Metals and Metal Mixtures: Cognitive Aging, Remediation and Exposure Sources (MEMCARE)

项目描述： 全球预期寿命的增加导致了无法治愈的神经退行性疾病的发生率更高。 尽管遗传倾向和年龄是已知的神经退行性疾病的危险因素，但它已经成为 越来越清楚--通过一种未知的机制，暴露于铅(铅)会增加这些认知障碍的风险 精神错乱。确定早期接触铅导致神经退行性变的分子机制 对于开发预防其发病的治疗方法是至关重要的。结构和功能的渐进性丧失 在神经元中，其特征是神经退行性疾病涉及到 神经元和小胶质细胞。以从根本上改变它们的形态和功能而闻名 在环境中，小胶质细胞对铅等毒素做出反应，导致邻近神经元应激和死亡。 使用基于分子和细胞生物学的方法，我目前在MEMCARE-SRC的超级基金研究 铅暴露如何影响诱导多能干细胞产生的信号分子 (IPSC)来源的小胶质细胞。这项工作描述了小胶质细胞释放的细胞外信号分子。 它们会增强神经毒性，并可能作为认知障碍的生物标志物。识别细胞内的 铅改变小胶质细胞释放的这些信号分子的机制将极大地有利于 MEMCARE的目标，旨在评估早年接触金属如何导致认知能力下降。 我建议利用克里斯·张博士的实验室中主持的K.C.Donnelly Externship来研究有毒物质 在加州大学伯克利分校的环境超级基金研究项目中调查铅是如何 暴露使用一种新的基于化学生物学的方法来修饰小胶质细胞信号分子。我们 假设铅暴露增加了IPSC来源的小胶质细胞培养中的细胞应力。我会的 接受培训以应用基于活动的传感(ABS)和标记分析来可视化和量化两个分子 铅暴露下IPSC来源的小胶质细胞的细胞应激标志物。IPSCs将分化为稳定的 我家里实验室的小胶质细胞前体随后使用一种既定的方案运往伯克利。前兆 小胶质细胞将发育为完全成熟的小胶质细胞，并随后暴露于铅。ABS和标签将 使用探针荧光标记细胞应激的两个标志物--过氧化氢和丙二醛 由张实验室开发。共聚焦显微镜和流式细胞术将检测和量化这些标志物， 分别进行了分析。该项目的完成将揭示铅诱导的细胞应激是否是 小胶质细胞信号分子释放，缩小旨在预防的治疗的分子靶点 小胶质细胞介导的神经毒性。此外，我将接受ABS使用方面的培训，并将这一创新 化学传感器具有强大的、相关的模型小胶质细胞的功能，使两家超级基金受益 中锋。

PROJECT DESCRIPTION: Increased global life expectancy has led to higher incidences of incurable neurodegenerative disorders. Although genetic predisposition and age are known risk factors for neurodegenerative disorders, it has become increasingly clear – via an unknown mechanism, exposure to lead (Pb) increases the risk of these cognitive disorders. Identifying the molecular mechanism by which early-life exposure to Pb results in neurodegeneration is essential for the development of therapies to prevent its onset. The progressive loss of structure and function in neurons which characterizes neurodegenerative disorders involves complex communication between neurons and microglia. Known for radically altering their morphology and function in response to their environmental, microglia respond to toxins, such as Pb, inducing stress and death in neighboring neurons. Using molecular and cell biology-based approaches, my current Superfund research at the MEMCARE-SRC characterizes how Pb exposure impacts signaling molecules generated by induced pluripotent stem cell (iPSC)-derived microglia. This work characterizes the extracellular signaling molecules released by microglia which potentiate neurotoxicity and may serve as biomarkers of cognitive disorders. Identifying the intracellular mechanism through which Pb alters these signaling molecules released by microglia would greatly benefit the goals of MEMCARE, which aims to evaluate how early-life exposure to metals contributes to cognitive decline. I propose to leverage a K.C. Donnelly Externship hosted in the lab of Dr. Chris Chang of the Toxic Substances in the Environment Superfund Research Program at University of California Berkeley to investigate how Pb exposure modifies microglia signaling molecules using a novel chemical-biology based approach. We hypothesize that Pb exposure increases cellular stress in iPSC-derived microglia culture. I will be trained to apply an activity-based sensing (ABS) and labeling assay to visualize and quantify two molecular markers of cellular stress in iPSC-derived microglia exposed to Pb. iPSCs will be differentiated into a stable microglia precursor in my home lab then shipped to Berkeley using an established protocol. Precursor microglia will be developed into fully matured microglia and subsequently exposed to Pb. ABS and labeling will fluorescently tag two markers of cellular stress, hydrogen peroxide and malondialdehyde, using probes developed by the Chang lab. Confocal microscopy and flow cytometry will detect and quantify these markers, respectively. Completion of this project will reveal if Pb induced cellular stress is the modifying mechanism of microglia signaling molecule release, narrowing down molecular targets for therapies aimed to prevent microglia-mediated neurotoxicity. Further, I will be trained in the use of ABS and will integrate this innovative chemical sensor with a powerful, relevant model of microglia cell function to the benefit of both Superfund centers.