MtDNA damage as a biomarker for environmental mitochondrial toxicity

线粒体 DNA 损伤作为环境线粒体毒性的生物标志物

• 批准号: 8623989
• 负责人: J Timothy Greenamyre
• 金额: $ 44.62万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-19 至 2016-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8623989
• 关键词: Accounting; Address; Affect; Age; Agriculture; Behavioral; Biochemical; Biological; Biological Assay; Biological Markers; Blood; Blood specimen; Bolus Infusion; Case-Control Studies; Chemicals; Chronic; Complex; Cost Savings; DNA; DNA Damage; DNA Library; DNA lesion; Defect; Dose; Environmental Risk Factor; Epidemiologic Studies; Epidemiologist; Epidemiology; Etiology; Exposure to; Funding; Gender; Genetic; Genomic DNA; Health; Herbicides; Human; Injection of therapeutic agent; Institutes; Laboratories; Lead; Mitochondria; Mitochondrial DNA; Modeling; Mus; Nerve Degeneration; Nested Case-Control Study; Occupational; Occupational Exposure; Oxidation-Reduction; Oxidative Stress; Paraquat; Parents; Parkinson Disease; Participant; Pesticides; Polymerase; Positioning Attribute; Principal Investigator; Rattus; Reaction Time; Reactive Oxygen Species; Reporting; Research Design; Risk; Risk Factors; Rodent; Rotenone; Sampling; Smoking; Solvents; Specimen; Spouses; Subgroup; Technology; Testing; Tetrachloroethylene; Toxic Environmental Substances; Toxic effect; Toxin; Translational Research; Trichloroethylene; United States; Universities; Work; base; cohort; dopamine system; experience; exposed human population; farmer; gene environment interaction; human disease; illness length; inhibitor/antagonist; innovation; novel; parent grant; pesticide exposure; public health relevance

DESCRIPTION (provided by applicant): The Greenamyre laboratory (University of Pittsburgh) was recently funded to examine mitochondrial DNA (mtDNA) damage as a potential biomarker of exposure to environmental mitochondrial toxins. The PCR-based assay employed is extremely sensitive, quantitative and highly reproducible - and it detects any type of damage that slows polymerase progression. The parent grant, upon which the current application is based, is experimental and examines various aspects of mtDNA damage in rats exposed to mitochondrial toxins. The basic premise is that mitochondrial toxins, by generating reactive oxygen species (ROS), will cause various forms of DNA lesions in the mitochondria. Parkinson's disease (PD), affecting about 1 million people in the United States, appears to involve both genetic and environmental factors - and systemic mitochondrial defects have been strongly implicated. The best characterized environmental risk factor for PD is occupational exposure to pesticides, many of which are mitochondrial inhibitors. In this regard, the current application engages two of the epidemiologists who were instrumental in identifying specific pesticides as bona fide risk factors for PD. The new collaborators, Caroline Tanner and Sam Goldman (Parkinson's Institute, Sunnyvale, CA), showed that the risk of PD more than doubled in farmers using rotenone or paraquat, which are both ROS-generating mitochondrial inhibitors. Additionally, they reported that exposure to the solvent, trichloroethylene (TCE), also increases the risk of PD. In rats, TCE exposure is associated with inhibition of mitochondrial complex I. Importantly, existing genomic DNA samples are available from the epidemiological studies of Tanner and Goldman. Because (i) PD is associated with mitochondrial defects and exposures to known mitochondrial toxins, and (ii) even subclinical exposure of rats to a mitochondrial toxin produces robust mtDNA damage in blood, they propose specific aims to address the following questions: Does paraquat and/or TCE exposure cause mtDNA damage? Is human exposure to rotenone, paraquat or TCE associated with mtDNA damage? Is sporadic PD, with or without exposure to rotenone, paraquat or TCE associated with mtDNA damage? The current proposal builds upon the strengths of the parent application, with its innovative and extremely sensitive assay for mtDNA damage, and establishes a bridge from experimental work in rodents (Greenamyre) to translational research in the human epidemiology of Parkinson's disease (Tanner & Goldman). Using existing technology and staff, and banked DNA specimens, they will leverage current assets in an effort to develop a biomarker for human exposures to certain environmental toxicants (e.g., rotenone, paraquat & TCE) and, possibly, for Parkinson's disease. As a result, the proposed work can be done with dramatic cost savings and efficiency compared to a new study. Moreover, the principal investigators have a unique opportunity to test our assay as a biomarker for PD in two independent epidemiological cohorts. Given their combined experience and expertise, they believe they are uniquely positioned to assess this potential biomarker.

描述（由申请人提供）：Greenamyre实验室（匹兹堡大学）最近获得资助，以检查线粒体DNA（mtDNA）损伤作为暴露于环境线粒体毒素的潜在生物标志物。所采用的基于PCR的检测方法非常敏感，定量和高度可重复-它可以检测任何类型的减缓聚合酶进展的损伤。目前申请所依据的父母补助金是实验性的，并检查了暴露于线粒体毒素的大鼠线粒体DNA损伤的各个方面。其基本前提是线粒体毒素通过产生活性氧（ROS），会引起线粒体中各种形式的DNA损伤。帕金森病（PD）影响着美国约100万人，似乎涉及遗传和环境因素，而系统性线粒体缺陷也与此密切相关。PD最具特征的环境风险因素是职业性农药暴露，其中许多是线粒体抑制剂。在这方面，目前的申请涉及两名流行病学家，他们在确定特定农药为PD的真正风险因素方面发挥了重要作用。新的合作者Caroline坦纳和Sam Goldman（帕金森研究所，桑尼维尔，加利福尼亚州）表明，使用鱼藤酮或百草枯的农民患PD的风险增加了一倍多，这两种药物都是ROS产生的线粒体抑制剂。此外，他们报告说，接触溶剂三氯乙烯（TCE）也会增加患PD的风险。在大鼠中，TCE暴露与线粒体复合物I的抑制有关。 重要的是，现有的基因组DNA样本可从坦纳和戈德曼的流行病学研究中获得。由于（i）PD与线粒体缺陷和暴露于已知的线粒体毒素有关，（ii）即使大鼠亚临床暴露于线粒体毒素也会导致血液中的mtDNA损伤，因此他们提出了解决以下问题的具体目标：百草枯和/或三氯乙烯暴露是否会导致mtDNA损伤？人类接触鱼藤酮、百草枯或三氯乙烯是否与线粒体DNA损伤有关？散发性帕金森病是否与接触鱼藤酮、百草枯或三氯乙烯有关？目前的提案建立在母公司申请的优势之上，其创新和极其敏感的mtDNA损伤检测方法，并建立了从啮齿动物实验工作（Greenamyre）到帕金森病人类流行病学转化研究（坦纳& Goldman）的桥梁。利用现有的技术和人员，以及库存的DNA标本，他们将利用现有资产，努力开发人类暴露于某些环境毒物的生物标志物（例如，鱼藤酮，百草枯和三氯乙烯），并可能，帕金森氏病。因此，与新研究相比，拟议的工作可以节省大量成本和效率。此外，主要研究者有独特的机会在两个独立的流行病学队列中测试我们的测定作为PD的生物标志物。鉴于他们的综合经验和专业知识，他们相信他们在评估这种潜在的生物标志物方面具有独特的优势。