Cytoskeletal regulation of endothelial barrier function by WAVE2

WAVE2 对内皮屏障功能的细胞骨架调节

• 批准号: 7844951
• 负责人: SUNIL K SHAW
• 金额: $ 22.26万
• 依托单位: WOMEN AND INFANTS HOSPITAL-RHODE ISLAND
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-01 至 2012-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7844951
• 关键词: Actins; Adherence; Asthma; Atherosclerosis; Autoimmune Diseases; Blood; Blood Vessels; Cells; Chronic; Clinical; Complex; Cyclic AMP; Cyclic AMP-Dependent Protein Kinases; Cytoskeleton; Data; Diabetes Mellitus; Disease; Endothelial Cells; Endothelium; Extravasation; Family; In Vitro; Indium; Individual; Inflammation; Inflammatory; Injury; Intercellular Junctions; Intervention; Lead; Leukocytes; Measures; Mediator of activation protein; Microfilaments; Molecular; Monomeric GTP-Binding Proteins; Nutrient; Pathway interactions; Permeability; Play; Process; Protein Kinase; Proteins; Regulation; Role; Second Messenger Systems; Septic Shock; Signal Pathway; Signal Transduction; Stimulus; Testing; Therapeutic; Tight Junctions; Tissues; Waste Products; base; combat; design; improved; in vivo; interest; macromolecule; member; monolayer; neuronal cell body; pathogen; polymerization; public health relevance; receptor; receptor coupling; response; second messenger

DESCRIPTION (provided by applicant): Endothelial cells which line blood vessels are a critical element in barrier function. They regulate the passage between blood and tissues of macromolecules, nutrients and waste products. During inflammation, endothelial barrier function is reduced, leading to accumulation of leukocytes and leakage of inflammatory molecules into target tissue. While inflammation is a necessary response to pathogens and tissue damage, when it becomes chronic or dysregulated it is associated with tissue injury and serious diseases such as atherosclerosis, asthma, diabetes, septic shock and autoimmune diseases. Control of inflammation is therefore central to many clinical interventions, and reversing the loss of endothelial barrier function during inflammation has significant therapeutic value. Several mediators have been identified that augment endothelial barrier function. For example, signals to receptors which couple to Gs trigger an increase in the second messenger cAMP. This typically results in improved barrier function in vitro and in vivo, largely through regulation of endothelial junctions. In endothelium, the major effector for cAMP was thought to be cAMP dependent protein kinase (PKA). Recently, activation of the small GTPase Rap1 has been shown to dramatically improve the endothelial barrier, causing polymerization of actin at the junctions. Junctional actin is an essential component of adherence and tight junctions. This proposal will focus on proteins that promote actin filament nucleation at endothelial junctions. Preliminary studies indicate that WAVE2, a member of the WASP-WAVE family of actin nucleation promoting factors, may cooperate with the Arp2/3 complex at endothelial junctions to cause actin polymerization. Based on these observations it is hypothesized that WAVE2 lies downstream of cAMP signaling, and plays a critical role in regulating endothelial barrier function by nucleating actin polymerization at the junctions. This hypothesis will be tested in the following specific aims: 1. Identify and localize components of the WAVE2 signaling pathway in endothelial cells; 2. Measure the functional effect of WAVE2 on monolayer permeability and the structural effect on junctional composition using a variety of strategies to interfere with its signaling. These studies will test the role for WAVE2 in polymerization of junctional actin and barrier function in endothelial cells in response to barrier strengthening and weakening stimuli. Identification of the molecular mechanisms that regulate endothelial barrier function will lead to better understanding of the inflammatory process, and is a necessary step towards design of more specific therapies to combat it dysregulation. PUBLIC HEALTH RELEVANCE: Inflammation is a necessary response to pathogens and tissue damage, but when it becomes chronic or dysregulated it is associated with tissue injury and serious diseases such as atherosclerosis, asthma, diabetes, septic shock and autoimmune diseases. During inflammation, endothelial barrier function is reduced, leading to accumulation of leukocytes and leakage of inflammatory molecules into target tissue. This proposal will identify one of the molecular mechanisms that regulate endothelial barrier function which will lead to better understanding of the inflammatory process, and is a necessary step towards design of more specific therapies to combat its dysregulation.

描述（由申请人提供）：线血管的内皮细胞是屏障功能的关键要素。它们调节大分子，营养和废物产物的血液与组织之间的传递。在炎症过程中，内皮屏障功能降低，导致白细胞积累并炎症分子渗入靶组织。虽然炎症是对病原体和组织损伤的必要反应，但当炎症变得慢性或失调时，它与组织损伤和严重疾病有关，例如动脉粥样硬化，哮喘，糖尿病，败血症性休克和自身免疫性疾病。因此，炎症的控制对于许多临床干预措施至关重要，并且在炎症过程中逆转内皮屏障功能的丧失具有显着的治疗价值。已经确定了几个介体可以增强内皮屏障功能。例如，向夫妇与GS的受体发出信号引发了第二邮箱训练营的增加。这通常会在体外和体内提高屏障功能，主要通过调节内皮连接。在内皮中，cAMP的主​​要效应子被认为是cAMP依赖性蛋白激酶（PKA）。最近，已经显示出小的GTPase RAP1的激活可显着改善内皮屏障，从而在连接处引起肌动蛋白的聚合。连接肌动蛋白是依从性和紧密连接的重要组成部分。该建议将集中于促进内皮连接处肌动蛋白丝核的蛋白质。初步研究表明，Wave2是肌动蛋白成核促进因子家族的成员，可以与内皮连接处的ARP2/3复合物合作，以引起肌动蛋白聚合。基于这些观察结果，假设Wave2位于cAMP信号的下游，并且通过在连接处通过核定肌动蛋白聚合来调节内皮屏障功能起着至关重要的作用。该假设将在以下特定目的中进行检验：1。识别和定位内皮细胞中Wave2信号通路的成分； 2。使用多种策略来介绍各种策略来干扰其信号传导，测量波2对单层通透性的功能效应和对连接组成的结构效应。这些研究将测试波2在响应屏障增强和减弱刺激的情况下，在内皮细胞中连接肌动蛋白和屏障功能的聚合中的作用。鉴定调节内皮屏障功能的分子机制将使人们更好地了解炎症过程，这是设计更具体的疗法以应对其失调的必要步骤。公共卫生相关性：炎症是对病原体和组织损害的必要反应，但是当炎症变得慢性或失调时，它与组织损伤和严重疾病有关，例如动脉粥样硬化，哮喘，糖尿病，败血性休克和自身免疫性疾病。在炎症过程中，内皮屏障功能降低，导致白细胞积累并炎症分子渗入靶组织。该建议将确定调节内皮屏障功能的分子机制之一，这将使人们更好地了解炎症过程，这是设计更具体的疗法以应对其失调的必要步骤。