Diaphragm Mitochondrial Alterations in Sepsis

脓毒症中的隔膜线粒体改变

• 批准号: 6459357
• 负责人: LEIGH A CALLAHAN
• 金额: $ 35.89万
• 依托单位: UNIVERSITY OF ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-06-01 至 2005-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6459357
• 关键词: Krebs' cycle; bacterial disease; blood toxicology; creatine kinase; diaphragm; electron transport; endotoxins; enzyme activity; enzyme inhibitors; free radical scavengers; gel electrophoresis; glycosides; laboratory rat; lipopolysaccharides; microarray technology; mitochondria; nicotinamide adenine dinucleotide; nitric oxide synthase; oxidative phosphorylation; oxygen consumption; polymerase chain reaction; sarcomeres; spectrometry

DESCRIPTION (Applicant's abstract): Recent work suggests that mitochondria dysfunction plays a central role in sepsis, a major cause of death and morbidity in the United States. The underlying mechanisms responsible for this mitochondria dysfunction are not known. The goal of the present proposal is to test the hypothesis that increased free radical generation in sepsis produces specific biochemical, structural and genetic changes that result in marked physiologic alterations in mitochondrial function. We postulate: (a) mitochondria dysfunction in sepsis results from physiologic derangements of Krebs cycle enzymes, Complex I-IV electron transport chain components, and sarcomericcreatine kinase, (b) these physiologic changes are due, in turn, to alterations in the content and composition of mitochondrial proteins, and (c) protein changes are due, in part, to free radical-mediated decrements in mitochondrial gene transcription, expression, and translation. These hypotheses will be tested in three groups of experiments, using a model of endotoxin-induced sepsis. The purpose of Objective 1 is to fully characterize the specific physiologic derangements in the mitochondria in sepsis; we will examine Krebs cycle enzyme activities, evaluate specific performance of complexes within the electron transport chain, assess sarcomeric mitochondrial creatine kinase activity, and perform a metabolic control analysis. Objective II will identify changes in the content and composition of mitochondrial protein constituents (i.e. electron transport chain protein subunits, Krebs cycle enzymes, creatine kinase) and compare the time course of these alterations with the development of physiologic abnormalities determined in Objective I. Objective III will evaluate transcription, expression, and translation of mitochondria and nuclear genes encoding for mitochondrial proteins found to be depleted in Objective II. In all studies, we will determine the role of free radical modulation of these sepsis-induced changes. Our preliminary data provide the first evidence of substantial sepsis-associated oxidative modification and depletion of mitochondria protein subunits in Complexes I, III and IV, significant alterations in NADH generation via Krebs cycle enzymes, major decreases in mitochondria creatine kinase activity, and key free radical-mediated changes in gene expression of mitochondrial proteins in sepsis. These data suggest that the proposed experiments should provide important information regarding the pathogenesis of mitochondrial dysfunction in sepsis.

描述（申请人的摘要）：最近的工作表明线粒体 功能障碍在败血症中起着核心作用，这是主要的死亡原因和 美国发病率。为此负责的基本机制 线粒体功能障碍尚不清楚。本提议的目的是 测试假设增加败血症的自由基产生的假设 特定的生化，结构和遗传变化，导致明显 线粒体功能的生理改变。我们假设：（a） 败血症的线粒体功能障碍是由生理危险引起的 克雷布斯循环酶，复杂的I-IV电子传输链成分和 肉瘤促性激酶，（b）这些生理变化反过来归功于 线粒体蛋白的含量和组成的改变，以及（c） 蛋白质的变化部分归因于自由基介导的减少 线粒体基因转录，表达和翻译。这些假设 将使用三组实验进行测试，使用 内毒素诱导的败血症。目标1的目的是完全表征 败血症线粒体中的特定生理危险；我们将 检查克雷布斯循环酶活性，评估特定性能 电子传输链中的复合物，评估肌膜线粒体 肌酸激酶活性，并执行代谢控制分析。客观的 II将确定线粒体内容和组成的变化 蛋白质成分（即电子传输链蛋白亚基，克雷布斯 循环酶，肌酸激酶）并比较这些时间过程 随着生理异常的发展的改变 目标I.目标III将评估转录，表达和 线粒体的线粒体和核基因的翻译 发现蛋白质已在目标II中耗尽。在所有研究中，我们都会 确定这些败血症诱导的变化的自由基调制的作用。 我们的初步数据提供了大量证据 败血症相关的氧化修饰和线粒体蛋白的耗竭 复合物I，III和IV中的亚基，NADH生成的重大变化 通过克雷布斯循环酶，线粒体肌酸激酶的主要减少 活性以及关键的自由基介导的基因表达变化 败血症中的线粒体蛋白。这些数据表明提议 实验应提供有关有关发病机理的重要信息 败血症中的线粒体功能障碍。