Mechanisms of Prostacyclin-Mediated Lung Endothelial Barrier Protection

前列环素介导的肺内皮屏障保护机制

• 批准号: 8529595
• 负责人: Konstantin Birukov
• 金额: $ 37.6万
• 依托单位: UNIVERSITY OF CHICAGO
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-07-01 至 2016-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8529595
• 关键词: Acceleration; Actins; Acute; Acute Lung Injury; Address; Adhesions; Adhesives; Adult Respiratory Distress Syndrome; Affect; Aftercare; Air; Animal Model; Automobile Driving; Bacteria; Blood Vessels; Blood gas; CCM1 gene; Cell Adhesion; Cell Adhesion Molecules; Cell Culture Techniques; Cell physiology; Cell-Matrix Junction; Cells; Complex; Cyclic AMP; Cytoskeleton; Development; Down-Regulation; Drug Design; Endothelial Cells; Experimental Models; FDA approved; Functional disorder; Future; Genetic Models; Guanosine Triphosphate Phosphohydrolases; Heating; IL8 gene; Iloprost; In Vitro; Inflammation; Inflammatory; Injury; Intercellular Junctions; Intercellular adhesion molecule 1; Intervention; Knowledge; Liquid substance; Lung; Lung Inflammation; Mediating; Modeling; Molecular; Molecular Target; Morbidity - disease rate; Mus; Neutrophil Infiltration; Pathway interactions; Peripheral; Permeability; Pharmaceutical Preparations; Pharmacotherapy; Phase; Phenotype; Play; Pre-Clinical Model; Prevention; Preventive; Process; Production; Prostaglandins I; Protective Agents; Proteins; Pulmonary Edema; Recovery; Regulation; Resolution; Respiratory physiology; Role; Scheme; Signal Transduction; Staphylococcus aureus; Structure; Testing; Time; Vascular Endothelial Cell; Vascular Permeabilities; Ventilator-induced lung injury; analog; attenuation; clinically relevant; cytokine; drug testing; effective therapy; gain of function; in vivo; loss of function; lung injury; monolayer; mortality; neutrophil; novel; protective effect; repaired; research study; restoration; rho; rho GTP-Binding Proteins; septic; vascular endothelial dysfunction; vascular inflammation

DESCRIPTION (provided by applicant): Development of effective therapies for treatment of acute lung injury (ALI) and adult respiratory distress syndrome (ARDS) remains a challenging task. Many experimental models for testing of novel protective agents utilize preventive or concurrent treatment during ALI induction, while post-treatment represents more clinically relevant intervention. Such differences in the timing of drug administration may have dramatic impact on the efficiency of treatment and activation of specific molecular mechanisms directing resolution of ongoing injury in contrast to blocking onset of ALI by drug pretreatment. This proposal will fill this void and explore effects of post-treatment with FDA-approved prostacyclin (PC) analog iloprost in the in vitro and in vivo septic ALI models. Inflammation and increased endothelial cell (EC) permeability play a major role in the pathophysiology of ALI. During the previous cycle of this proposal, we characterized for the first time the molecular mechanisms of PC-mediated protection in aseptic model of ventilator induced lung injury. Our preliminary studies suggest potent protective effects of PC pretreatment against LPS-induced lung inflammation and vascular leak. This proposal will investigate effects of PC post-treatment in cell culture and animal models of septic ALI caused by Gram-positive heat-inactivated Staphylococcus Aureus bacteria (HKSA). We hypothesize that signaling by Rap1 GTPase plays a dual role in PC-induced acceleration of ALI resolution via promotion of EC barrier repair and suppression of inflammatory endothelial activation. Aim-1 will evaluate effects of PC post-treatment and define a role of Rap1 in acceleration of barrier recovery in HKSA challenged EC. Aim-2 will define molecular mechanisms downstream of Rap1 involved in EC barrier recovery. We will study a role of Rap1 effectors KRIT1 and RIAM in enhancement of EC adhesive structures and peripheral cytoskeleton essential for re-establishment of EC barrier. Aim-3 will study a role of Rap1, KRIT1 and RIAM stimulation by PC post-treatment in downregulation of HKSA-induced pulmonary EC activation. Aim-4 will elucidate specific role of Rap1, KRIT1 and Riam in PC-facilitated ALI recovery in vivo using "loss of function" and "gain of function" molecular approaches and mouse genetic models. These studies will characterize novel protective mechanisms and identify new protein targets for future therapies aimed at prevention of the pulmonary vascular barrier dysfunction associated with acute lung injury.

描述（由申请人提供）：开发用于治疗急性肺损伤（ALI）和成人呼吸窘迫综合征（ARDS）的有效疗法仍然是一项艰巨的任务。许多用于测试新型保护剂的实验模型在ALI诱导过程中采用预防或并发治疗，而治疗后则代表更临床相关的干预措施。药物给药时间的这种差异可能对治疗效率和激活的特定分子机制的激活可能产生巨大影响，这与通过药物预处理阻止ALI的发作相反。该提案将用FDA批准的前列腺素（PC）类似物伊洛列前列体在体外和体内化粪池Ali模型中使用FDA批准的前列腺素（PC）类似物依依前列体填充这种空白并探索后处理的影响。炎症和内皮细胞增加（EC）渗透率在ALI的病理生理学中起主要作用。在该提案的上一个周期中，我们首次表征了PC介导的呼吸机诱导肺损伤的PC介导的保护的分子机制。我们的初步研究表明，PC预处理对LPS引起的肺部炎症和血管泄漏的有效保护作用。该建议将研究PC后处理对革兰氏阳性热灭活金黄色葡萄球菌（HKSA）引起的败血性ALI的细胞培养和动物模型的影响。我们假设RAP1 GTPase的信号通过促进EC屏障修复和抑制炎症内皮激活而在PC诱导的ALI分辨率加速中起双重作用。 AIM-1将评估PC后处理后的影响，并定义RAP1在HKSA挑战EC中加速屏障恢复中的作用。 AIM-2将定义与EC屏障恢复有关的RAP1下游的分子机制。我们将研究RAP1效应子KRIT1和RIAM在增强EC粘合剂结构以及对重新建立EC屏障必不可少的外周细胞骨架中的作用。 AIM-3将研究PC处理后PC刺激RAP1，KRIT1和RIAM刺激在HKSA诱导的肺EC激活下的下调。 AIM-4将使用“函数丧失”和“功能的丧失”和“功能的增益”分子方法和小鼠遗传模型在PC-辅助ALI恢复中阐明RAP1，KRIT1和RIAM的特定作用。这些研究将表征新颖的保护机制，并确定旨在预防与急性肺损伤相关的肺血管屏障功能障碍的未来疗法的新蛋白质靶标。