Mass Spectrometry And Oxidative Stress

质谱法和氧化应激

• 批准号: 6673017
• 负责人: Kenneth Tomer
• 金额: --
• 依托单位: NATIONAL INSTITUTE OF ENVIRONMENTAL HEALTH SCIENCES
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6673017
• 关键词: DNA damage; adduct; aging; cytochrome c; electron spin resonance spectroscopy; free radicals; glutathione; horses; hydrogen peroxide; inflammation; lipid peroxides; mass spectrometry; matrix assisted laser desorption ionization; mitochondria; nitroso compounds; oxidation reduction reaction; oxidative stress; peroxidation; phosphorylation; protein degradation

Summary of Work: The study of oxidative stress has attracted considerable interest and has been the focus of much research in recent years. Cumulative oxidative damage to tissues has been implicated in a number of disease states, e.g. the aging process, cancer, and ischemia reperfusion. The study of oxidative stress in the mitochondria has shown that hydrogen peroxide is produced via the incomplete reduction of oxygen during oxidative phosphorylation. Hydrogen peroxide levels are kept relatively low under normal physiological conditions. Under certain conditions, such as inflammation, excessive amounts of hydrogen peroxide are produced. The production of excess hydrogen peroxide is thought to precede several occurrences, such as lipid peroxidation, DNA and/or protein damage, and glutathione depletion, that are characteristic of oxidative stress. In a long-term collaboration with the epr group (Mason/LPC) we have been investigating the sites of radical formation on proteins and peptides and have been determining the specific site on the amino acid which undergoes radical formation during oxidation by determining the structure of the amino acid spin-trap covalent adduct. This information is important to our understanding of the damage that can occur by free-radical oxidation of proteins and how that damage occurs. The study of oxidative stress has attracted considerable interest and has been the focus of much research in recent years. Hydrogen peroxide levels are kept relatively low under normal physiological conditions. Under certain conditions, such as inflammation, excessive amounts of hydrogen peroxide are produced. The production of excess hydrogen peroxide is thought to precede several occurrences, such as lipid peroxidation, DNA and/or protein damage, and glutathione depletion, that are characteristic of oxidative stress. In a long-term collaboration with the epr group (Mason/LPC) we have been investigating the sites of radical formation on lipids and on proteins and peptides. For proteins and peptides we have been determining the specific site on the amino acid which undergoes radical formation during oxidation by determining the structure of the amino acid spin-trap covalent adduct. This information is important to our understanding of the damage that can occur by free-radical oxidation of proteins and how that damage occurs. Investigation of the mechanism of development of Parkinson's disease: In collaboration with R. Mason (LPC) and G. Pielak (UNC), we are involved in a project whose aims is to probe how a-synuclein undergoes Lewy body formation. The working hypothesis is that oxidative damage to heme proteins such as cyt c leads to release of the cyt c from the mitochondria. Upon release, the cyt c free radical can react further with other proteins, such as a-synuclein. These secondary free-radical proteins can then undergo either chemical cross-linking or conformational changes that lead to aggregation.

工作概述：近年来，氧化应激的研究引起了人们极大的兴趣，并成为许多研究的焦点。对组织的累积性氧化损伤与许多疾病状态有关，例如衰老过程、癌症和缺血再灌注。线粒体中氧化应激的研究表明，过氧化氢是通过氧化磷酸化过程中氧的不完全还原产生的。过氧化氢水平在正常生理条件下保持相对较低。在某些条件下，如炎症，会产生过量的过氧化氢。过量过氧化氢的产生被认为先于几种事件，如脂质过氧化、DNA和/或蛋白质损伤和谷胱甘肽耗竭，这些都是氧化应激的特征。在与epr小组（Mason/LPC）的长期合作中，我们一直在研究蛋白质和肽上自由基形成的位点，并通过确定氨基酸自旋捕获共价加合物的结构来确定在氧化过程中经历自由基形成的氨基酸上的特定位点。这些信息对于我们理解蛋白质自由基氧化可能造成的损害以及这种损害是如何发生的非常重要。 近年来，氧化应激的研究引起了人们极大的兴趣，并成为许多研究的焦点。过氧化氢水平在正常生理条件下保持相对较低。在某些条件下，如炎症，会产生过量的过氧化氢。过量过氧化氢的产生被认为先于几种事件，如脂质过氧化、DNA和/或蛋白质损伤和谷胱甘肽耗竭，这些都是氧化应激的特征。在与EPR小组（Mason/LPC）的长期合作中，我们一直在研究脂质、蛋白质和肽上自由基形成的位点。对于蛋白质和肽，我们已经确定了特定的网站上的氨基酸进行自由基形成在氧化过程中，通过确定的氨基酸自旋捕获共价加合物的结构。这些信息对于我们理解蛋白质自由基氧化可能造成的损害以及这种损害是如何发生的非常重要。 帕金森病发病机制的研究：与R。Mason（LPC）和G. Pielak（1999），我们参与了一个项目，其目的是探索α-突触核蛋白如何经历路易体形成。工作假设是血红素蛋白如cyt c的氧化损伤导致cyt c从线粒体中释放。释放后，细胞色素c自由基可以进一步与其他蛋白质反应，如α-突触核蛋白。然后，这些二级自由基蛋白质可以发生化学交联或构象变化，从而导致聚集。