Determining how neural activity impairs bioenergetics in PD pathogenesis

确定神经活动如何损害 PD 发病机制中的生物能学

• 批准号: 9257471
• 负责人: KEN NAKAMURA
• 金额: $ 42.27万
• 依托单位: J. DAVID GLADSTONE INSTITUTES
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-01 至 2020-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9257471
• 关键词: Affect; Age; Axon; Behavior; Bioenergetics; Biological Assay; Brain; Cell Respiration; Cells; Cessation of life; Chronic; Complex; Consumption; Corpus striatum structure; Data; Defect; Dependovirus; Dopamine; Doxycycline; Failure; Functional disorder; Genetic; Glycolysis; Goals; Impairment; In Vitro; Individual; Lead; Measures; Methods; Midbrain structure; Mitochondria; Mitochondrial Proteins; Mus; Mutation; Nerve Block; Nerve Degeneration; Neurons; PINK1 gene; PTEN-induced putative kinase; Parkinson Disease; Pathogenesis; Pharmacogenetics; Play; Presynaptic Terminals; Preventive treatment; Process; Production; Rattus; Research Personnel; Respiratory physiology; Role; Substantia nigra structure; Synapses; Synaptic Vesicles; Testing; Toxic effect; Translating; Work; base; cohort; design; designer receptors exclusively activated by designer drugs; dopaminergic neuron; in vivo; innovation; insight; killings; mitochondrial dysfunction; myelination; nervous system disorder; neuron loss; postnatal; public health relevance; relating to nervous system; stressor; therapeutic target; tool; vesicular release

 DESCRIPTION (provided by applicant): Parkinson's disease (PD) is a progressive neurological disorder in which dopamine (DA) neurons in the brain degenerate and die. A genetic form of PD is caused by mutations in the mitochondrial protein PINK1, which proves that DA neurons are selectively vulnerable to specific mitochondrial stressors. Interestingly, considerable evidence suggests that mitochondrial function is also disrupted in sporadic (rather than genetic) forms of PD, and these changes may also selectively kill DA neurons. So, why are DA neurons susceptible to mitochondrial dysfunction? Because a critical role of mitochondria is to produce energy, many researchers believe that DA neurons are susceptible to energy failure. For example, DA neurons may not be able to produce as much energy or they might require more energy than other types of neurons. Indeed, much of the brain's energy is dedicated to supporting neural activity, and the activity of DA neurons may increase in PD. However, although many believe that energy failure plays a central role in PD pathophysiology, we know remarkably little about energy levels in DA neurons; we don't know if energy failure even occurs in these cells. In order to investigate energy failure in DA neurons, we developed innovative assays to measure ATP and visualize mitochondria in individual neurons. With these methods, we can now test our central hypothesis that DA neurons intrinsically require more energy than other types of neurons to sustain their neural activity, making them particularly susceptible to insults that further increase their energy demands or compromise mitochondrial function. The overall objective of the proposed study is to understand if DA neurons have intrinsic differences in the way they produce or consume energy that make them susceptible to energy failure. We will accomplish these objectives in three specific aims. (1) We will determine if DA neurons have intrinsic deficits in mitochondrial bioenergetic function at the synapse. To do this, we will measure energy production and consumption in individual DA neurons with our newly developed assays to evaluate mitochondrial energy levels in individual synaptic boutons. (2) We will determine if and how loss of the PD protein PINK1 compromises bioenergetic function in DA neurons by determining how losing PINK1 affects these neurons' mitochondrial distribution and function. (3) We will determine if the level of neural activity makes DA neurons even more susceptible to energy failure by assessing their function and death after changing activity levels. Overall, these studies will advance our understanding of if and how energy failure develops in DA neurons, and they will provide insight into how we might therapeutically target energy failure in PD.

 描述(申请人提供)：帕金森病(PD)是一种进行性神经系统疾病，大脑中的多巴胺(DA)神经元退化和死亡。帕金森病的一种遗传形式是由线粒体蛋白PINK1的突变引起的，这证明DA神经元选择性地易受特定线粒体应激源的影响。有趣的是，相当多的证据表明，散发性(而不是遗传性)帕金森病的线粒体功能也被破坏，这些变化也可能选择性地杀死DA神经元。那么，为什么DA神经元容易受到线粒体功能障碍的影响？由于线粒体的关键作用是产生能量，许多研究人员认为DA神经元容易受到能量衰竭的影响。例如，DA神经元可能不能产生同样多的能量，或者它们可能比其他类型的神经元需要更多的能量。事实上，大脑的大部分能量都致力于支持神经活动，而帕金森病患者DA神经元的活动可能会增加。然而，尽管许多人认为能量衰竭在帕金森病的病理生理学中起着核心作用，但我们对DA神经元的能量水平知之甚少；我们甚至不知道这些细胞是否发生了能量衰竭。为了研究DA神经元中的能量衰竭，我们开发了创新的方法来测量ATP并可视化单个神经元中的线粒体。通过这些方法，我们现在可以检验我们的中心假设，即DA神经元固有地比其他类型的神经元需要更多的能量来维持其神经活动，使它们特别容易受到进一步增加其能量需求或损害线粒体功能的侮辱。这项拟议研究的总体目标是了解DA神经元在产生或消耗能量的方式上是否存在内在差异，从而使它们容易受到能量衰竭的影响。我们将通过三个具体目标实现这些目标。(1)我们将确定DA神经元在突触处是否存在线粒体生物能量功能的内在缺陷。为了做到这一点，我们将用我们新开发的方法来测量单个DA神经元的能量产生和消耗，以评估单个突触突触的线粒体能量水平。(2)我们将通过确定PINK1缺失如何影响DA神经元的线粒体分布和功能，来确定PD蛋白PINK1的缺失是否以及如何影响DA神经元的生物能量功能。(3)我们将通过评估DA神经元在改变活动水平后的功能和死亡来确定神经活动水平是否会使DA神经元更容易受到能量衰竭的影响。 总体而言，这些研究将促进我们对DA神经元是否以及如何发生能量衰竭的理解，并将为我们如何从治疗上针对帕金森病的能量衰竭提供洞察力。