Department of Molecular Pathobiology and Cell Adhesion Biology, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu-city, Mie 514-8507, Japan.
Faculty of Medical Engineering, Suzuka University of Medical Science, 1001-1 Kishioka-cho, Suzuka-city, Mie 510-0293, Japan.
Exp Cell Res. 2014 Feb 15;321(2):133-41. doi: 10.1016/j.yexcr.2013.12.002. Epub 2013 Dec 11.
The gap junction proteins connexin32 (Cx32), Cx37, Cx40, and Cx43 are expressed in endothelial cells, and regulate vascular functions involving inflammation, vasculogenesis and vascular remodeling. Aberrant Cxs expression promotes the development of atherosclerosis which is modulated by angiogenesis; however the role played by endothelial Cxs in angiogenesis remains unclear. In this study, we determined the effects of endothelial Cxs, particularly Cx32, on angiogenesis. EA.hy926 cells that had been transfected to overexpress Cx32 significantly increased capillary length and the number on branches compared to Cx-transfectant cells over-expressing Cx37, Cx40, and Cx43 or mock-treated cells. Treatment via intracellular transfer of anti-Cx32 antibody suppressed tube formation of human umbilical vein endothelial cells (HUVECs) compared to controls. In vitro wound healing assays revealed that Cx32-transfectant cells significantly increased the repaired area while anti-Cx32 antibody-treated HUVECs reduced it. Ex vivo aorta ring assays and in vivo matrigel plaque assays showed that Cx32-deficient mice impaired both vascular sprouting from the aorta and cell migration into the implanted matrigel. Therefore endothelial Cx32 facilitates tube formation, wound healing, vascular sprouting, and cell migration. Our results suggest that endothelial Cx32 positively regulates angiogenesis by enhancing endothelial cell tube formation and cell migration.
缝隙连接蛋白 connexin32 (Cx32)、Cx37、Cx40 和 Cx43 在内皮细胞中表达，并调节涉及炎症、血管生成和血管重塑的血管功能。异常的 Cxs 表达促进了动脉粥样硬化的发展，而血管生成对其有调节作用；然而，内皮细胞 Cxs 在血管生成中的作用尚不清楚。在这项研究中，我们确定了内皮细胞 Cxs，特别是 Cx32，对血管生成的影响。与过表达 Cx37、Cx40 和 Cx43 的 Cx 转染细胞或对照细胞相比，过表达 Cx32 的 EA.hy926 细胞显著增加了毛细血管长度和分支数量。与对照相比，通过细胞内转染抗 Cx32 抗体处理抑制了人脐静脉内皮细胞 (HUVEC) 的管形成。体外划痕愈合实验表明，Cx32 转染细胞显著增加了修复面积，而抗 Cx32 抗体处理的 HUVEC 则减少了修复面积。在体主动脉环实验和体内基质胶斑块实验表明，Cx32 缺陷小鼠损害了主动脉的血管发芽和细胞向植入的基质胶中的迁移。因此，内皮细胞 Cx32 通过促进内皮细胞管形成和细胞迁移来促进管形成、伤口愈合、血管发芽和细胞迁移。我们的结果表明，内皮细胞 Cx32 通过增强内皮细胞管形成和细胞迁移来正向调节血管生成。
