重复性短暂缺血诱导的心脏血管生成由钙/钙调蛋白依赖性蛋白激酶II激活介导。

Repetitive Transient Ischemia-Induced Cardiac Angiogenesis is Mediated by Camkii Activation.

作者信息

Chen Zhuobin, Li Benlei, Dong Qiaoqiao, Qian Cheng, Cheng Jun, Wang Yanggan

机构信息

Department of Cardiology, Zhongnan Hospital of Wuhan University, Wuhan, China.

Medical Research Institute of Wuhan University, Wuhan University, Wuhan, China.

出版信息

Cell Physiol Biochem. 2018;47(3):914-924. doi: 10.1159/000490133. Epub 2018 May 24.

DOI:10.1159/000490133

PMID:29843150

Abstract

BACKGROUND/AIMS: Coronary angiogenesis is an important protective mechanism in response to myocardial ischemia in coronary artery disease. However, the underlying mechanisms remain largely unclear. Here, we investigated the role of CaMKII activation in ischemia-induced cardiac angiogenesis.

METHODS

Repetitive transient ischemia model was established in C57/BL6 mice by daily multiple episodes (3 times/day) of short time (5 min) occlusion of the left anterior descending coronary artery for 7 days. Coronary angiogenesis was detected by immunofluorescent staining. RT-qPCR and Western blot analyses were used to detect the mRNA and protein levels of CaMKII, p-CaMKII and VEGF. Primary cardiac microvascular endothelial cells (CMECs) were isolated to investigate the effects of KN93 on cell proliferation and migration in hypoxic condition.

RESULTS

We found that angiogenesis was induced in the ischemic myocardium and suppressed by chronic intraperitoneal injection of CaMKII inhibitor KN93. RT-qPCR and Western blot analyses showed that myocardial ischemia induced an increased expression and autophosphorylation of CaMKII. VEGF expression was increased in the ischemia model but blunted by KN93. Moreover, KN93 suppressed the proliferation and migration of cardiac endothelial cells in hypoxic condition in which the protein expression of CaMKII, p-CaMKII and VEGF was increased.

CONCLUSION

CaMKII is an important mediator for the ischemia-induced coronary angiogenesis, in which CaMKII-triggered VEGF expression plays a key role.

摘要

背景/目的：冠状动脉血管生成是冠心病中对心肌缺血的一种重要保护机制。然而，其潜在机制仍 largely 不清楚。在此，我们研究了 CaMKII 激活在缺血诱导的心脏血管生成中的作用。

方法

通过每日多次（3 次/天）短暂（5 分钟）阻断左前降支冠状动脉 7 天，在 C57/BL6 小鼠中建立重复性短暂缺血模型。通过免疫荧光染色检测冠状动脉血管生成。采用 RT-qPCR 和 Western blot 分析检测 CaMKII、p-CaMKII 和 VEGF 的 mRNA 和蛋白水平。分离原代心脏微血管内皮细胞（CMECs），研究 KN93 在缺氧条件下对细胞增殖和迁移的影响。

结果

我们发现缺血心肌中诱导了血管生成，并被慢性腹腔注射 CaMKII 抑制剂 KN93 所抑制。RT-qPCR 和 Western blot 分析表明，心肌缺血诱导 CaMKII 的表达和自磷酸化增加。在缺血模型中 VEGF 表达增加，但被 KN93 减弱。此外，KN93 在缺氧条件下抑制了心脏内皮细胞的增殖和迁移，在该条件下 CaMKII、p-CaMKII 和 VEGF 的蛋白表达增加。