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 的检测方法极其灵敏、定量且可重复性高，并且可以检测任何类型的减缓聚合酶进展的损伤。当前申请所依据的母基金是实验性的，研究了暴露于线粒体毒素的大鼠中 mtDNA 损伤的各个方面。基本前提是线粒体毒素通过产生活性氧（ROS），会在线粒体中引起各种形式的DNA损伤。帕金森病 (PD) 在美国影响着约 100 万人，似乎涉及遗传和环境因素 - 并且与系统性线粒体缺陷密切相关。帕金森病最典型的环境风险因素是职业接触农药，其中许多是线粒体抑制剂。在这方面，当前的申请涉及两名流行病学家，他们在确定特定农药作为帕金森病的真正危险因素方面发挥了重要作用。新合作者 Caroline Tanner 和 Sam Goldman（加利福尼亚州桑尼维尔市帕金森病研究所）表明，使用鱼藤酮或百草枯这两种产生 ROS 的线粒体抑制剂的农民患 PD 的风险增加了一倍多。此外，他们报告称，接触溶剂三氯乙烯 (TCE) 也会增加帕金森病的风险。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 Tanner 和 Goldman 的流行病学研究中获得。因为 (i) PD 与线粒体缺陷和暴露于已知的线粒体毒素有关，并且 (ii) 即使大鼠亚临床暴露于线粒体毒素也会在血液中产生严重的 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 TCE 暴露是否会导致 mtDNA 损伤？人类接触鱼藤酮、百草枯或 TCE 是否与线粒体 DNA 损伤有关？无论是否接触鱼藤酮、百草枯或 TCE，散发性 PD 是否与线粒体 DNA 损伤有关？当前的提案建立在母申请的优势之上，具有创新且极其灵敏的 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 (Tanner & Goldman) 的桥梁。他们将利用现有技术和人员以及储存的 DNA 样本，努力开发一种生物标记物，用于检测人类接触某些环境毒物（例如鱼藤酮、百草枯和 TCE）的情况，并可能用于检测帕金森病。因此，与新研究相比，所提出的工作可以显着节省成本并提高效率。此外，主要研究人员有一个独特的机会在两个独立的流行病学队列中测试我们的检测作为 PD 生物标志物。鉴于他们的综合经验和专业知识，他们相信自己在评估这种潜在生物标志物方面具有独特的优势。