PARs and S1P receptors in endothelial biology

内皮生物学中的 PAR 和 S1P 受体

• 批准号: 8279302
• 负责人: SHAUN R. COUGHLIN
• 金额: $ 55.81万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-09-30 至 2014-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8279302
• 关键词: Adult; Affect; Allergic Reaction; Anaphylaxis; Anatomy; Apical; Atherosclerosis; Autocrine Communication; Basement membrane; Biology; Blood Platelets; Blood Vessels; Cardiovascular system; Cell Culture Techniques; Cell Line; Cell membrane; Cell physiology; Cells; Coagulation Process; Complex; Development; Disease; Embryo; Embryonic Development; Employee Strikes; Endothelial Cells; Exhibits; Extravasation; Failure; Functional disorder; G Protein-Coupled Receptor Genes; G-Protein-Coupled Receptors; Genes; Genetic; Goals; Growth; Health; In Vitro; Inflammatory; Injury; Knockout Mice; Laboratories; Leukocytes; Ligation; Long-Term Effects; Maintenance; Malignant Neoplasms; Metabolic; Metabolism; Modeling; Molecular; Mus; Myocardial Infarction; Patients; Peptide Hydrolases; Permeability; Phosphotransferases; Physiology; Plasma; Play; Property; Proteinase-Activated Receptors; Receptor Activation; Receptor Signaling; Regulation; Role; Sepsis; Signal Pathway; Signal Transduction; Source; Specificity; Sphingosine; Sphingosine-1-Phosphate Receptor; Stroke; Surface; System; Testing; Thrombus; Tissues; Toxic effect; Transgenic Organisms; Vascular Permeabilities; base; cell type; detector; edg-1 Protein; in vivo; monolayer; mouse model; receptor; receptor function; response; sphingosine 1-phosphate; sphingosine kinase

DESCRIPTION (provided by applicant): We will characterize two signaling systems that regulate the permeability and integrity of blood vessels: coagulation proteases and protease-activated receptors, and sphingosine-1-phosphate and S1P receptors. We will test the hypothesis that both systems sense extravasation of plasma and trigger appropriate endothelial cell responses, and we will explore parallels and possible connections between these systems. We shall ask: 1) How is S1P important for regulation of vascular permeability and integrity? We generated adult mice that fail to supply S1P to plasma and found striking abnormalities in vascular permeability and integrity. We shall determine a) whether altered barrier function in these "pS1Pless" mice is due to failure to metabolize sphingosine with consequent endothelial cell-autonomous metabolic/toxic effects or to failure to supply S1P to plasma and S1P receptor activation on endothelial and other cells, b) the anatomic basis for their increased vascular leak and whether it shows tissue or vessel-type specificity, c) whether endothelial cells are the main target of plasma S1P signaling in this context, and if so, whether such signaling is continuous or whether plasma S1P provides a dynamic signal that enables endothelial cells to sense and help terminate leaks, and d) the long-term effects of lack of plasma S1P and whether they are due to dysregulated barrier function. 2) How are PARs important for regulation of vascular permeability and integrity? We generated knockout mice for all the PARs and relevant transgenics and will use these to determine a) the effects of activation of different endothelial PARs on vascular permeability and integrity in vivo and whether pS1Pless mice provide a sensitized system for uncovering such roles for PARs, b) whether PAR signaling is parallel to, partially redundant with, or dependent upon S1P signaling. 3) Do differences in apical and basal S1P and PAR function contribute to their roles in barrier regulation? Our preliminary studies suggest a model that would permit S1P signaling to serve a dynamic leak detector function and raise new questions regarding PARs by analogy. We will determine a) whether endothelial cell S1P1 receptors display apical-basal polarity in vitro and in vivo to enable the dynamic leak detecting function we posit, and b) whether apical and basal differences, such as EPCR ligation, modulate the effects of PAR activation on either surface. Complementary genetic and pharmacological approaches will be used in mouse models and in cell culture. Preliminary studies reveal an important role for plasma S1P in regulating endothelial barrier function in vivo, distinct barrier responses to activation of different PARs, dramatic effects of manipulation of S1P and PAR signaling on survival in models of anaphylaxis, and long-term effects of altered barrier function in vivo. The proposed studies will provide new information regarding vascular physiology and pathophysiology. PUBLIC HEALTH RELEVANCE: Our studies will reveal new molecular and cellular mechanisms by which the endothelial cells that line blood vessels sense and regulate leakiness. Alterations in endothelial permeability play an important role in allergic reactions, new blood vessel growth in cancer, heart attacks and strokes, atherosclerosis, and inflammatory states including sepsis. Thus, understanding of how to manipulate the endothelial leakiness might benefit patients with a range of disorders.

描述（由申请人提供）：我们将表征调节血管渗透性和完整性的两种信号系统：凝血蛋白酶和蛋白酶激活受体，以及鞘氨醇-1-磷酸和S1 P受体。我们将检验这两个系统感知血浆外渗并触发适当的内皮细胞反应的假设，我们将探索这些系统之间的相似之处和可能的联系。我们将问：1）S1 P对调节血管通透性和完整性有何重要性？我们产生了成年小鼠，不能供应S1 P的血浆，并发现血管通透性和完整性显着异常。我们将确定a）这些“pS1 P缺乏”小鼠中屏障功能的改变是否是由于鞘氨醇代谢失败而导致内皮细胞自主代谢/毒性效应，或者是由于不能向血浆提供S1 P以及内皮细胞和其他细胞上的S1 P受体活化，B）其血管渗漏增加的解剖学基础以及其是否显示组织或血管类型特异性，c）在这种情况下，内皮细胞是否是血浆S1 P信号传导的主要靶标，如果是，这种信号传导是否是连续的，或者血浆S1 P是否提供使内皮细胞能够感知并帮助终止渗漏的动态信号，和d）缺乏血浆S1 P的长期影响以及它们是否是由于屏障功能失调。2)PAR对调节血管通透性和完整性有何重要性？我们产生了所有PAR和相关转基因的敲除小鼠，并将使用这些小鼠来确定a）不同内皮PAR的激活对体内血管通透性和完整性的影响，以及无pS1 P的小鼠是否提供了揭示PAR这种作用的致敏系统，B）PAR信号传导是否与S1 P信号传导平行、部分冗余或依赖于S1 P信号传导。3)顶端和基底S1 P和PAR功能的差异是否有助于它们在屏障调节中的作用？我们的初步研究提出了一个模型，将允许S1 P信号服务于动态泄漏检测器功能，并提出了新的问题，通过类比PAR。我们将确定a）内皮细胞S1 P1受体是否在体外和体内显示顶-底极性，以实现我们所研究的动态渗漏检测功能，以及B）顶和底差异（如EPCR连接）是否调节PAR激活对任一表面的影响。互补的遗传和药理学方法将用于小鼠模型和细胞培养。初步研究揭示了血浆S1 P在体内调节内皮屏障功能中的重要作用，对不同PAR激活的不同屏障反应，操纵S1 P和PAR信号对过敏反应模型中存活的显著影响，以及体内屏障功能改变的长期影响。拟议的研究将提供有关血管生理学和病理生理学的新信息。公共卫生关系：我们的研究将揭示新的分子和细胞机制，通过这些机制，血管内皮细胞感知和调节泄漏。内皮渗透性的改变在过敏反应、癌症中的新血管生长、心脏病发作和中风、动脉粥样硬化和炎症状态（包括败血症）中起重要作用。因此，了解如何操纵内皮渗漏可能会使患有一系列疾病的患者受益。