MECHANISMS OF ISCHEMIC INJURY AND REPAIR

描述(由申请人提供)：拟议研究的总体目标 对缺血性肾细胞损伤和修复机制的了解尚不清楚 有一个长远的目标，就是建立对预防 治疗人类的急性肾功能衰竭(ARF)。在过去的支持期间，我们 已经开发并测试了缺血性ARF是一种疾病的假设 白细胞-内皮细胞的相互作用，特别是在外髓 肾，导致小血管充血和氧合受损 分娩时会导致肾小管细胞损伤。损伤的小管并被激活 内皮细胞通过产生额外的血管损害 细胞因子和趋化因子上调黏附受体并吸引 白细胞。我们最近建立了三个小鼠模型，在这些模型中，肾脏 对缺血损伤有保护作用。这些模型将被利用来 评估假说并确定候选的重要蛋白质 造成伤害的因素或内生的保护过程。在特定目标中1 我们将使用针对缺血损伤的保护模型来定义 外髓质白细胞和内皮细胞活化的重要性 缺血性急性肾功能衰竭病理生理学的相互作用。国家 S3片段的分化和应激反应的评估将被评估为 把改变的潜在重要性放在背景中 白细胞-血管内皮细胞相互作用与易感性改变的关系 近端小管上皮细胞损伤。黏附分子与趋化因子 我们将研究肾脏损伤的潜在作用。 白细胞-上皮细胞相互作用中的分子-1(Kim-I)。在具体目标2中，我们 将评估NMB对白细胞功能的作用并确定其他 与炎症有关的候选基因可能对缺血性脑缺血很重要 肾脏外髓内的损伤或可诱导的保护性突起。我们 将确定NMB及其三个潜在功能域的作用 (多囊肾[PKD]结构域，以及YXXphi和二亮氨酸结构域 胞浆尾巴)对白细胞与血管内皮细胞结合的影响 吞噬作用。基因表达分析将通过转录本进行 与基因数据库查询耦合的简档分析。我们将识别出那些 在我们有三个条件下显示协调上调或下调 经鉴定可保护肾脏免受缺血损伤。 免疫细胞化学、原位杂交、激光捕获显微切割和 TaqMan实时RT-PCR将用于鉴定其基因亚群 缺血后外周血中表达模式的差异调控 比较受保护的肾脏和未受保护的肾脏时的髓质。

DESCRIPTION (provided by applicant): The overall goal of the proposed studies remains to understand the mechanisms of ischemic kidney cell injury and repair with a long range goal to establish therapies that will be useful to prevent and treat acute renal failure (ARF) in man. Over the last support period we have developed and tested the hypothesis that ischemic ARF is a disease in which leukocyte-endothelial interactions, particularly in the outer medulla of the kidney, lead to congestion of the small vessels and impaired oxygen delivery with resultant tubule cell injury. The damaged tubule and activated endothelium contributes to additional vascular compromise by producing cytokines and chemokines which up regulate adhesion receptors and attract leukocytes. We have recently established three mouse models in which the kidney is protected against ischemic injury. These models will be exploited to evaluate the hypothesis and identify proteins that are candidates as important contributors to injury or endogenous processes of protection. In Specific Aim 1 we will use models of protection against ischemic injury to define the importance of outer medullary leukocyte and endothelial activation and interactions for the pathophysiology of ischemic acute renal failure. The state of differentiation and stress response of the S3 segment will be evaluated to put into context the potential importance of alterations in leukocyte-endothelial interactions relative to change in susceptibility to injury of the proximal tubule epithelial cell. Adhesion molecule and chemokine involvement will be studied as will the potential role of Kidney Injury Molecule-1 (KIM-I) in leukocyte-epithelial interactions. In Specific Aim 2 we will evaluate the role of nmb on leukocyte function and identify additional candidate genes implicated in inflammation that may be important for ischemic injury or inducible protective processes in the outer medulla of the kidney. We will determine the effect of nmb and three of its potential functional domains (the polycystic kidney [PKD] domain, and the YXXphi and di-leucine domains in the cytosolic tail) on binding of leukocytes to endothelial cells and on phagocytosis. Gene expression analyses will be performed by transcript profiling coupled to a gene database query. We will identify those genes that show coordinate up or down regulation under three conditions that we have identified to result in protection of the kidney against ischemic injury. Immunocytochemistry, in situ hybridization, laser capture microdissection and TaqMan real time RT-PCR will be used to identify that subgroup of genes whose expression pattern is differentially regulated in the postischemic outer medulla when comparing protected vs non-protected kidneys.