Role of protein kinase Cζ in thrombin-induced endothelial permeability changes:: inhibition by angiopoietin-1
Role of protein kinase Cζ in thrombin-induced endothelial permeability changes:: inhibition by angiopoietin-1
复制标题
DOI：
10.1182/blood-2003-11-3744
复制
发表时间：
2004-09-15
期刊：
影响因子：
20.3
通讯作者：
Gamble, JR
中科院分区：
文献类型：
--
作者：
Li, XC;Hahn, CN;Gamble, JR
内皮细胞渗漏是由促进内皮通透性的凝血酶和抗炎剂如血管生成素-1调节的。在这里，我们定义了一个涉及凝血酶诱导通透性的新途径，涉及非典型蛋白激酶C异构体PKCzeta。化学抑制剂研究暗示了一种非典型PKCzeta亚型参与了人脐静脉内皮细胞凝血酶诱导的通透性改变。凝血酶刺激导致PKCzeta易位到膜上，而另一种非典型PKCzeta异构体PKClambda不易位，这是酶激活的关键事件。PKCzeta的参与通过组成活性PKCzeta的过表达得到证实，导致基础通透性增强。显性阴性PKCzeta抑制凝血酶介导的内皮细胞通透性，抑制凝血酶诱导的PKCzeta活化。无论在PKCzeta的上游还是下游，Rho活化似乎都不起作用，因为C3转移酶不能阻断凝血酶诱导的PKCzeta活化，而显性阴性PKCzeta也不能阻断凝血酶诱导的Rho活化。最后，我们发现血管生成素-1抑制凝血酶诱导的PKCzeta激活、Rho激活和Ca++通量，从而证明血管生成素-1强大的抗渗透性作用是通过其对凝血酶诱导的一系列信号通路的作用介导的，并与渗透性变化有关。(C) 2004年由美国血液病学会出版。
Endothelial cell leakiness is regulated by mediators such as thrombin, which promotes endothelial permeability, and anti-inflammatory agents, such as angiopoietin-1. Here we define a new pathway involved in thrombin-induced permeability that involves the atypical protein kinase C isoform, PKCzeta. Chemical inhibitor studies implicated the involvement of an atypical PKCzeta isoform in thrombin-induced permeability changes in human umbilical vein endothelial cells. Thrombin stimulation resulted in PKCzeta, but not the other atypical PKCzeta isoform, PKClambda, translocating to the membrane, an event known to be critical to enzyme activation. The involvement of PKCzeta was confirmed by overexpression of constitutively active PKCzeta, resulting in enhanced basal permeability. Dominant-negative PKCzeta prevented the thrombin-mediated effects on endothelial cell permeability and inhibited thrombin-induced activation of PKCzeta. Rho activation does not appear to play a role, either upstream or downstream of PKCzeta, as C3 transferase does not block thrombin-induced PKCzeta activation and dominant-negative PKCzeta does not block thrombin-induced Rho activation. Finally, we show that angiopoietin-1 inhibits thrombin-induced PKCzeta activation, Rho activation, and Ca++ flux, thus demonstrating that the powerful antipermeability action of angiopoietin-1 is mediated by its action on a number of signaling pathways induced by thrombin and implicated in permeability changes. (C) 2004 by The American Society of Hematology.