Rho Regulation of Pulmonary Vascular Permeability

Rho 对肺血管通透性的调节

• 批准号: 7584300
• 负责人: DOLLY MEHTA
• 金额: $ 39.25万
• 依托单位: UNIVERSITY OF ILLINOIS AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-01 至 2013-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7584300
• 关键词: 1,2-diacylglycerol; Accounting; Acute; Acute Lung Injury; Address; Agonist; Ankyrins; Binding; Blood; Blood Vessels; Calcium Channel; Cations; Cell surface; Coupled; Data; Development; Diglycerides; Edema; Endothelial Cells; Extravasation; GTP-Binding Proteins; Generations; Genes; Genetic Polymorphism; Guanosine Triphosphate Phosphohydrolases; Heterotrimeric GTP-Binding Proteins; Homologous Gene; Inflammatory; Lead; Link; Lipids; Liquid substance; Lung; MYLK gene; Mediating; Microvascular Permeability; Mus; Myosin Light Chain Kinase; Nucleotides; Pathogenesis; Pathway interactions; Patients; Permeability; Phosphoric Monoester Hydrolases; Phosphotransferases; Plasma Proteins; Protein Isoforms; Protein phosphatase; Proteinase-Activated Receptors; Proteins; Proto-Oncogene Protein pp60 (c-src); Regulation; Role; Signal Pathway; Signal Transduction; Stream; Structure of parenchyma of lung; Testing; Therapeutic; Thrombin; Thrombin Receptor; Tissues; Vascular Permeabilities; base; effective therapy; insight; lung injury; macromolecule; monolayer; novel; prevent; public health relevance; pulmonary vascular permeability; receptor; receptor operated channel; response; rho; src-Family Kinases; tensin; therapeutic development

DESCRIPTION (provided by applicant): Increased lung vascular endothelial permeability leads to the leakage of fluid and plasma proteins into lung tissue, a primary factor in the pathogenesis of Acute Lung Injury (ALI). Our studies will investigate the fundamental question that Ca2+ entry mediated by transient receptor potential cation channel 6 (TRPC6), a receptor-operated channel (ROC), is a critical determinant of increased endothelial permeability. We will test the hypothesis that TRPC6 activation is required and sufficient for endothelial contraction that mediates increased lung vascular permeability. The proposed studies will use the agonist thrombin, which activates protease activating receptor (PAR-1) on the endothelial cell surface and produces diacylglycerol, the direct activator of the TRPC6 channel. Studies will determine the role of dual lipid/protein phosphatase PTEN in the mechanism of TRPC6 activation. We will address the role of TRPC6-mediated increase in intracellular Ca2+ as a requirement for signaling the activation of RhoA and MLCK-L, and thereby promoting endothelial cell contraction. Our Specific Aims are to determine 1) role of endothelial ROC, TRPC6 in mediating Ca2+ signaling dependent increases in lung microvascular permeability, 2) PTEN-mediated mechanism of activation of TRPC6 and its consequences in the regulation of endothelial barrier function, and 3) downstream signaling mechanisms of TRPC6-induced increase in lung endothelial permeability involving the activation of PKCa and p60Src kinase and the effectors RhoA and MLCK-L isoform. These studies will be carried out at multiple levels including utilizing endothelial cells and lungs from mice carrying deletions in specific genes. Our hope is that the proposal will provide novel insights into the development of therapeutic strategies directed against TRPC6 that will prevent lung vascular "leakiness". PUBLIC HEALTH RELEVANCE: The semi-selective endothelial cell monolayer partitions blood and tissue components. Increased permeability of this monolayer leads to leakage of fluid and macromolecules into lung tissue from the blood stream. If this leakage is not stopped it will lead to lung injury. Currently, there are no effective treatments for this problem. We believe that characterization of an important calcium channel in endothelial cells, TRPC6 will provide valuable insights to help us develop therapeutic strategies to reverse the vascular leakiness and thereby lung injury.

描述（由申请人提供）：肺血管内皮通透性增加导致液体和血浆蛋白渗漏到肺组织中，这是急性肺损伤（ALI）发病机制的主要因素。我们的研究将调查一个基本问题：瞬时受体电位阳离子通道 6 (TRPC6)（一种受体操纵通道 (ROC)）介导的 Ca2+ 进入是内皮通透性增加的关键决定因素。我们将检验以下假设：TRPC6 激活对于介导肺血管通透性增加的内皮收缩是必要的且足够的。拟议的研究将使用激动剂凝血酶，它激活内皮细胞表面的蛋白酶激活受体（PAR-1）并产生二酰基甘油，TRPC6通道的直接激活剂。研究将确定双重脂质/蛋白磷酸酶 PTEN 在 TRPC6 激活机制中的作用。我们将探讨 TRPC6 介导的细胞内 Ca2+ 增加的作用，作为 RhoA 和 MLCK-L 激活信号传导的必要条件，从而促进内皮细胞收缩。我们的具体目标是确定 1) 内皮 ROC、TRPC6 在介导 Ca2+ 信号依赖性肺微血管通透性增加中的作用，2) PTEN 介导的 TRPC6 激活机制及其在内皮屏障功能调节中的影响，以及 3) 下游TRPC6诱导肺内皮通透性增加的信号机制涉及PKCa和p60Src激酶以及效应器RhoA和MLCK-L的激活同工型。这些研究将在多个层面上进行，包括利用携带特定基因缺失的小鼠的内皮细胞和肺。我们希望该提案将为开发针对 TRPC6 的治疗策略提供新的见解，从而防止肺血管“渗漏”。公共健康相关性：半选择性内皮细胞单层分隔血液和组织成分。该单层的渗透性增加导致液体和大分子从血流渗漏到肺组织中。如果不阻止这种泄漏，将会导致肺部损伤。目前，这个问题还没有有效的治疗方法。我们相信，内皮细胞中重要钙通道 TRPC6 的表征将为我们提供宝贵的见解，帮助我们制定逆转血管渗漏进而逆转肺损伤的治疗策略。