Injury - Induced Endothelial Dysfunction

描述（由申请方提供）：以内皮（EC）损伤为特征的疾病是手术发病率的主要原因，并代表了一个重大的公共卫生问题。它们包括创伤后炎症和感染综合征，如全身炎症反应综合征（SIRS）、多器官功能障碍（MOD）和急性呼吸窘迫综合征（ARDS）。初步研究表明，内皮粘附连接的磷酸化和解离，结合内皮收缩，可能是导致EC屏障功能障碍的介质的最终共同途径。导致交界磷酸化和解离的机制尚不清楚，包括氧化剂、rho途径、MAPK和Src激酶的作用。我们的目标是确定调节连接分离和EC收缩的主要途径。主要的实验问题包括了解细胞内氧化剂的酶源及其在连接磷酸化中的作用，并确定EC收缩过程中EC屏障功能调节的细胞骨架的作用。我们的中心假设是，由肿瘤坏死因子-α（TNF）诱导的EC氧化剂产生最终导致粘附连接蛋白的酪氨酸磷酸化和EC收缩;这两个事件一起削弱粘附连接，导致连接解离和细胞间间隙形成。总体目标是确定细胞内氧化剂、rho和MAPK通路对连接磷酸化和内皮功能障碍的作用。

DESCRIPTION (provided by applicant): Diseases characterized by endothelial (EC) injury are a major cause of surgical morbidity and represent a significant public health problem. They include post-traumatic inflammatory and infectious syndromes, such as systemic inflammatory response syndrome (SIRS), multiple organ dysfunction (MOD) and acute respiratory distress syndrome (ARDS). Preliminary studies suggest that phosphorylation and dissociation of endothelial adherens junctions, combined with endothelial retraction, may represent the final common pathway for mediators that cause EC barrier dysfunction. Less clear are the mechanisms that lead to junctional phosphorylation and dissociation, including the role of oxidants, rho pathways, MAPK and Src kinases. Our objective is to identify the dominant pathways that regulate junctional dissociation and EC retraction. Major experimental problems include understanding the enzymatic source of intracellular oxidants and their role in junctional phosphorylation, and determining the role of the cytoskeleton in EC retraction during regulation of EC barrier function. Our central hypothesis is that EC oxidant production induced by tumor necrosis factor-alpha (TNF) ultimately results in tyrosine phosphorylation of adherens junction proteins and EC retraction; both events together weaken the adherens junction, causing junctional dissociation and intercellular gap formation. The overall objectives are to determine the role of intracellular oxidants, rho and MAPK pathways on junctional phosphorylation and endothelial dysfunction.