Role of microRNAs in modulating inflammation in alpha-syn mediated models of PD

microRNA 在调节 α-syn 介导的 PD 模型炎症中的作用

• 批准号: 8822142
• 负责人: Aaron Thome
• 金额: $ 3.35万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-04-01 至 2017-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8822142
• 关键词: Affect; Alzheimer' s Disease; Amyotrophic Lateral Sclerosis; Animals; Anti-Inflammatory Agents; Anti-inflammatory; Area; Biological Markers; Brain; Cells; Central Nervous System Diseases; Cerebrospinal Fluid; Chronic; Colony-Stimulating Factor Receptors; Data; Dependovirus; Deposition; Diagnosis; Direct Costs; Disease; Dopamine; Dopaminergic Cell; Down-Regulation; Early Diagnosis; Environment; Enzyme-Linked Immunosorbent Assay; Facilities and Administrative Costs; Gene Expression; Genetic Polymorphism; Genus Malus; HLA-DR Antigens; Health; Human; ITGAM gene; Immune; Immune system; Immunoglobulin G; In Vitro; Inflammation; Inflammatory; Inflammatory Response; Interferon Type II; Interleukin-1; Interleukin-10; Interleukin-6; Knockout Mice; Lymphocyte; Measures; Mediating; Mediator of activation protein; Messenger RNA; MicroRNAs; Microglia; Modeling; Movement Disorders; Multiple Sclerosis; Mus; Nerve Degeneration; Neurodegenerative Disorders; Neurons; Nuclear; PTPRC gene; Parkinson Disease; Pathway interactions; Protein Analysis; Rattus; Regulation; Repression; Role; Severities; Signal Pathway; Signal Transduction; Staining method; Stains; Substantia nigra structure; System; Therapeutic; Transgenic Organisms; Tumor Necrosis Factor-alpha; United States; Untranslated RNA; Up-Regulation; Viral; Virus; adeno-associated viral vector; alpha synuclein; base; cytokine; dopaminergic neuron; genome wide association study; in vivo; in vivo Model; inhibitor/antagonist; interleukin-13 receptor; knockout animal; new therapeutic target; nonhuman primate; novel; overexpression; p65; pars compacta; protein aggregate; response; therapeutic target

Parkinson disease (PD) is the most common neurodegenerative movement disorder and is characterized by progressive loss of dopamine producing neurons in the substantia nigra pars compacta (SNpc) and intracellular aggregates of the protein alpha-synuclein (α-syn). Increasing evidence points to innate immune system activation as an important mediator of disease. Proinflammatory cytokines TNF-α, IL-1β, IL-6, and IFN- γ are elevated in PD post-mortem brain and CSF, and extensive microgliosis is found around areas of degeneration. GWAS studies implicate polymorphisms in the HLA-DR locus in late-onset PD. Transgenic and viral models of PD in mouse, rat, and non-human-primate recapitulate inflammation and neurodegeneration through microgliosis, cytokine expression, lymphocyte invasion, and gradual loss of TH+ cells in the SNpc. MicroRNAs (miRs) are small noncoding RNAs involved in regulating gene expression via repression of mRNA at the post-transcriptional level. Increasing evidence points to miRs as important regulators of the inflammatory environment. Disrupted miR networks affect inflammation in many CNS disorders, such as multiple sclerosis, amyotrophic lateral sclerosis, and Alzheimer disease. Two miRs with an important role in regulating the inflammatory microenvironment in the CNS are miR-124 and miR-155. miR-124 is responsible for maintaining microglial quiescence through a neuron-to-microglia signaling pathway by targeting CEBPα with subsequent PU.1 pathway down-regulation resulting in decreased expression of CD45, M-CSFR, CD11b, F4/80, and MHCII. In contrast to miR-124, miR-155 sustains increased pro-inflammatory signaling by both promoting release of pro-inflammatory cytokines and downregulating anti-inflammatory signaling pathways. FADD, SOCS-1, IKK, IL13Rα1, SMAD-2 and CEBPβ are targets of miR-155, which collectively result in IL-1, IL-6, TNF-α, and iNOS upregulation and IL-10, Arg 1, IL-13R, and TGF-βR pathway downregulation. Using an in vivo model in which α-syn overexpression is produced using adeno-associated virus (AAV), we have observed elevated cytokine expression and IgG deposition at 2 and 4 weeks post transduction with reactive microgliosis at 4 weeks. Subsequent dopaminergic cell loss in the SNpc is observed 6 months post transduction. Using this model, I have obtained data showing an initial reduction of miR-124 expression at 2 weeks post-transduction followed by increased expression at 4 weeks; miR-155 expression is enhanced at 2 weeks. I have also conducted preliminary studies in miR-155 knockout animals; at 4 weeks post-transduction of AAV2-SYN, there was a marked decrease in microgliosis assessed by MHCII staining, compared to WT animals. Our lab has recently shown that MHCII has an important role in α-syn induced neurodegeneration. In the proposed project, I will examine the role of miR-124 and 155 in α-syn induced inflammation both in vitro and in vivo. If these miR’s are important in sustaining the inflammatory response, they could be specific, novel biomarkers capable of providing early diagnosis for PD and can be targeted by novel therapeutic treatments.

帕金森病（PD）是最常见的神经退行性运动障碍，其特征在于： 黑质神经元中产生多巴胺的神经元的进行性损失， 蛋白质α-突触核蛋白（α-syn）的细胞内聚集体。越来越多的证据表明先天免疫 系统激活作为疾病的重要介质。促炎细胞因子TNF-α、IL-1β、IL-6和IFN-γ γ在PD死后脑和CSF中升高，并且在PD死后脑和CSF周围区域发现广泛的小胶质细胞增生。 退化GWAS研究提示HLA-DR位点多态性与晚发性PD有关。转基因和 小鼠、大鼠和非人灵长类动物中的PD病毒模型重现炎症和神经变性 通过SNpc中的小胶质细胞增生、细胞因子表达、淋巴细胞侵袭和TH+细胞的逐渐丧失。 microRNA（miRs）是一种小的非编码RNA，通过抑制基因表达来调节基因表达。 mRNA在转录后水平。越来越多的证据表明，miR是 炎症环境。破坏的miR网络影响许多CNS疾病中的炎症，例如 多发性硬化症、肌萎缩侧索硬化症和阿尔茨海默病。两个miR在以下方面发挥重要作用： 调节CNS中炎性微环境的是miR-124和miR-155。miR-124负责 通过靶向CEBPα，通过神经元-小胶质细胞信号通路维持小胶质细胞静止 随后PU.1途径下调导致CD 45、M-CSFR、CD 11b F4/80和MHCII。与miR-124相反，miR-155通过两种途径维持增加的促炎信号传导。 促进促炎细胞因子的释放并下调抗炎信号通路。 FADD、SOCS-1、IKK、IL 13 R α1、SMAD-2和CEBPβ是miR-155的靶点，它们共同导致IL-1， IL-6、TNF-α和iNOS上调，IL-10、Arg 1、IL-13 R和TGF-βR通路下调。 使用其中使用腺相关病毒（AAV）产生α-syn过表达的体内模型， 我们已经观察到在转导后2周和4周细胞因子表达和IgG沉积升高， 反应性小胶质细胞增生。术后6个月观察到SNpc中的后续多巴胺能细胞损失。 转导使用该模型，我获得的数据显示miR-124的表达在2.5 μ g/ml时开始减少， 在转导后2周，miR-155表达增加，随后在4周时表达增加;在2周时，miR-155表达增加。 周我还在miR-155敲除动物中进行了初步研究;在转导后4周， 与WT相比，AAV 2-SYN的MHCII染色评估的小胶质细胞增生显著减少， 动物我们实验室最近表明MHCII在α-syn诱导的神经退行性变中发挥重要作用。在 在这个项目中，我将在体外研究miR-124和155在α-syn诱导的炎症中的作用， 和体内。如果这些miR在维持炎症反应中很重要，那么它们可能是特异性的、新颖的， 这些生物标志物能够为PD提供早期诊断，并且可以被新的治疗性治疗靶向。