Toxicant evaluation in mice with selective dopamine transporter overexpression

选择性多巴胺转运蛋白过度表达小鼠的毒性评估

基本信息

批准号：
7513509
负责人：
Ali Salahpour
金额：
$ 5.44万
依托单位：
DUKE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2008
资助国家：
美国
起止时间：
2008-09-01 至 2009-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7513509
关键词：
1-Methyl-4-phenylpyridinium Address Affect Aftercare Animals Back Bradykinesia Cell Death Cell membrane Cells Chronic Data Disease Dopamine Etiology Evaluation Extracellular Space Gene Transfer Techniques Genes Genetic Homeostasis Individual Injury Lead Maintenance Mediating Midbrain structure Modeling Mouse Strains Mus Muscle Rigidity Mutant Strains Mice Nerve Nerve Degeneration Neuronal Injury Neurons Numbers Oxidative Stress Paraquat Parkinson Disease Parkinsonian Disorders Pathogenesis Phenotype Physiological Predisposition Protein Overexpression Proteins Quinones Reactive Oxygen Species Research Personnel Rest Tremor Role Rotenone Substantia nigra structure Synapses Technology Testing Tissues Title Toxic Environmental Substances Toxic effect Transgenic Animals Transgenic Mice Transgenic Organisms benzoquinone density dopamine transporter dopaminergic neuron extracellular gene environment interaction improved nervous system disorder neuron loss neurotoxic novel oxidation pars compacta postnatal programs reuptake toxicant uptake vector

项目摘要

DESCRIPTION (provided by applicant) Parkinson's disease (PD) is a chronic, progressive neurological disorder characterized by resting tremor, bradykinesia, postural instability and rigidity, resulting from the loss of dopamine (DA) neurons in the substantia nigra pars compacta (SNpc). The most vulnerable neurons affected in Parkinson's disease (PD) have the highest density of the phenotypic marker of DA neurons, the plasma membrane dopamine transporter (DAT). DAT is the major controller of DA neuron homeostasis being critically important not only for clearance of released DA from extracellular space but also for maintenance of intracellular DA stores. Thus by altering expression levels of the DAT it is possible to significantly change both extracellular and intracellular DA levels. The investigators recently developed a novel strain of mice over-expressing 6 copies of the DAT gene (DAT-Tg) specifically in the DA neurons by using BAG vector technology. Their preliminary results show that there is a 35% DA cell loss in the SN of these mice, most probably due to enhanced DA uptake and increased vulnerability of DA neurons to the neurotoxic effects of cytosolic endogenous DA. The investigators propose to use this strain of mutant mice to evaluate the effect of environmental toxicants known to induce DA cell loss and Parkinsonian phenotypes. There is ample evidence of gene/environment interaction resulting in increased susceptibility of individuals to the deleterious effects of toxicant. Here the investigators propose to directly evaluate whether increases in DAT level and intracellular DA may increase the toxicity induced by three model toxicants, namely MPTP, rotenone and paraquat. In parallel, they will also directly address whether augmenting DAT levels will lead to increased vulnerability of DA neurons to physiological concentrations of DA and of MPTP. For this, the investigators will use cultured postnatal SN neurons from transgenic mice with varied expression levels of DAT (DAT-KO, WT and DAT-tg). Using this approach it will be possible to test how DA induced toxicity correlates with DAT levels. This will hopefully allow them to address the specific importance of DAT in DA induced toxicity.

描述（由申请人提供）帕金森病 (PD) 是一种慢性进行性神经系统疾病，其特征为静止性震颤、运动迟缓、姿势不稳和僵硬，是由于黑质致密部 (SNpc) 中多巴胺 (DA) 神经元的缺失所致。帕金森病 (PD) 中最脆弱的神经元具有最高密度的 DA 神经元表型标记，即质膜多巴胺转运蛋白 (DAT)。 DAT 是 DA 神经元稳态的主要控制者，不仅对于清除细胞外空间释放的 DA 至关重要，而且对于维持细胞内 DA 储存也至关重要。因此，通过改变 DAT 的表达水平，可以显着改变细胞外和细胞内 DA 水平。研究人员最近利用 BAG 载体技术开发了一种新的小鼠品系，该小鼠品系特异地在 DA 神经元中过度表达 6 个拷贝的 DAT 基因 (DAT-Tg)。他们的初步结果表明，这些小鼠的 SN 中 DA 细胞丢失了 35%，很可能是由于 DA 摄取增强以及 DA 神经元对胞浆内源 DA 的神经毒性作用的脆弱性增加。研究人员提议使用这种突变小鼠品系来评估已知可诱导 DA 细胞丢失和帕金森表型的环境毒物的影响。有充分的证据表明基因/环境相互作用导致个体对毒物有害影响的敏感性增加。在这里，研究人员建议直接评估 DAT 水平和细胞内 DA 的增加是否会增加三种模型毒物（即 MPTP、鱼藤酮和百草枯）诱导的毒性。与此同时，他们还将直接解决增加 DAT 水平是否会导致 DA 神经元对 DA 和 MPTP 生理浓度的脆弱性增加。为此，研究人员将使用具有不同 DAT 表达水平（DAT-KO、WT 和 DAT-tg）的转基因小鼠培养的出生后 SN 神经元。使用这种方法将可以测试 DA 诱导的毒性与 DAT 水平的相关性。这有望使他们能够解决 DAT 在 DA 诱导毒性中的特殊重要性。