Bai Yingnan, Liu Rongle, Li Zhixing, Zhang Yaqi, Wang Xiaoyan, Wu Jian, Li Zhuoquan, Qian Sanli, Li Bingyu, Zhang Zhenzhong, Fathy Abdel Hamid, Cappetta Donato, Zhou Jingmin, Zou Yunzeng, Qian Juying, Ge Junbo
Department of Cardiology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai 200032, China.
Institute of Biomedical Science, Fudan University, Shanghai 200032, China.
J Thorac Dis. 2019 May;11(5):1849-1859. doi: 10.21037/jtd.2019.05.18.
The regulation of angiogenesis in the treatment of cardiovascular diseases has been widely studied and the vascular endothelial growth factor (VEGF) families and VEGF receptor (VEGFR) have been proven to be one of the key regulators. The VEGFR endocytosis has been recently proved to be involved in the regulation of angiogenesis. Our previous study showed that the upregulation of VEGFR endocytosis enhanced angiogenesis . In this research, we utilized mice with induced hindlimb ischemia, as a model to investigate the role of VEGFR endocytosis in the regulation of angiogenesis . Our goal was to observe the effect of revascularization with different degrees of VEGFR endocytosis after injecting atypical protein kinase C inhibitor (αPKCi) and dynasore, which could respectively promote and inhibit the VEGFR endocytosis.
We induced the hindlimb ischemia in adult male mice by ligating the hindlimb artery. By directly injecting the ischemic muscles with endothelial progenitor cells (EPCs) alone or EPCs + αPKCi/EPCs + dynasore or control medium (sham group), we divided the mice into four groups and detected lower limb blood flow using a laser Doppler blood perfusion imager. We also measured the immunohistochemistry (IHC) of markers for angiogenesis, such as CD31 and alpha smooth muscle actin (α-SMA) in the ischemic hindlimb tissues.
We demonstrated VEGFR endocytosis played an important role in the angiogenesis of the ischemic hindlimb model . By using atypical PKC inhibitor that increase the VEGFR endocytosis, the angiogenesis in the mice model was promoted. Treatment with EPCs + αPKCi showed greater effects on blood perfusion recovery and increased the α-SMA-positive vessels.
The regulation of VEGFR endocytosis represents a valuable method of improving angiogenesis and thus revascularization in ischemic disease model.
血管生成在心血管疾病治疗中的调控已得到广泛研究，血管内皮生长因子（VEGF）家族和VEGF受体（VEGFR）已被证明是关键调控因子之一。最近已证实VEGFR内吞作用参与血管生成的调控。我们之前的研究表明，VEGFR内吞作用的上调可增强血管生成。在本研究中，我们利用诱导后肢缺血的小鼠作为模型，来研究VEGFR内吞作用在血管生成调控中的作用。我们的目标是观察在注射非典型蛋白激酶C抑制剂（αPKCi）和dynasore后，不同程度的VEGFR内吞作用对血管再通的影响，αPKCi和dynasore可分别促进和抑制VEGFR内吞作用。
我们通过结扎后肢动脉诱导成年雄性小鼠后肢缺血。通过单独向缺血肌肉直接注射内皮祖细胞（EPCs）或EPCs + αPKCi/EPCs + dynasore或对照培养基（假手术组），将小鼠分为四组，并使用激光多普勒血流灌注成像仪检测下肢血流。我们还测量了缺血后肢组织中血管生成标志物的免疫组织化学（IHC），如CD31和α平滑肌肌动蛋白（α-SMA）。
我们证明VEGFR内吞作用在缺血后肢模型的血管生成中起重要作用。通过使用增加VEGFR内吞作用的非典型PKC抑制剂，可促进小鼠模型中的血管生成。EPCs + αPKCi治疗对血流灌注恢复有更大影响，并增加了α-SMA阳性血管。
VEGFR内吞作用的调控是改善缺血疾病模型中血管生成从而实现血管再通的一种有价值的方法。
