INJURY AND REPAIR MECHANISMS IN ACUTE RENAL FAILURE

急性肾功能衰竭的损伤和修复机制

基本信息

批准号：
2709016
负责人：
Timothy Alan Sutton
金额：
$ 3.7万
依托单位：
INDIANA UNIV-PURDUE UNIV AT INDIANAPOLIS
依托单位国家：
美国
项目类别：
财政年份：
1999
资助国家：
美国
起止时间：
1999-02-05 至
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/2709016
关键词：
acute renal failure biological signal transduction cell adhesion cell line confocal scanning microscopy disease /disorder model guanine nucleotide binding protein molecular pathology myosin light chain kinase myosins phosphorylation stoichiometry transfection western blottings

项目摘要

Epithelial cell structure and function depend on an intact cytoskeleton. It is known that alterations in the actin cytoskeleton during periods of ischemic injury and recovery have important consequences for cell and organ function. This is especially true of the renal proximal tubule epithelia which is the predominant site of injury in human ischemic acute renal failure. One of the dramatic consequences of these alterations is the loss of cell adhesion to the underlying tissue matrix. Myosin II is felt to play a key role in organizing the actin cyctyskeleton in areas of the cell critical to cell-matrix adhesion and thus cell and organ function. The regulatory processes involved in these alterations have not been well characterized; however, the Rho family GTPases have been shown to play a role in regulating distinct aspects of cytoskeletal rearrangement involved in normal cellular function. The overall hypothesis of this study is that myosin II activation is an important distal effector of the Rho regulatory cascade and plays a critical role in controlling the actin cytoskeleton during ischemia and recovery. We propose to evaluate the level of myosin activation during ATP depletion and recovery in a reversible cell culture model of ATP depletion that recapitulates the changes observed in ischemic acute renal failure. We plan to relate changes in myosin activation during ATP depletion and recovery with the number of actin stress fibers which are involved in focal adhesion complexes and cell matrix adhesion. We also propose to use recombinant forms of Rho, Rho- kinase, and MLCK which are dominantly active and negative to begin to determine the regulatory mechanisms involved in control of myosin II in epithelial cells during ATP depletion and recovery. Taken together these studies should provide new and important information about the mechanisms regulating pathologic rearrangements of the cytoskeleton in epithelial cells during ischemia.

上皮细胞结构和功能取决于完整细胞骨架。众所周知，肌动蛋白细胞骨架的改变在缺血性损伤期间，恢复很重要细胞和器官功能的后果。尤其如此肾近端小管上皮菌是主要部位人缺血性急性肾衰竭的损伤。戏剧性的之一这些改变的后果是细胞粘附对基础组织基质。肌球蛋白II在在细胞区域内组织肌动蛋白cyctyctysketormon至关重要细胞 - 矩阵粘附，因此细胞和器官功能。这这些改变涉及的监管过程还不太好特征;但是，Rho家族GTPases已被证明在调节细胞骨架的不同方面发挥作用重排参与正常细胞功能。总体这项研究的假设是肌球蛋白II激活是重要的 Rho调节级联的远端效应子，并扮演关键缺血期间控制肌动蛋白细胞骨架的作用恢复。我们建议评估肌球蛋白激活的水平在可逆细胞培养模型中的ATP耗竭和恢复期间概括缺血性变化的ATP耗竭急性肾衰竭。我们计划关联肌球蛋白激活的变化在ATP耗竭和恢复过程中，肌动蛋白应力数量涉及焦点粘附复合物和细胞基质的纤维粘附。我们还建议使用重组形式的Rho，Rho- 激酶和MLCK主要是活跃的，负面的确定控制肌球蛋白II的调节机制在ATP耗竭和恢复期间上皮细胞中。拍摄这些研究共同提供新的重要信息关于调节病理重排的机制缺血期间上皮细胞中的细胞骨架。