Intracellular S1P & signaling in lung endothelial cells

细胞内S1P

基本信息

批准号：
7325784
负责人：
VISWANATHAN NATARAJAN
金额：
$ 34.1万
依托单位：
UNIVERSITY OF CHICAGO
依托单位国家：
美国
项目类别：
财政年份：
2004
资助国家：
美国
起止时间：
2004-12-01 至 2009-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7325784
关键词：
Address Agonist Angiogenesis Inducing Agents Apoptosis Arteries Asthma Atherosclerosis Blood Circulation Blood Platelets Calcium Cell Adhesion Molecules Cell physiology Cells Chemotactic Factors Chemotaxis Condition Coupled Cytoskeletal Modeling Data Endothelial Cells Endothelium Enzymes Equilibrium Exposure to Family G-Protein-Coupled Receptors GTP-Binding Proteins Generations Homeostasis Homing Human Hydrolysis IL8 gene Immunosuppressive Agents Intracellular Second Messenger Ligands Lipids Lung Lymphocyte Mammalian Cell Mediating Molecular Pathway interactions Pharmaceutical Preparations Phorbol Esters Phosphoric Monoester Hydrolases Phosphorylation Physiological Plasma Play Process Production Protein Dephosphorylation Proteins Receptor Gene Regulation Research Personnel Role Second Messenger Systems Signal Transduction Source Sphingosine Stimulus TNF gene Thrombin Wound Healing angiogenesis cell growth cell motility cellular targeting extracellular immunoregulation inorganic phosphate insight lipid mediator lipid phosphate phosphatase mast cell novel programs receptor receptor binding research study second messenger sphingosine 1-phosphate sphingosine kinase

项目摘要

DESCRIPTION (provided by applicant): Sphingosine-1-phosphate (S1P), a bioactive lipid mediator, not only acts as an extra-cellular ligand for the G-protein coupled SIP 1-5 receptors (formerly known as endothelial differentiation gene receptors), but also functions as an intra-cellular second messenger involved in Ca2+ mobilization, proliferation and suppression of apoptosis. Earlier, we and others have demonstrated that platelet derived and exogenously added S1P enhance endothelial barrier function and chemotaxis. Our preliminary experiments suggest that human lung endothelial cells (ECs) rapidly convert exogenous and plasma-derived S1P to intra-cellular S1P; however, it is unclear the molecular mechanisms of intra-cellular S1P signaling that regulate key EC functions. Recently, several lipid phosphate phosphatases (LPPs) and two sphingosine kinases (Sphks) have been cloned and characterized in mammalian cells which may regulate the dynamic balance between extra- and intra-cellular S1P levels. This proposal will address the role of LPPs and Sphks in regulating endothelial calcium homeostasis, proliferation and cytoskeletal reorganization. It is postulated that "LPPs and Sphks regulate intra-cellular generation and signaling of S1P in human lung ECs. Specific Aim 1 will characterize the LPPs and their role in regulating intra-cellular S1P production in the endothelium. Specific Aim 2 will determine the role and regulation of Sphks 1 and 2 in catalyzing the phosphorylation of sphingosine derived by the action of the LPPs on exogenous S1P. Specific Aim 3 will address the cellular targets and functions of intra-cellular S1P. Taken together, these experiments will uncover novel mechanisms by which LPPs and Sphks regulate production of intra-cellular S1P from circulating plasma and also identify intra-cellular targets of S1P involved in calcium homeostasis, secretion, and expression of adhesion molecules, chemotaxis, and wound healing in lung endothelial cells. A better understanding of molecular mechanisms of regulation of LPPs and Sphks in mediating intra-cellular formation of S1P from circulation will provide new insights into possible physiological role of S1P as an intra-cellular second messenger in lung endothelial cells under normal and pathological conditions such as atherosclerosis and asthma.

描述（申请人提供）：1-磷酸鞘氨醇 (S1P) 是一种生物活性脂质介质，不仅充当 G 蛋白偶联 SIP 1-5 受体（以前称为内皮分化基因受体）的细胞外配体，而且还作为细胞内第二信使参与 Ca2+ 动员、增殖和细胞凋亡的抑制。早些时候，我们和其他人已经证明血小板衍生的和外源添加的 S1P 增强内皮屏障功能和趋化性。我们的初步实验表明，人肺内皮细胞 (EC) 能够快速将外源性和血浆来源的 S1P 转化为细胞内 S1P；然而，目前尚不清楚调节关键 EC 功能的细胞内 S1P 信号传导的分子机制。最近，在哺乳动物细胞中克隆并鉴定了几种脂质磷酸酶（LPP）和两种鞘氨醇激酶（Sphks），它们可能调节细胞外和细胞内S1P水平之间的动态平衡。该提案将探讨 LPP 和 Sphk 在调节内皮钙稳态、增殖和细胞骨架重组中的作用。据推测，“LPP 和 Sphk 调节人肺 EC 中 S1P 的细胞内生成和信号传导。具体目标 1 将描述 LPP 及其在内皮细胞中调节细胞内 S1P 生成中的作用。具体目标 2 将确定其作用以及 Sphks 1 和 2 在催化由 LPP 对外源 S1P 作用产生的鞘氨醇磷酸化过程中的调节。目标 3 将解决细胞内 S1P 的细胞靶标和功能总而言之，这些实验将揭示 LPP 和 Sphks 调节循环血浆中细胞内 S1P 产生的新机制，并鉴定参与的 S1P 细胞内靶标。肺内皮细胞中钙稳态、粘附分子的分泌和表达、趋化性和伤口愈合更好地了解 LPP 和 Sphk 介导的分子机制。循环中 S1P 的细胞内形成将为了解 S1P 在正常和病理条件下（如动脉粥样硬化和哮喘）作为肺内皮细胞的细胞内第二信使的可能生理作用提供新的见解。