Role of Oxidative Stress and Protein Transporters in Glyphosate and Mancozeb Neur

描述（由申请人提供）：根据NIEHS的使命，了解环境如何影响人类疾病的病因和进展，本项目将研究两种高使用农药对一般神经毒性以及帕金森病（PD）的贡献。许多报告表明PD和农业环境和/或农药使用之间的联系。其他数据表明，接触锰（Mn）也可能与疾病发作有关。有趣的是，许多农用化学品以及Mn会损害线粒体呼吸，导致细胞存活所需的能量产生量不足。此外，线粒体功能障碍存在于PD患者的各种细胞群中。该项目的长期目标是了解农药可能导致与PD相关的脑区域细胞死亡的机制。利用秀丽隐杆线虫（Causophabditis elegans，C. elegans），将测试以下假设：暴露于流行的农药代森锰锌（MZ）和触地得分（TD）通过线粒体抑制和/或增加的氧化应激导致神经元变性。此外，推测这些农药可能通过特定的神经递质转运蛋白的摄取进入脆弱的神经元。 这些假设将通过三个特定目的进行检验：（1）确定哪些线粒体复合物受到抑制;（2）发现暴露于MZ和/或TD后增加的特定活性氧（ROS）;（3）确定MZ和TD是否通过单个神经递质或金属转运蛋白进入神经元。为了监测神经退行性变，C。将具有用绿色荧光蛋白（GFP）标记的神经元群体的线虫暴露于不同浓度的MZ或TD。随后将用各种化学报告物处理，以确定线粒体功能是否受损。后续研究将涉及使用特定神经递质转运蛋白拮抗剂对蠕虫进行预处理，以确定是否评估后续暴露于MZ或TD后变性是否减少。这些新研究的结果将进一步加深我们对与农药暴露相关的神经毒性效应的理解。此外，这项工作将提供与含草甘膦除草剂的细胞内转运机制相关的证据（即，TD，RoundUP）或含锰杀真菌剂（即，MZ，maneb）。预计这些数据将进一步我们的理解，不仅一般农药的神经毒性，但也通过环境毒物可能有助于特发性PD的病因机制。 公共卫生相关性：这些研究特别及时，与公共卫生有关，因为帕金森病（PD）是美国第二大最常见的神经退行性疾病，与农药暴露之间存在联系。使用含草甘膦除草剂（即，RoundUp和TouchDown）在公众和农业界呈指数级增长，而代森锰锌，一种含锰杀菌剂，正在获得越来越多的市场份额。这些农药被怀疑是线粒体抑制剂，在PD患者的各种细胞群中通常记录了这一观察结果。

DESCRIPTION (provided by applicant): In accordance with the mission of the NIEHS, understanding how environment influences human disease etiology and progression, this project will examine the contribution of two high-usage pesticides to general neurotoxicity as well as Parkinson's disease (PD). Numerous reports suggest a link between PD and agricultural environments and/or pesticide usage. Other data indicate that exposure to manganese (Mn) also may be linked to disease onset. Interestingly, many agrochemicals, as well as Mn, impair mitochondrial respiration, resulting in an insufficient quantity of energy production required for cells survival. Furthermore, mitochondrial dysfunction is present in various cell populations in PD patients. The long-term goal of this project is to understand the mechanisms through which pesticides may contribute to cell death in brain regions associate with to PD. Using the nematode Caenorhabditis elegans (C. elegans), the following hypothesis will be tested: Exposure to the popular pesticides Mancozeb (MZ) and TouchDown (TD) leads to neuronal degeneration via mitochondrial inhibition and/or increased oxidative stress. Additionally, it is hypothesized that these pesticides may enter vulnerable neuron through uptake by specific neurotransmitter transporters. These hypotheses will be tested through three specific aims: (1) to establish which mitochondrial complexes are inhibited; (2) to discover the specific reactive oxygen species (ROS) increased following exposure to MZ and/or TD; and (3) to determine if MZ and TD enter neurons through individual neurotransmitter or metal transporters. In order to monitor neurodegeneration, C. elegans with neuronal populations tagged with green fluorescent protein (GFP) will be exposed to varying concentrations of MZ or TD. This will be followed by treatment with various chemical reporters to determine whether mitochondrial function is compromised. Subsequent studies will involve pretreatment of worms with specific neurotransmitter transporter antagonists to determine if assess whether degeneration is decreased following subsequent exposure to MZ or TD. Results from these novel studies will further our understanding of neurotoxic effects related to pesticide exposure. Additionally, this work will provide evidence related to mechanisms involved in intracellular transport of glyphosate-containing herbicides (i.e., TD, RoundUP), or manganese-containing fungicides (i.e., MZ, maneb). It is anticipated that these data will further our understanding not only of general pesticide neurotoxicity, but also of mechanisms through which environmental toxicants may contribute the etiology of idiopathic PD. PUBLIC HEALTH RELEVANCE: These studies are particularly timely and relevant to public health because of the link between Parkinson's disease (PD), the second most-common neurodegenerative disease in the United States, and pesticide exposure. Use of glyphosate-containing herbicides (i.e., RoundUp and TouchDown) is increasing exponentially in the general public and the agricultural community, while Mancozeb, a manganese-containing fungicide, is gaining increased market shares. These pesticides are suspected mitochondrial inhibitors, an observation commonly documented in various cell populations in PD patients.