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，这个项目将研究两种高使用量的杀虫剂对一般神经毒性和帕金森病(PD)的贡献。许多报告表明帕金森病与农业环境和/或农药使用之间存在联系。其他数据表明，接触锰(Mn)也可能与疾病的发病有关。有趣的是，许多农用化学品以及锰都会损害线粒体的呼吸，导致细胞生存所需的能量生产不足。此外，在PD患者的不同细胞群中也存在线粒体功能障碍。该项目的长期目标是了解杀虫剂可能通过哪些机制导致与帕金森病相关的脑区细胞死亡。利用线虫秀丽线虫(C.elegans)，将检验以下假设：暴露于流行的杀虫剂代森锰锌(MZ)和触杀(TD)会通过线粒体抑制和/或氧化应激增加导致神经元退化。此外，假设这些农药可能通过被特定的神经递质转运蛋白摄取而进入脆弱的神经元。这些假说将通过三个特定的目标来检验：(1)确定哪些线粒体复合体被抑制；(2)发现暴露于MZ和/或TD后特定的活性氧物种(ROS)增加；以及(3)确定MZ和TD是否通过单独的神经递质或金属转运体进入神经元。为了监测神经退化，带有绿色荧光蛋白(GFP)标记的神经元种群的线虫将暴露于不同浓度的MZ或TD。随后将使用各种化学记者进行治疗，以确定线粒体功能是否受到损害。随后的研究将涉及用特定的神经递质转运体拮抗剂对蠕虫进行预处理，以确定是否评估随后暴露于MZ或TD后变性是否减少。这些新的研究结果将进一步加深我们对与农药接触有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(即TD，农达)或含锰杀菌剂(即，MZ，maneb)细胞内转运机制有关的证据。预计这些数据不仅将加深我们对一般农药神经毒性的理解，还将加深我们对环境毒物可能导致特发性帕金森病病因的机制的理解。 公共卫生相关性：这些研究特别及时，与公共健康相关，因为帕金森氏病(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。在普通公众和农业社区中，含草甘膦除草剂(即农达和除草剂)的使用量呈指数级增长，而含锰杀菌剂代森锰锌的市场份额正在增加。这些杀虫剂被怀疑是线粒体抑制剂，这一观察结果通常记录在帕金森病患者的各种细胞群中。

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.