A New Model to Dissect the Molecular Mechanisms for ApoE-Associated Lipoprotein Complex Aggregation in the Brain

剖析大脑中 ApoE 相关脂蛋白复合物聚集分子机制的新模型

• 批准号: 10115987
• 负责人: AMANDA MARIA BROWN
• 金额: $ 40.94万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-30 至 2022-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10115987
• 关键词: Adult; Affect; Alleles; Alzheimer' s Disease; Amyloid; Anti-Inflammatory Agents; Apolipoprotein E; Biological Models; Brain; Buffers; Cell Death; Cells; Chronic; Complement; Complex; Dementia; Deposition; Development; Disease; Enzyme-Linked Immunosorbent Assay; Event; Formic Acids; Foundations; Frequencies; Functional disorder; Funding; Gene Expression Profiling; Genes; HIV; HIV Infections; HIV-1; Health; Hippocampus (Brain); Homeostasis; Human; Immune Sera; Immunochemistry; Immunohistochemistry; Impaired cognition; Impairment; In Vitro; Individual; Infection; Inflammation; Inflammatory; Injury; Investigation; Knowledge; Link; Lipoproteins; Microbe; Microglia; Modeling; Molecular; Monkeys; Multiple Sclerosis; Mus; National Institute of Neurological Disorders and Stroke; Nerve Degeneration; Neuraxis; Neurodegenerative Disorders; Neuroglia; Neuroimmune; Neuronal Injury; Neurons; Neuropathogenesis; Neurophysiology - biologic function; Parkinson Disease; Phenotype; Plasma; Population; Positron-Emission Tomography; Process; Proteins; Regulation; Reporting; Reproducibility; Role; Signal Transduction; Signal Transduction Pathway; Stains; Structure; Surface; Testing; Therapeutic; Time; Virus Diseases; brain tissue; cell injury; chronic infection; cost; genetic signature; humanized mouse; in vivo evaluation; interest; knock-down; member; monocyte; mouse model; neurodegenerative phenotype; neuroimaging; novel; osteopontin; pathogen; presenilin; progenitor; protein aggregation; rapid technique; response; single cell sequencing; synuclein; tau Proteins; tau-1; tool

Brain microglia become activated and upregulate pro-(and anti-) inflammatory signaling in response to neuronal cell damage, injury and invasion of the CNS by microbes. Osteopontin (OPN, secreted phosphoprotein-1, SPP1), is highly upregulated in Alzheimer’s disease (AD) and several other neurodegenerative disorders and piqued our interest in pursuing additional mechanistic studies into its function in the central nervous system. An understanding of the molecular mechanisms that underlie the development of the neuropathologic changes and inflammatory processes over time in these disorders remains incompletely understood, and are critical barriers to the development of urgently needed treatments for the growing population of those affected. Interestingly, a “neurodegenerative” microglia gene signature that includes OPN/SPP1 was described for AD. We have been using a mouse model of viral infection as the initial disruptor of brain homeostasis to investigate the role of OPN/SPP1 in neuronal injury and inflammation. We found using translocator protein (TSPO, [11C-DPA-713]) PET-neuroimaging of buffer controls versus HIV-infected humanized mice with knockdown of OPN/SPP1 expression or not, that OPN/SPP1 is a master regulator of microglial inflammatory signaling. A second well characterized marker of activated microglia, Iba-1 was also found by immunohistochemistry (IHC) to be significantly increased. With the prior link of OPN/SPP1 to the neurodegenerative microglia phenotype, we tested whether expression of other members of the reported signature were altered in our mice. To our surprise, we found that antisera against mouse ApoE revealed abundant staining of neurons and glial cells, as well as plaque-like structures and numerous ApoE- associated microparticles in the brains of HIV-infected mice expressing OPN/SPP1, but absent or low in those of HIV-infected OPN-, or OPN+ or OPN- buffer injected mice. We are very excited and believe that our model system, presents for the first time the opportunity to begin to dissect the molecular mechanisms of microglial activation and to test novel hypotheses centered on a regulatory role for OPN/SPP1 in ApoE- associated lipoprotein aggregation and neuropathogenesis. With the central role of microglia in AD, this line of investigation will fill critical gaps in knowledge needed for the advancement of therapeutic approaches aimed at microglia dysfunction.

大脑小胶质细胞被激活并在响应 微生物对CNS的神经元细胞损伤，损伤和侵袭。骨桥（OPN，分泌 磷蛋白1，SPP1）在阿尔茨海默氏病（AD）和其他几个 神经退行性疾病，并激发了我们对其功能进行其他机械研究的兴趣 在中枢神经系统中。对发展基础的分子机制的理解 随着时间的流逝，神经病理学的变化和炎症过程在这些疾病中仍然不完全 理解，这是迫切需要治疗人口的急需治疗的关键障碍 那些受影响的人。有趣的是，包括OPN/SPP1在内的“神经退行性”小胶质细胞基因签名 描述为AD。我们一直使用病毒感染的小鼠模型作为大脑的初始破坏者 稳态研究OPN/SPP1在神经元损伤和炎症中的作用。我们发现使用 易位蛋白（TSPO，[11C-DPA-713]）缓冲液控制的宠物神经影像学与感染HIV感染 人源化小鼠opn/spp1表达是否敲除，opn/spp1是 小胶质细胞炎症信号传导。第二个良好特征的活化小胶质细胞标记，IBA-1也是 通过免疫组织化学（IHC）发现，要显着增加。与OPN/SPP1的先前链接到 神经退行性小胶质细胞表型，我们测试了报告的其他成员的表达是否表达 我们的小鼠签名改变了。令我们惊讶的是，我们发现反对鼠标Apoe的Antisera揭示了 神经元和神经胶质细胞的丰富染色，以及斑块样结构以及许多apoE- 表达OPN/SPP1的HIV感染小鼠的大脑中的相关微粒，但不存在或低 艾滋病毒感染的OPN-或OPN+或OPN缓冲液注射的小鼠的那些。我们非常兴奋，相信我们的 模型系统，首次提出机会开始剖析分子机制 小胶质激活和测试以OPN/SPP1在APOE-的调节作用为中心的新假设 相关的脂蛋白聚集和神经病发生。与小胶质细胞在AD中的核心作用，这条线 投资将填补促进治疗方法所需的知识的关键空白 在小胶质细胞功能障碍处。