Mechanisms of Exercise-Induced Protection and Rescue in Models of Dopamine Loss

多巴胺丢失模型中运动诱导的保护和救援机制

• 批准号: 8526580
• 负责人: Barry J Hoffer
• 金额: $ 56.15万
• 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: 2011-09-30 至 2015-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8526580
• 关键词: Activities of Daily Living; Affect; Animal Model; Animals; Apoptosis; Astrocytes; Behavior; Behavioral; Blood Vessels; Brain; Brain-Derived Neurotrophic Factor; Bromodeoxyuridine; CD31 Antigens; Cells; Clinical; Clinical Research; Corpus striatum structure; Data; Development; Diffusion; Disease; Dopamine; Dopamine Receptor; Etiology; Event; Exercise; Extracellular Fluid; Family; Fluorescein-5-isothiocyanate; Functional disorder; Future; GDNF gene; Genes; Hippocampus (Brain); Immunohistochemistry; In Situ Hybridization; Individual; Intervention; Knock-out; Left; Legal patent; Measures; Microdialysis; Mitochondria; Modeling; Monitor; Motor; Motor Cortex; Nature; Neurons; Neurotoxins; PECAM1 gene; Parkinson Disease; Pharmacological Treatment; Prevention; Process; Proteins; Research; Respiration; Right-On; Role; Signal Transduction; Solid; Substantia nigra structure; Symptoms; Synapses; Testing; Therapeutic Intervention; Three-dimensional analysis; Tissues; Toxin; Vascular Endothelial Growth Factors; Western Blotting; angiogenesis; attenuation; base; density; design; disorder prevention; dopaminergic neuron; drug development; effective intervention; effective therapy; improved; insight; member; motor deficit; mouse model; multi-component intervention; neuron loss; neuroprotection; neurotrophic factor; novel; postsynaptic; preconditioning; programs; protective effect; receptor; receptor expression; response; tomato lectin; uptake

DESCRIPTION (provided by applicant): Parkinson's disease (PD) affects at least 1 million individuals in the US alone. Although much is known about its pathophysiology and information is emerging about its cause, there are no pharmacological treatments shown to have a significant, sustained impact on the prevention of PD or on attenuation of its progress. However, clinical evidence suggests that physical exercise is such a treatment, and this is supported by studies of animal models of the dopamine (DA) deficiency associated with the motor symptoms of PD. Moreover, exercise is a practical and sustainable therapeutic intervention likely to act simultaneously on most if not all of the cellular events capable of protecting DA neurons and restoring DA function. This proposal is designed test the hypothesis that exercise increases DA function and protects DA neurons against toxic insult due in part to increased neurotrophic factor (NTF) signaling, protection of mitochondrial respiration, and stimulation of angiogenesis. An MPTP mouse model will be used to test this hypothesis. Aim 1. To determine the effects of exercise on the impact of MPTP on dopaminergic function (1a) the optimal temporal relationship between exercise and toxin exposure will first be established, thus exploring both protection (exercise before toxin) and rescue (exercise after toxin). (1b) The impact of the optimal exercise paradigm on DA cell loss and on changes in pre- and post-synaptic DA receptors will then be assessed. (1c) Levels of DA and metabolites in striatal tissue and extracellular fluid will be measured in MPTP animals treated with exercise as dictated by Aim 1a. (1d) Mitochondrial respiration will be assessed after MPTP exercise. Aim 2. To assess the role of NTFs in exercise-induced protection members of four distinct NTF families known to protect DA neurons will be examined: GDNF, BDNF, MANF, and VEGF. (2a) The temporal and anatomical profile of NTF changes will be determined after exercise, MPTP, and the optimal combination of MPTP and exercise. (b) The ability of exogenous NTF to mimic the effects of exercise identified in Aim 1 will then be assessed. (2c) The NTFs and/or their receptors suggested by Aim 2a and 2b will be conditionally knocked out to determine if this increases the toxin impact of MPTP and reduces the protective impact of exercise, thereby strengthening the hypothesis of a causal relationship between NTF and exercise-induced protection. Aim 3. To examine the role of angiogenesis in exercise- and NTF-induced neuroprotection, (a) vasculature be assessed in substantia nigra, striatum, and cortex using BrdU to measure new cells and PECAM-1 (CD31), to mark blood vessels. (3b) FITC-conjugated tomato lectin will be used to detect patent blood vessels. (3c) A 3-dimensional analysis of vascular density will be performed. (3d) Finally, expression of angiogenesis-promoting proteins, including angiopoetins 1 and 2, will be measured. These results will provide the basis for the next iteration of a research program focusing on additional mechanisms underlying exercise-induced protection, provide stronger evidence for exercise-induced protection in PD, and establish targets for pharmacological treatment of the condition.

描述（由申请人提供）：帕金森病（PD）仅在美国就影响至少100万人。尽管对其病理生理学了解很多，并且关于其原因的信息正在出现，但没有药物治疗显示对预防PD或减缓其进展具有显著，持续的影响。然而，临床证据表明，体育锻炼是这样一种治疗方法，这是由与PD运动症状相关的多巴胺（DA）缺乏症的动物模型研究支持的。此外，运动是一种实用且可持续的治疗干预，可能同时作用于大多数（如果不是所有）能够保护DA神经元和恢复DA功能的细胞事件。该提议旨在检验运动增加DA功能并保护DA神经元免受毒性损伤的假设，这部分是由于增加神经营养因子（NTF）信号传导、保护线粒体呼吸和刺激血管生成。将使用MPTP小鼠模型来检验该假设。目标1。为了确定运动对MPTP对多巴胺能功能的影响（1a），首先将建立运动与毒素暴露之间的最佳时间关系，从而探索保护（毒素前运动）和拯救（毒素后运动）。(1b)然后将评估最佳运动模式对DA细胞损失和突触前和突触后DA受体变化的影响。(1c)根据目的1a的规定，将在接受运动治疗的MPTP动物中测量纹状体组织和细胞外液中的DA和代谢物水平。(1d)将在MPTP运动后评估线粒体呼吸。目标2.为了评估NTFs在运动诱导的保护中的作用，将检查已知保护DA神经元的四个不同NTFs家族的成员：GDNF、BDNF、MANF和VEGF。(2a)NTF变化的时间和解剖学特征将在运动、MPTP以及MPTP和运动的最佳组合后确定。(b)然后评估外源性NTF模拟目标1中确定的运动效果的能力。(2c)目标2a和2b所建议的NTF和/或其受体将被有条件地敲除，以确定这是否增加MPTP的毒素影响并降低运动的保护作用，从而加强NTF和运动诱导的保护之间的因果关系的假设。目标3。为了检查血管生成在运动和NTF诱导的神经保护中的作用，（a）使用BrdU测量新细胞和PECAM-1（CD 31）标记血管来评估黑质、纹状体和皮质中的脉管系统。(3b)FITC标记的番茄凝集素将用于检测未闭血管。(3c)将进行血管密度的三维分析。(3d)最后，将测量血管生成促进蛋白（包括血管生成素1和2）的表达。这些结果将为下一次迭代的研究计划提供基础，重点是运动诱导的保护的其他机制，为PD运动诱导的保护提供更有力的证据，并建立药物治疗的目标。