Chaperone-mediated Autophagy and Synaptic Dysfunction in Parkinson's Disease

帕金森病中分子伴侣介导的自噬和突触功能障碍

基本信息

批准号：
10248292
负责人：
ZIXU MAO
金额：
$ 49.29万
依托单位：
EMORY UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2018
资助国家：
美国
起止时间：
2018-08-01 至 2023-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10248292
关键词：
Aging Animal Disease Models Animal Model Autophagocytosis Autopsy Biochemical Biological Biological Models Brain Catabolic Process Cell Line Cell model Cell physiology Cells Cellular Stress Complex Data Defect Disease Event Functional disorder Genetic Homeostasis Human Hydrogen Peroxide Impairment Investigation LRRK2 gene Life Cycle Stages Link Literature Lysosomes Mediating Modeling Molecular Chaperones Neurodegenerative Disorders Neurons Oxidative Stress Oxides Parkinson Disease Pathogenesis Pathogenicity Pathway interactions Patients Physiological Play Pluripotent Stem Cells Prevention strategy Process Proteins Proton Pump Reagent Regulation Regulatory Pathway Reporting Rodent Rodent Model Role Signal Transduction Somatic Cell Stress Substantia nigra structure Synapses Synaptic Membranes Synaptic Vesicles Testing alpha synuclein base diagnostic biomarker disease phenotype disorder prevention dopaminergic neuron endoplasmic reticulum stress in vivo induced pluripotent stem cell innovation mutant neurotoxic neurotransmitter release new therapeutic target novel pars compacta prevent protein degradation proteostasis response stem cell model synaptic failure synaptic function targeted biomarker treatment strategy vacuolar H+-ATPase

项目摘要

Parkinson's disease (PD) is the second most common neurodegenerative disease characterized by the degenerative loss of dopaminergic (DA) neurons in the substantia nigra pars compacta. Studies of cellular and animal models and postmortem PD patient brains reveal that synaptic dysfunction triggered by environmental and genetic stress is an early event in PD pathogenesis. However, the precise and key mechanisms that underlie synaptic dysfunction in PD remain to be defined. The vacuolar (H+)-ATPase (V-ATPase) is an ATP- dependent proton pump involved in acidifying synaptic vesicles and plays a critical role in multiple steps of synaptic vesicle life cycle such as fusion with pre-synaptic membrane and neurotransmitter release/reloading. Our preliminary studies show that synaptic V-ATPase may be controlled by chaperone-mediated autophagy (CMA), a lysosome-based process specialized in disposing oxidized or damaged proteins for degradation to maintain cellular function under stress. Notably, CMA is inhibited by multiple stress conditions associated with PD including aging, neurotoxic stress, oxidative stress, ER stress, and genetic stress. However, whether and how cellular stress signals and CMA engage V-ATPase to modulate synaptic function is still unknown. In the current project, by utilizing multiple model systems, including cutting-edge human induced pluripotent stem cell (iPSC) model, in vivo rodent models (ER and genetic stress of rodent brains), and postmortem PD patient brains, we aim to determine whether CMA directly degrades damaged components of synaptic V-ATPase to maintain synaptic vesicle function under stress, and whether loss of adequate CMA activity impairs synaptic function in PD. First, we will determine biochemically, cell biologically, and electro-physiologically if CMA directly regulates synaptic V-ATPase and synaptic function in DA neurons derived from human iPSCs. Second, we will test if multiple stress conditions related to PD regulate synaptic V-ATPase and function via CMA in human iPSC-derived DA neurons. Last, we will assess the regulation and role of CMA–V-ATPase–synaptic vesicle pathway in multiple PD animal models and in postmortem brains from PD patients. Our proposed study will significantly advance our understanding of how stress regulates synaptic vesicle, reveal a key pathogenic mechanism underlying synaptic failure in PD, and offer new opportunities for developing diagnostics/biomarkers and more effective prevention and treatment strategies for the disease.

帕金森氏病（PD）是第二个最常见的神经退行性疾病，其特征是黑质Pars commacta中多巴胺能（DA）神经元的退化丧失。细胞和细胞的研究动物模型和事后PD患者大脑表明，环境触发的突触功能障碍遗传应激是PD发病机理的早期事件。但是，精确和关键机制 PD中的突触功能障碍的基础仍有待定义。液泡（H+） - ATPase（V-ATPase）是ATP- 与酸化突触蔬菜有关的依赖性质子泵，并在多个步骤中起着至关重要的作用突触囊泡生命周期，例如与突触前膜和神经递质释放/重新加载的融合。我们的初步研究表明，突触V-ATPase可以由伴侣介导的自噬控制（CMA），一种基于溶酶体的过程，专门处理氧化或受损的蛋白质以降解为在压力下保持细胞功能。值得注意的是，CMA受到与 PD包括衰老，神经毒性应激，氧化应激，ER应激和遗传应激。但是，是否和细胞应力信号和CMA如何使V-ATPase调节突触功能仍然未知。在当前项目，使用多个模型系统，包括尖端的人类诱导多能干细胞（IPSC）模型，体内啮齿动物模型（啮齿动物大脑的ER和遗传应力）和验尸PD患者大脑，我们旨在确定CMA是否将突触V-ATPase的受损部件降低到在压力下保持突触囊泡功能，以及是否丧失足够的CMA活性会损害突触 PD的功能。首先，如果CMA，我们将在生物化学，生物学上和电生物学上确定直接调节来自人IPSC的DA神经元中的突触V-ATPase和突触功能。第二，我们将测试与PD有关的多种应力条件是否调节突触V-ATPase和通过CMA在CMA中的功能人IPSC衍生的DA神经元。最后，我们将评估CMA – V-ATPase-突触的调节和作用多种PD动物模型和PD患者的后大脑中的囊泡途径。我们提出的研究将大大提高我们对压力如何调节突触囊泡的理解，揭示关键的致病性 PD突触失败的机制，为开发提供新的机会诊断/生物标志物以及对疾病的更有效的预防和治疗策略。