Astrocyte NLRP3 inflammasome activation in Parkinson's disease

帕金森病中星形胶质细胞 NLRP3 炎性体激活

• 批准号: 10192615
• 负责人: Jared Hinkle
• 金额: $ 5.1万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-05-01 至 2023-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10192615
• 关键词: Ablation; Adopted; Adult; Age; Astrocytes; Brain; CASP1 gene; Cause of Death; Cell Count; Cell Culture Techniques; Cell Death; Cells; Cleaved cell; Complement 1q; Complex; Computer Assisted; Confocal Microscopy; Data; Detergents; Development; Disease; Doctor of Philosophy; Dopamine; Elements; Ensure; Enterobacteria phage P1 Cre recombinase; Etiology; Event; Exhibits; Feasibility Studies; Fluorescence Microscopy; Gene Targeting; Goals; Immune; Immunologics; Inflammasome; Inflammation; Inflammatory; Injections; Innate Immune System; Institution; Interleukin-1 alpha; Interleukin-1 beta; Investigation; Knockout Mice; Link; Literature; Measures; Mentorship; Modeling; Mus; Natural Immunity; Nerve Degeneration; Neurodegenerative Disorders; Neuroglia; Neuroimmune; Neurologic; Neurons; Nigericin; Parkinson Disease; Pathogenesis; Pathogenicity; Pathologic; Pathology; Patient Care; Phenotype; Physicians; Prevalence; Process; Proteins; Research; Research Personnel; Role; Scientist; Specificity; Substantia nigra structure; TNF gene; Testing; Training; Transgenic Organisms; Translational Research; Universities; Vacuum; aging population; alpha synuclein; career development; cytokine; doctoral student; dopaminergic neuron; in vitro Model; insight; monomer; mouse model; neurotoxic; neurotoxicity; novel; protein aggregation; response; skills; success; synucleinopathy; therapeutic target; transcriptome

Project Summary Rapid population ageing portends dramatic increases in the prevalence of adult-onset neurodegenerative disorders such as Parkinson’s disease (PD) in the coming decades. Inflammation, long considered an age- associated epiphenomenon of neurodegeneration, has gradually been recast as a causal factor through newly described neuroimmune disease mechanisms. Astrocytes are the predominant type of glial cell in the brain and are induced by inflammatory cytokines to adopt a neurotoxic A1 reactive phenotype, which my PhD thesis lab has linked to the degeneration of dopamine neurons in PD. However, the mechanisms by which A1 astrocytes contribute to early events in PD pathogenesis, such as the pathologic aggregation of α-synuclein (αSyn), remain undefined. Understanding these processes will clarify the value of A1 astrocytes as a therapeutic target in early PD and may suggest novel roles in other neurodegenerative and neuroimmune disorders. My preliminary data show that A1 astrocytes exhibit robust induction of the NLRP3 inflammasome, an effector of the innate immune system recently implicated in αSyn aggregation. Furthermore, I have shown that primary astrocyte cell cultures (1) can canonically activate the NLRP3 inflammasome, (2) readily internalize αSyn, and (3) increase NLRP3 expression and IL-1β secretion in response to fibrillar αSyn aggregates, consistent with inflammasome activation. Therefore, the central hypothesis of this proposal is that astrocyte NLRP3 inflammasome assembly can drive pathogenic αSyn aggregation, which in turn reinforces NLRP3 activation and inflammation in PD. In Aim 1, we will determine whether the NLRP3 inflammasome promotes αSyn aggregation in A1 astrocytes. In Aim 2, we will investigate astrocyte NLRP3 inflammasome activation by exogenous αSyn fibrils. In Aim 3, we will demonstrate pathogenicity of astrocyte NLRP3 activation in the αSyn preformed fibril (PFF) mouse model of PD. Primary astrocyte cultures will be used to establish the mechanistic plausibility of this model in vitro. We will use transgenic and gene-targeted mice to selectively delete NLRP3 in astrocytes and examine the impact on PD pathology in the αSyn PFF mouse model. Our research will identify a novel mechanism by which A1 astrocytes contribute to early PD pathogenesis by promoting the aggregation of αSyn into toxic species (Aim 1) and further show how αSyn can activate the potent NLRP3 inflammatory cascade in astrocytes (Aim 2). We will also demonstrate that these processes have causal relevance in a well- characterized PD mouse model (Aim 3). Collectively, this project will enhance our understanding of astrocytes in PD etiology and characterize a novel disease role for the NLRP3 inflammasome. These studies comprise the scientific context of my training plan as an MD/PhD student at Johns Hopkins, which will facilitate my development as an independent physician-scientist. My sponsor, Ted Dawson, MD/PhD, is fully committed to supporting my success in this research and my long-term career-development.

项目概要 人口快速老龄化预示着成人发病的神经退行性疾病患病率急剧增加 未来几十年，帕金森病（PD）等疾病将得到缓解。炎症，长期以来被认为是一种年龄- 神经退行性变的相关附带现象，已逐渐被重新定义为一个因果因素，通过新的 描述了神经免疫疾病的机制。星形胶质细胞是大脑中神经胶质细胞的主要类型 由炎症细胞因子诱导采用神经毒性 A1 反应表型，这是我的博士论文实验室 与帕金森病中多巴胺神经元的退化有关。然而，A1 星形胶质细胞的机制 有助于 PD 发病机制的早期事件，例如 α-突触核蛋白 (αSyn) 的病理聚集， 保持未定义。了解这些过程将阐明 A1 星形胶质细胞作为治疗靶点的价值 在早期 PD 中发挥作用，并可能在其他神经退行性疾病和神经免疫性疾病中发挥新作用。我的 初步数据表明，A1 星形胶质细胞表现出对 NLRP3 炎症小体的强烈诱导，NLRP3 炎症小体是 先天免疫系统最近与 αSyn 聚集有关。此外，我已经表明，初级 星形胶质细胞培养物 (1) 可以典型地激活 NLRP3 炎症小体，(2) 容易内化 αSyn，并且 (3) 响应纤维状 αSyn 聚集体，增加 NLRP3 表达和 IL-1β 分泌，与 炎症小体激活。因此，该提案的中心假设是星形胶质细胞NLRP3 炎症小体组装可以驱动致病性 αSyn 聚集，从而增强 NLRP3 激活 和 PD 炎症。在目标 1 中，我们将确定 NLRP3 炎症小体是否促进 αSyn A1 星形胶质细胞聚集。在目标 2 中，我们将通过以下方式研究星形胶质细胞 NLRP3 炎性体激活： 外源性αSyn原纤维。在目标 3 中，我们将证明 αSyn 中星形胶质细胞 NLRP3 激活的致病性 PD 的预成原纤维 (PFF) 小鼠模型。原代星形胶质细胞培养物将用于建立机制 该模型在体外的合理性。我们将使用转基因和基因靶向小鼠来选择性删除 NLRP3 星形胶质细胞并检查对 αSyn PFF 小鼠模型中 PD 病理学的影响。我们的研究将确定 A1 星形胶质细胞通过促进聚集促进早期 PD 发病机制的新机制 αSyn 转化为有毒物质（目标 1），并进一步展示 αSyn 如何激活有效的 NLRP3 炎症 星形胶质细胞中的级联反应（目标 2）。我们还将证明这些过程在良好的环境中具有因果关系 表征 PD 小鼠模型（目标 3）。总的来说，这个项目将增强我们对星形胶质细胞的理解 在 PD 病因学中，并描述了 NLRP3 炎性体在疾病中的新作用。这些研究包括 我作为约翰·霍普金斯大学医学博士/博士生的培训计划的科学背景，这将有助于我 发展成为一名独立的医师科学家。我的赞助商 Ted Dawson 博士/医学博士完全致力于 支持我在这项研究中取得成功以及我的长期职业发展。