Focal adhesion kinase regulation of lung vascular permeability and edemagenesis

描述(申请人提供)：肺血管屏障功能丧失和炎症细胞浸润是急性肺损伤(ALI)的两个主要特征。该项目将探讨内皮细胞粘着斑激酶(FAK)通过抑制细胞内钙升高来调节肺血管通透性增加和炎症反应的基本概念。我们将检验FAK诱导针对钙离子感受器基质相互作用分子1(STIM1)的microRNA-150(miR-150)表达的假设。我们推测，通过这种机制下调STIM1对于阻断内皮细胞中的钙信号，从而防止肺血管屏障的破坏和炎症是至关重要的。为了解决这一假设，我们建立了一种新的三苯氧胺诱导的内皮细胞(EC)特异性FAK基因敲除(EC-FAK-/-)以及EC-STIM1-/-小鼠模型。我们将解决以下目标：目的#1，确定FAK在调节肺液平衡和利用内皮细胞特异性FAK缺失小鼠调节肺部炎症中的作用；目的#2，确定FAK在抑制STIM1活性从而阻断钙离子进入信号中的作用，从而介导肺血管通透性和炎症增加；以及目的#3，确定miR-150作为FAK的关键效应因子的作用，该效应针对STIM1，从而防止肺血管通透性和炎症增加。这些研究将结合成像、遗传学和生理学方法，对内皮细胞FAK在调节肺液稳态和炎症中的作用进行全面和综合的研究。这些研究的结果将有可能确定针对ALI的新的治疗靶点。

DESCRIPTION (provided by applicant): Loss of lung vascular barrier function and inflammatory cell infiltration are two cardinal features of acute lung injury (ALI). The project wil investigate the fundamental concept that endothelial focal adhesion kinase (FAK) modulates the increase in lung vascular permeability and the inflammatory response by suppressing intracellular Ca2+ rise. We will test the hypothesis that FAK induces microRNA-150 (miR-150) expression which targets the Ca2+ sensor, stromal interacting molecule 1 (STIM1). We postulate that STIM1 downregulation by this mechanism is crucial for blocking Ca2+ signaling in endothelial cells and thereby prevents disruption of lung vascular barrier and inflammation. To address this hypothesis, we have generated a novel tamoxifen-inducible endothelial cell (EC)-specific FAK knockout (EC-FAK-/-) as well as EC-STIM1-/- mouse models. We will address the following aims: Aim #1, To define the role of FAK in regulating lung fluid balance and modulating lung inflammation using endothelial cell-specific FAK null mice; Aim #2, To determine the role of FAK in suppressing STIM1 activity and thereby blocking Ca2+ entry signals mediating increased lung vascular permeability and inflammation; and Aim #3, To define the role of miR-150 as an essential effector of FAK that targets STIM1 and thus prevents increased lung vascular permeability and inflammation. These studies will use a combination of imaging, genetic, and physiological approaches to develop a comprehensive and integrated picture of the role of endothelial FAK in regulating lung fluid homeostasis and inflammation. The results of these studies will have the potential of defining novel therapeutic targets directed against ALI.