式细胞仪测培养的人内皮细胞上整合素α5、β1、αV和β3表达。结果脑梗死后第1天缺血区TNF-α即明显升高,2 d达高峰,4 d时趋于下降,均显著高于对照组(P<0.01);缺血区脑组织中和血管上Fn及α5β1和αVβ3表达上调,4 d时较对照组显著增加(P<0.05),且与脑内皮细胞增殖时相一致;体外研究证实TNF-α可促进人内皮细胞上5β1和αVβ3上调。结论脑梗死后早期升高的TNF-α通过上调血管上α5β1和αVβ3表达进而促进脑内血管新生。更多还原

【Abstract】 Objective To investigate the relationships between the upregulation of Tumor necrosis factor α( TNF-α),expression patterns of α5β1 and αVβ3 integrins on blood vessels and angiogenesis after cerebral ischemic stroke. Methods Brain ischemic tissue specimens were obtained from 13 patients with ischemic stroke,according to the time point after cerebral ischemic stroke,three groups were studied: 1 d,2 d and 4 d groups. And 5 normal brain tissue specimens were chosen for control subjects.ELISA was used to detect the expression of TNF-α),fibronectin( Fn),α5β1 and αVβ3 integrins in the cerebral ischemic brain.The brain endothelial cells( BECs) proliferation was assessed by performing dual-immunofluorescent staning( IF) for Ki67 and CD31 and the expression patterns of Fn,α5β1 and αVβ3 on blood vessels was assessed by performing dual-IF for CD31 / α5,CD31 / β3 and CD31 / Fn. Results The TNF-α in the ischemic brain increased at day 1,peaked at day 2,then declined at day 4.The contents of TNF-α at different time point were all significantly higher than that of the control brains( P < 0. 01). The expression of α5β1 and αVβ3 integrins in the ischemic brain as well as the Fn,α5β1 and-αVβ3 on blood vessels was parallelly upregulated with time,and the expression of all the three markers at day 4 was significantly higher than that of the controls,which exactly coincided with the time course of BECs proliferation. Conclusions The early upregulation of TNF-α) after cerebral ischemia stroke promotes the angiogenesis by inducing the expression of α5β1 and αVβ3 on blood vessels.更多还原