Intersectin-1s regulates lung vascular permeability and endothelial cell survival

Intersectin-1s 调节肺血管通透性和内皮细胞存活

• 批准号: 7386496
• 负责人: Sanda A Predescu
• 金额: $ 37万
• 依托单位: RUSH UNIVERSITY MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-03-01 至 2013-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7386496
• 关键词: Acute; Acute Lung Injury; Address; Adult Respiratory Distress Syndrome; Albumins; Apoptosis; Apoptotic; Binding Sites; Biochemical; Blood Vessels; Caveolae; Cell Death; Cell Survival; Cell membrane; Cessation of life; Characteristics; Chemicals; Coiled-Coil Domain; Complement; Complex; Data; Down-Regulation; Dynamin; Electron Microscopy; Elements; Endocytosis; Endothelial Cells; Endothelium; Figs - dietary; Functional disorder; Guanosine Triphosphate; Guanosine Triphosphate Phosphohydrolases; Hydrolysis; Impairment; Injury; Link; Lung; Lung diseases; Mediating; Microvascular Permeability; Mitochondria; Molecular; Molecular Biology; Mus; Neck; Newborn Respiratory Distress Syndrome; Numbers; Pathway interactions; Permeability; Phosphorylation; Phosphotransferases; Play; Proline-Rich Domain; Property; Protein Family; Protein Overexpression; Proteins; RNA Interference; Range; Ras/Raf; Recruitment Activity; Regulation; Role; SH3 Domains; Scaffolding Protein; Secondary to; Signal Pathway; Signal Transduction; Site; Structure; Testing; Vascular Permeabilities; Work; alveolar destruction; base; insight; intersectin 1; knock-down; lung injury; novel; platelet protein P47; protein expression; therapeutic target; trafficking; transcytosis

DESCRIPTION (provided by applicant): Abnormalities in caveolae and lung endothelial cell (ECs) function may result in alterations of lung vascular permeability. This may be a key element of the complex pathophysiology underlying acute lung injury. The understanding of the molecular mechanisms that regulate caveolae-mediated transcytosis and its role in mediating increased lung microvessel endothelial permeability are unclear. Our Supporting Data suggest that the crucial scaffold protein in lung ECs, intersectin-1s (ITSN-1s), plays an important role in caveolae trafficking through its interaction with dynamin and other key proteins regulating endothelial permeability. Our Supporting Data suggest that ITSN-1s is crucial in recruiting dynamin at the neck region of caveolae and that dynamin presence at the endocytic site and its ability to hydrolyze GTP are essential for caveolae release from the plasma membrane during caveolae transcytosis. However, the relationship between ITSN-1s and dynamin and its significance in the mechanism of increased lung vascular endothelial permeability are not yet defined. Strikingly, ECs deficient in ITSN-1s became apoptotic by activation of the mitochondrial death pathway through a mechanism that involves inactivation of the survival kinase Erk1/2. Thus, besides regulating transcytosis, ITSN-1s is also an anti-apoptotic protein that may have consequences in mediating lung microvascular injury secondary to apoptosis of ECs. The central hypothesis of the proposed studies is that ITSN-1s is a pivotal protein mediating the cross-talk between caveolae endocytosis and signaling pathways that regulates lung vascular endothelial permeability and EC survival. The following specific aims will test this hypothesis: Specific Aim 1 will define the role of ITSN-1s, via its SH3 domains, as a regulator of dynamin function. Specific Aim 2 will address the functional significance of ITSN-1s/dynamin interaction in the mechanism of caveolae release from the plasma membrane of lung microvessel ECs and in regulating lung microvascular permeability in mice. Specific Aim 3 will delineate the signaling mechanisms controlled by ITSN-1s that defend lung endothelium against apoptotic cell death and lung vascular endothelial injury. With the successful completion of the aims, we hope to provide novel insights into the i) pivotal role of the SH3 domains of ITSN-1s in regulation of dynamin function in lung microvessel ECs, ii) functional significance of ITSN/dynamin interaction in caveolae endocytosis and lung endothelial barrier function, and iii) signaling pathways and mechanisms governing the anti-apoptotic effects of ITSN-1s in ECs and its pathophysiological consequence in the mechanism of lung microvascular injury. We hope to provide a novel understanding of transcytosis and its regulation of lung vascular endothelial permeability and specific molecular therapeutic targets directed against inappropriate leakiness of the lung microvascular barrier. This study will provide novel insights regarding i) the role of intersectin-1s in regulation of lung vascular endothelial permeability and ii) the signaling pathways and mechanisms governing the anti-apoptotic effects of intersectin-1s in endothelial cells. Confirming intersectin-1s as a link between microvascular permeability, apoptosis and lung disease, we may find new targets against inappropriate leakiness of the lung microvascular barrier and slow the alveolar destruction associated with acute respiratory distress syndrome (ARDS) and acute lung injury (ALI).

描述（由申请人提供）：小窝和肺内皮细胞（EC）功能的异常可能导致肺血管通透性的改变。这可能是急性肺损伤复杂病理生理学的关键要素。对调节小凹介导的转胞吞作用的分子机制及其在介导肺微血管内皮通透性增加中的作用尚不清楚。我们的支持数据表明，肺内皮细胞中关键的支架蛋白 intersectin-1s (ITSN-1s) 通过与动力和其他调节内皮通透性的关键蛋白相互作用，在细胞膜穴运输中发挥重要作用。我们的支持数据表明，ITSN-1s 对于在小窝颈部区域招募动力至关重要，并且内吞位点的动力存在及其水解 GTP 的能力对于小窝转胞吞期间从质膜释放小窝至关重要。然而，ITSN-1与dynamin之间的关系及其在肺血管内皮通透性增加机制中的意义尚不清楚。引人注目的是，缺乏 ITSN-1 的 EC 通过一种涉及生存激酶 Erk1/2 失活的机制激活线粒体死亡途径而发生凋亡。因此，除了调节转胞吞作用外，ITSN-1s 也是一种抗凋亡蛋白，可能在介导 EC 凋亡继发的肺微血管损伤中产生影响。拟议研究的中心假设是，ITSN-1s 是介导小窝内吞作用和调节肺血管内皮通透性和 EC 存活的信号通路之间串扰的关键蛋白。以下具体目标将检验这一假设： 具体目标 1 将通过其 SH3 结构域定义 ITSN-1 作为动力功能调节器的作用。具体目标 2 将解决 ITSN-1s/动力相互作用在肺微血管 EC 质膜释放小窝机制和调节小鼠肺微血管通透性的机制中的功能意义。具体目标 3 将描述由 ITSN-1 控制的信号机制，保护肺内皮免受细胞凋亡和肺血管内皮损伤。随着这些目标的成功完成，我们希望对 i) ITSN-1s 的 SH3 结构域在肺微血管 EC 动力功能调节中的关键作用，ii) ITSN/动力相互作用在小凹胞吞作用和肺内皮屏障功能中的功能意义，以及 iii) 控制 ITSN-1s 抗凋亡作用的信号通路和机制提供新的见解。 ECs 及其在肺微血管损伤机制中的病理生理学后果。我们希望对转胞吞作用及其对肺血管内皮通透性的调节以及针对肺微血管屏障不适当渗漏的特定分子治疗靶标提供新的理解。这项研究将为 i) intersectin-1s 在调节肺血管内皮通透性中的作用和 ii) 控制 intersectin-1s 在内皮细胞中的抗凋亡作用的信号通路和机制提供新的见解。确认 intersectin-1s 是微血管通透性、细胞凋亡和肺部疾病之间的联系，我们可能会找到对抗肺微血管屏障不适当渗漏的新靶点，并减缓与急性呼吸窘迫综合征 (ARDS) 和急性肺损伤 (ALI) 相关的肺泡破坏。