Mitochondrial Effects on Sensitivity to Anesthetics

线粒体对麻醉药敏感性的影响

• 批准号: 7145383
• 负责人: Margaret Mary Sedensky
• 金额: $ 40.03万
• 依托单位: CASE WESTERN RESERVE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-01-01 至 2010-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7145383
• 关键词: Caenorhabditis elegans; RNA interference; alternatives to animals in research; anesthetics; drug hypersensitivity; drug metabolism; electron transport; enzyme complex; enzyme mechanism; free radical oxygen; gene mutation; halothane; inhalation anesthesia; microarray technology; mitochondria; neurophysiology; oxidative phosphorylation; pharmacogenetics; pharmacokinetics

DESCRIPTION (provided by applicant): Our laboratory exploits a very simple animal model, the nematode C. elegans, to investigate the molecular mechanism of volatile anesthetic action. We have established that genes and physiologic pathways that alter anesthetic sensitivity in the nematode also alter sensitivity in mammals. The importance of the fact that the same molecular pathways affect sensitivity across different species is hard to overstate. We have identified a group of genes that alter mitochondrial function and control the sensitivity of C. elegans to volatile anesthetics (VAs). A point mutation in gas-1, which encodes the 49 kDa subunit of complex I of the mitochondrial electron transport chain, causes the animal to be very hypersensitive to all VAs. In addition, we have found that a subset of patients, children with metabolic defects most clearly related to complex I function, are profoundly hypersensitive to sevoflurane. This finding provides a clinical correlate to the basic study of very simple animal model. The sum of our work clearly implicates mitochondrial function as a novel mechanism that contributes to the control of anesthetic response. In this proposal we will extend our studies in the nematode to test our hypothesis that alterations in complex I function change anesthetic sensitivity via direct effects on metabolism, and via indirect effects on specific downstream proteins. The specific aims to test these hypotheses are: 1. Using an RNAi screen, determine which subunits of complex I alter anesthetic sensitivity in C. elegans. Our data indicate that the function of this complex is key to mediating behavior in VAs in nematodes, and may have a parallel role in patients with mitochondrial disease. 2. Using gene array analysis, we will determine genes and gene sets whose expression changes as a downstream effect of complex I dysfunction. We will restrict our analysis to expression profiles that alter anesthetic sensitivity by a subtraction strategy that focuses on changes specific to neurons. The microarray analysis will be validated by using RNAi to specifically reduce levels of expression of genes discovered in this aim, and test the resultant effects on behavior in VAs. This superb animal model allows putative molecular targets of VAs to be confirmed or refuted by assessing whole animal behavior. A tractable animal model is crucial to unraveling the mechanism of action of this very important class of anesthetic agents.

描述（由申请人提供）：我们的实验室利用一种非常简单的动物模型，线虫C。elegans，研究挥发性麻醉剂作用的分子机制。我们已经确定，基因和生理途径，改变麻醉敏感性的线虫也改变敏感性的哺乳动物。相同的分子途径影响不同物种的敏感性，这一事实的重要性怎么强调都不过分。我们已经确定了一组改变线粒体功能和控制C。挥发性麻醉剂（VAs）。编码线粒体电子传递链复合物I的49 kDa亚基的GAS-1中的点突变导致动物对所有VA非常过敏。此外，我们还发现，一部分患者（患有与复合物I功能最明显相关的代谢缺陷的儿童）对七氟烷高度过敏。这一发现为非常简单的动物模型的基础研究提供了临床相关性。我们的工作的总和清楚地暗示线粒体功能作为一种新的机制，有助于控制麻醉反应。在这项建议中，我们将扩展我们的研究，线虫来测试我们的假设，即改变复杂的I功能改变麻醉剂的敏感性，通过直接影响代谢，并通过对特定的下游蛋白质的间接影响。检验这些假设的具体目的是：1.使用RNAi筛选，确定复合物I的哪些亚基改变了C.优美的我们的数据表明，该复合物的功能是介导线虫VA行为的关键，并且可能在线粒体疾病患者中具有平行作用。2.使用基因阵列分析，我们将确定基因和基因集，其表达变化作为复合物I功能障碍的下游效应。我们将限制我们的分析表达谱，改变麻醉敏感性的减法策略，专注于特定的神经元的变化。微阵列分析将通过使用RNAi来特异性地降低在此目的中发现的基因的表达水平来验证，并测试对VA行为的结果影响。这种极好的动物模型允许通过评估整个动物行为来证实或反驳VA的假定分子靶点。一个易于处理的动物模型是至关重要的解开这类非常重要的麻醉剂的作用机制。