Disintegrin Metalloprotease and Endothelial Dysfunction in Sepsis

项目摘要/摘要 蛇咬伤患者通常会出现类似脓毒症的症状，如浮肿和呼吸窘迫综合征。 对蛇毒的分析已经鉴定出一类具有去整合素金属蛋白酶特征的蛋白酶家族 (亚当斯)具有切割跨膜分子的能力。我们以前的工作是由这笔赠款支持的 已经专注于这个家族中的一个独特的成员，ADAM15，关于它的分子结构和功能 调节内皮细胞屏障特性。我们报告了ADAM15在肺和血管组织中的上调 在炎症过程中，它通过src-1增加内皮通透性并促进白细胞迁移。 依赖的信号转导由其胞质结构域。在这次续签申请中，我们计划将我们的 通过检测ADAM15高翻译新分子靶点向下一步研究 价值和治疗潜力。这些研究将集中在内皮糖衣，一种屏障保护结构 由连接到跨膜蛋白多糖和糖蛋白的糖胺多糖链组成，它们是 在受伤或大手术后排入血液循环。要检测的中心通路是在脓毒症期间 损伤时，ADAM15裂解这些跨膜分子，导致糖萼降解。曝光率 内皮到循环细胞和试剂，以及作为高渗透因子的脱落产物， 促进血浆渗漏和白细胞渗出。提出了三个具体目标：1)表征 2)阐明ADAM在脓毒症中的分子机制。 导致糖萼降解；以及3)测试靶向ADAM-糖萼的治疗潜力 脓毒症的治疗途径。我们将采用互补的方法，将生理反应 以及器官、组织和细胞水平上的分子反应。创新的实验模型和疗法将是 测试过。一种独特的设计是在临床相关条件下的肺病理生理学特征， 利用由联邦认证的器官提供的可用的完整可存活的人体器官 采购组织。从拟议工作中获得的数据将提供对 脓毒症的分子发病机制。这项研究还将有助于小说的识别和发展 用于治疗与感染、创伤或大手术相关的血管炎症损伤的治疗靶点。

PROJECT SUMMARY/ABSTRACT Snakebite victims often present with sepsis-like symptoms, such as edema and respiratory distress syndrome. Analyses of snake venoms have identified a family of proteases characteristic of disintegrin metalloproteases (ADAMs) with the capability to cleave transmembrane molecules. Our previous work supported by this grant has focused on a unique member of this family, ADAM15, with respect to its molecular structure and function in regulating endothelial barrier property. We reported ADAM15 upregulation in the lungs and vascular tissues during inflammation, where it increases endothelial permeability and promotes leukocyte migration via Src- dependent signaling transduced by its cytoplasmic domain. In this renewal application, we plan to bring our investigation on ADAM15 to the next level by examining its novel molecular targets with high translational values and therapeutic potential. The studies will focus on endothelial glycocalyx, a barrier protective structure composed of glycosaminoglycan chains linked to transmembrane proteoglycans and glycoproteins, which are shed into the circulation following injury or major surgery. The central pathway to be tested is that during septic injury, ADAM15 cleaves these transmembrane molecules leading to glycocalyx degradation. The exposure of endothelium to circulating cells and agents, along with shedding products acting as hyperpermeability factors, promotes plasma leakage and leukocyte diapedesis. Three specific aims are proposed: 1) to characterize ADAM-induced glycocalyx injury during sepsis; 2) to elucidate the molecular mechanisms by which ADAM causes glycocalyx degradation; and 3) to test the therapeutic potential of targeting the ADAM-glycocalyx pathway for treating sepsis. We will employ complementary approaches that integrate physiological responses and molecular reactions at organ, tissue, and cell levels. Innovative experimental models and therapies will be tested. A unique design is the characterization of lung pathophysiology under clinically relevant conditions, taking advantage of the available intact viable human organs provided by a federally certified organ procurement organization. Data derived from the proposed work will provide new mechanistic insights into the molecular pathogenesis of sepsis. The study will also assist in the identification and development of novel therapeutic targets for treating vascular inflammatory injury associated with infection, trauma or major surgery.