Park Kwang-Hyun, Lee Young-Rae, Hur Hyeon, Yu Hong-Nu, Rah So-Young, Kim Uh-Hyun, Yu Kang-Yeol, Jin Chan-Moon, Han Myung-Kwan, Kim Jong-Suk
Department of Biochemistry, Institute for Medical Sciences, Chonbuk National University Medical School, Jeonju, Republic of Korea.
Microb Pathog. 2009 Jul;47(1):47-51. doi: 10.1016/j.micpath.2009.04.014. Epub 2009 May 15.
Endothelial hyperpermeability, a hallmark of septicemia, is induced by stress fiber formation, which is primarily regulated by the calcium/calmodulin signaling pathway in endothelial cells. We previously reported that trifluoperazine, a calcium/calmodulin antagonist, blocks Vibrio vulnificus cytolysin (VVC) -induced lethality at in vivo animal model. The object of this study was therefore to examine whether VVC induces stress fiber formation through calcium/calmodulin signaling in endothelial cells. Here, we monitored calcium-influx after treatment of VVC using confocal microscopy in CPAE cells, pulmonary endothelial cell line. Interestingly, we found that VVC-induced dose-dependently increases of Ca(2+) in CPAE cells. Moreover, VVC-induced stress fiber formation as well as phosphorylation of myosin light chain (MLC) in a dose- and time-dependent manner, which was completely blocked by trifluoperazine. These results suggest that the calcium/calmodulin signaling pathway plays a pivotal role in VVC-induced hyperpermeability.
内皮细胞高通透性是败血症的一个标志，它由应力纤维形成所诱导，而应力纤维形成主要由内皮细胞中的钙/钙调蛋白信号通路调控。我们之前报道过，三氟拉嗪，一种钙/钙调蛋白拮抗剂，在体内动物模型中可阻断创伤弧菌溶血素（VVC）诱导的致死性。因此，本研究的目的是检测VVC是否通过内皮细胞中的钙/钙调蛋白信号传导诱导应力纤维形成。在此，我们使用共聚焦显微镜在肺内皮细胞系CPAE细胞中监测了VVC处理后的钙内流。有趣的是，我们发现VVC在CPAE细胞中剂量依赖性地诱导Ca(2+)增加。此外，VVC以剂量和时间依赖性方式诱导应力纤维形成以及肌球蛋白轻链（MLC）磷酸化，而这被三氟拉嗪完全阻断。这些结果表明钙/钙调蛋白信号通路在VVC诱导的高通透性中起关键作用。
