Aging-Related Models and Mitochondrial Bioenergetics

衰老相关模型和线粒体生物能学

• 批准号: 6640677
• 负责人: David Nicholls
• 金额: $ 36.86万
• 依托单位: BUCK INSTITUTE FOR RESEARCH ON AGING
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-03-01 至 2007-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6640677
• 关键词: action potentials; aging; bioenergetics; biological models; calcium ion; cellular respiration; cerebellum; free radical oxygen; functional /structural genomics; gene targeting; genetically modified animals; glutamates; hippocampus; laboratory mouse; membrane potentials; mitochondria; neurons; neurotoxins; oxidative stress; plant insecticide; proteomics; superoxide dismutase; tetany; tissue /cell culture

DESCRIPTION (provided by applicant): Oxidative stress and decreased mitochondrial respiratory chain capacity are both implicated in normal aging and may contribute to the increased incidence of neurodegenerative disease. It is possible that the slow insidious onset of neurodegenerative disease is because neuronal damage may advance in a quantal manner, each downward step being initiated by an acute energy deficit. The aim of this research proposal is to investigate the consequences of such bioenergetic compromise upon the ability of primary neuronal cultures from mouse hippocampus and cerebellum to withstand the patho-physiological stresses of acute glutamate excitotoxicity and tetanic action potential firing. In order to model enhanced oxidative stress, cells will be cultured from mice heterozygous for the Sod2 gene encoding mitochondrial Mn-superoxide dismutase. Chronic complex I restriction will be modelled by culturing cells from the wild-type mice in the presence of low concentrations of the respiratory chain inhibitor rotenone. The central bioenergetic parameter to be monitored will be the mitochondrial membrane potential, membrane potential while the key cellular functions controlled by membrane potential namely ATP synthesis, Ca2+ sequestration and the generation and detoxification of reactive oxygen species (ROS), will be monitored in parallel. Oxidative stress derived from Ca2+loaded mitochondria is implicated in the excitotoxic cell death induced by chronic NMDA receptor activation. Since ROS generation by isolated mitochondria is highly dependent upon membrane potential the hypothesis will be investigated that endogenous or synthetic means of controlling membrane potential can alleviate the deleterious consequences to the neurons of these bioenergetic stresses. The role of the novel candidate uncoupling protein UCP5 in controlling membrane potential will be assessed by in vitro over-expression, while the efficacy of synthetic protophores and lipophilic cations will be investigated. The hypothesis that this project will test that fine control of membrane potential by endogenous or artificial means may be a mechanism to counteract any increase, resulting from age related mitochondrial function, in the susceptabilty of neurons to excititoxic or epileptiform stress. Bioenergetic, proteomic and genomic information will be integrated in this study. The long-term goals of this project are 1. To facilitate the design of more precise mouse models of aging. 2. To establish the role of mitochondria in normal aging and aging-related neurodegenrative disorder. 3. To indicate therapeutic strategies whereby the deleterious consequences of aging-related changes in mitochondrial function can be minimized.

描述（由申请人提供）：氧化应激和减少 线粒体呼吸链能力都与正常衰老有关 并可能导致神经退行性疾病发病率增加。它 神经退行性疾病的缓慢隐匿发作可能是 因为神经元损伤可能以量子方式进展，每向下一步 由严重的能量不足引起。本研究计划的目的 是为了调查这种生物能量妥协对 小鼠海马和小脑的原代神经元培养物的能力 承受急性谷氨酸兴奋性毒性的病理生理应激 和强直性动作电位放电。为了模拟增强的氧化 应激时，将从 Sod2 基因杂合的小鼠中培养细胞 编码线粒体锰超氧化物歧化酶。慢性复合物 I 限制 将通过在存在以下物质的情况下培养野生型小鼠的细胞来建模 低浓度的呼吸链抑制剂鱼藤酮。中央 要监测的生物能参数是线粒体膜 电位，膜电位，而关键细胞功能由 膜电位，即 ATP 合成、Ca2+ 封存和生成 和活性氧（ROS）的解毒，将在 平行线。涉及来自 Ca2+ 负载线粒体的氧化应激 慢性 NMDA 受体激活诱导的兴奋性毒性细胞死亡。 由于分离的线粒体产生的 ROS 高度依赖于 膜电位假设将被研究内源性或 控制膜电位的合成方法可以减轻 这些生物能量应激对神经元产生有害后果。这 新型候选解偶联蛋白 UCP5 在控制膜中的作用 潜力将通过体外过度表达来评估，而功效 将研究合成原型载体和亲脂性阳离子。 假设该项目将测试膜的精细控制 通过内源或人工手段释放潜力可能是一种抵消机制 由于年龄相关的线粒体功能而导致的任何增加 神经元对兴奋性应激或癫痫样应激的敏感性。生物能量， 本研究将整合蛋白质组学和基因组学信息。长期来看 该项目的目标是 1. 促进更精确的设计 小鼠衰老模型。 2. 确定线粒体在正常细胞中的作用 衰老和与衰老相关的神经退行性疾病。 3. 表示治疗 策略，其中与衰老相关的变化的有害后果 线粒体功能可以最小化。