Super-Resolution In Vivo Optical Imaging as a Window to Parkinson's Disease Pathogenesis

帕金森氏症是一种使人衰弱的神经退行性疾病，全世界有500万人患有此病，仅在美国每年就花费140亿美元。大多数病例的病因尚不清楚，但遗传和环境因素与风险增加有关。该项目将揭示与帕金森病神经病理和进展相关的分子事件，从而促进新的治疗干预和更准确的预后。更广泛地说，将开发一种工具，用于识别与蛋白质折叠相关的其他中枢神经系统疾病的分子基础，如阿尔茨海默病和肌萎缩侧索硬化症，并用于评估这些疾病的新治疗方法。本科生将与研究生一起参与这个项目的各个方面。这项研究将用于普渡大学女性工程项目和普渡大学春节期间的大脑碗的演示，这两个项目都以K-12为目标。与此项目相关的实验室将在课堂上向学生开放，由研究人员讲授，以说明概念并展示课堂材料与研究的相关性，这是鼓励研究生研究和教育的令人兴奋的工具。一种新的基于荧光的光学分子成像方法将被开发和应用，作为一种手段，首次阐明与帕金森病神经病理时空发展相关的致病机制。突触前蛋白α -突触核蛋白的异常蛋白聚集被认为是一个关键的早期致病事件，并且假设聚集首先发生在全身，然后发生在脑干，然后在后期发生在大脑的特定区域，此时神经元丢失或功能障碍导致主要的运动和非运动症状。聚集体通过这些不同的大脑区域的传播被认为与疯牛病和克雅氏综合征中涉及的朊病毒蛋白的传播相似。了解α -突触核蛋白聚集与帕金森病之间的关系对于开发检测和治疗方案具有重要意义。异常的钙信号也是帕金森病的一个关键指标，钙离子在脆弱神经元中的扰动可以通过荧光报告来监测。提出的超分辨率光学成像方法将有能力确定α -突触核蛋白聚集和位点进展以及活动物大脑中的钙信号，可能达到10微米的分辨率。研究计划有两个目标。在FIRST Aim下，将进行同时的计算成像和大鼠模型研究，以研究被认为导致帕金森病进展的α -突触核蛋白朊病毒样扩散机制。每周收集的数据将逐步用于帮助确定α -突触核蛋白聚集的精确点位置。根据聚集水平的不同，这些位点的荧光寿命分布预计也会有所不同。在第二个目标下，时间信号信息将从细胞培养中荧光钙报告的显微镜测量中获得，并用于模拟大脑中的神经元激活。这项联合实验和建模工作将建立一个框架，以允许研究钙信号的干扰是否导致帕金森病的神经元功能障碍或丧失，以及钙和α -突触核蛋白之间的相互作用是否涉及神经毒性的假设。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Parkinson's disease is a debilitating neurodegenerative disorder afflicting 5 million people worldwide, costing $14 billion a year in the United States alone. The causes of most cases are unknown, but genetic and environmental factors are linked to increased risk. This project will reveal the molecular events related to Parkinson's disease neuropathology and progression, thus facilitating new therapeutic interventions and more accurate prognoses. More generally, a tool will be developed for identifying the molecular basis of other central nervous system disorders related to protein folding, such as Alzheimer's disease and amyotrophic lateral sclerosis, and for evaluating new treatment methods for these diseases. Undergraduate students will be incorporated into aspects of this project with graduate students. The research will be used to enhance demonstrations for the Purdue Women in Engineering program and at the Brain Bowl during Purdue's Spring Fest, both of which target K-12. The laboratories involved on this project will be opened to students in classes that the investigators teach to illustrate concepts and demonstrate the relevance of class material to research, an exciting tool for encouraging graduate research and education.A new fluorescence-based optical molecular imaging method suitable for the living brain will be developed and applied as a means to elucidate, for the first time, pathogenic mechanisms relating to the temporal and spatial development of Parkinson's disease neuropathology. Abnormal protein aggregation of the presynaptic protein alpha-synuclein is thought to be a critical early pathogenic event, and aggregation is postulated to occur first systemically, then in the brain stem, and then in later stages in specific areas of the brain where neuronal loss or dysfunction results in the cardinal motor and non-motor symptoms. The spread of aggregates through these different brain regions is thought to be similar to the spread of the prion protein involved in mad cow disease and Creutzfeldt-Jakob syndrome. Understanding the relationship between alpha-synuclein aggregation and Parkinson's disease is of fundamental importance, in order to develop detection and treatment options. Aberrant calcium signaling is also a key Parkinson's disease indicator, and calcium ion perturbations in vulnerable neurons can be monitored with available fluorescent reporters. The proposed super-resolution optical imaging method will have the capacity to determine alpha-synuclein aggregation and site progression as well as calcium signaling in the brain of a living animal, potentially with a resolution of ten microns. The Research Plan is organized under two aims. Under the FIRST Aim, a simultaneous computational imaging and rat model study will be pursued to investigate the alpha-synuclein prion-like spreading mechanism that is thought to result in Parkinson's disease progression. Data collected weekly will be progressively used to aid the determination of precise point locations for alpha-synuclein aggregation. The fluorescent lifetime distribution of these sites is also expected to differ, based on aggregation level. Under the SECOND Aim, temporal signaling information will be obtained from microscope measurements of fluorescent calcium reporters in cell cultures and used to simulate neuron activation in the brain. This joint experimental and modeling effort will build a framework to allow investigation of whether perturbations of calcium signaling underlie neuron dysfunction or loss in Parkinson's disease, and the hypothesis that interactions between calcium and alpha-synuclein are involved in neurotoxicity.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.