Zheng Zhenzhong, Liu Zhengxiang
Department of Cardiology of Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China.
Mol Med. 2006 Sep-Oct;12(9-10):214-20. doi: 10.2119/2006-00037.Zheng.
Our previous study showed that CD151 promotes neovascularization and improves blood perfusion in a rat hindlimb ischemia model. In this study, we investigated whether CD151 promotes neovascularization and improves ventricular function after myocardial infarction in rats and the mechanisms involved. Rats were subjected to sham surgery or coronary artery ligation. We used rAAV for direct delivery of the human CD151 gene into the rat myocardium. At 4 weeks after coronary artery ligation, human CD151 mRNA was detected using RT-PCR. Measurement of capillary density was evaluated using immunostaining for von Willebrand factor, and hemodynamic variables and physiological parameters were monitored. Western blot analysis for CD151, PI3K, phosphor-Akt, total Akt, phosphor-eNOS, and total eNOS was performed. In addition, we also observed the effect of CD151 on the expression of VEGF using Western blot analysis. CD151 gene delivery could increase the expression of CD151 at gene and protein levels. Overexpression of CD151 could increase the number of microvessels in the ischemic myocardium and significantly improved the hemodynamic variables after myocardial infarction. In addition, CD151 could activate the PI3K pathway, including activation of Akt and eNOS, but did not affect the expression of VEGF. This study suggested that CD151 could promote neovascularization and improve ventricular function after myocardial infarction in rats. The mechanism may be that CD151 can activate the PI3K pathway and promote neovascularization via the PI3K pathway, without affecting ischemia-induced VEGF expression.
我们之前的研究表明,在大鼠后肢缺血模型中,CD151可促进新血管形成并改善血液灌注。在本研究中,我们调查了CD151是否能促进大鼠心肌梗死后的新血管形成并改善心室功能及其相关机制。对大鼠进行假手术或冠状动脉结扎。我们使用重组腺相关病毒(rAAV)将人CD151基因直接导入大鼠心肌。冠状动脉结扎4周后,采用逆转录聚合酶链反应(RT-PCR)检测人CD151 mRNA。使用血管性血友病因子免疫染色评估毛细血管密度,并监测血流动力学变量和生理参数。对CD151、磷脂酰肌醇-3-激酶(PI3K)、磷酸化蛋白激酶B(phosphor-Akt)、总蛋白激酶B(total Akt)、磷酸化内皮型一氧化氮合酶(phosphor-eNOS)和总内皮型一氧化氮合酶(total eNOS)进行蛋白质印迹分析。此外,我们还通过蛋白质印迹分析观察了CD151对血管内皮生长因子(VEGF)表达的影响。CD151基因递送可在基因和蛋白水平增加CD151的表达。CD151过表达可增加缺血心肌中的微血管数量,并显著改善心肌梗死后的血流动力学变量。此外,CD151可激活PI3K通路,包括激活Akt和eNOS,但不影响VEGF的表达。本研究表明,CD151可促进大鼠心肌梗死后的新血管形成并改善心室功能。其机制可能是CD151可激活PI3K通路,并通过PI3K通路促进新血管形成,而不影响缺血诱导的VEGF表达。