Role of miR-124 in HIV-1 Tat & cocaine mediated microglial activation

miR-124 在 HIV-1 Tat 中的作用

• 批准号: 9411435
• 负责人: Palsamy Periyasamy
• 金额: $ 7.58万
• 依托单位: UNIVERSITY OF NEBRASKA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-07-01 至 2019-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9411435
• 关键词: Animal Model; Anti-Retroviral Agents; Area; Biological Assay; Brain; Cell Culture Techniques; Cell Line; Cells; Cocaine; Cocaine Abuse; Comorbidity; DNA Methylation; Data; Disease; Down-Regulation; Drug abuse; Enzyme-Linked Immunosorbent Assay; Epigenetic Process; Exhibits; Future; Gene Expression Profile; Genetic Transcription; Global Change; Goals; HIV; HIV Envelope Protein gp120; HIV-1; HIV-associated neurocognitive disorder; Health; Immunoprecipitation; In Vitro; Individual; Infection; Inflammation; Inflammatory; Interleukin-1 beta; Interleukin-6; Lead; Life Expectancy; Link; Luciferases; Macaca mulatta; Mediating; Methyl-CpG-Binding Protein 2; Methylation; MicroRNAs; Microglia; Modeling; Modification; Molecular; Molecular Profiling; Mus; Neurodegenerative Disorders; Neuroglia; Neurons; Newborn Infant; Pathogenesis; Pathway interactions; Pharmaceutical Preparations; Pharmacology; Plasma; Prevalence; Process; Proteins; Public Health; Regulation; Research; Role; SIV; STAT3 gene; Signal Transduction; Societies; Substance abuse problem; TNF gene; Testing; Tissues; Trans-Activators; Transfection; Up-Regulation; Validation; Viral Proteins; Viremia; Western Blotting; antiretroviral therapy; cohort; cytokine; drug of abuse; genetic approach; glial activation; lymph nodes; neuroinflammation; overexpression; promoter; pup; sex; symptomatology; therapeutic development; therapeutic target; therapy adherence; therapy development; virus envelope

Project Summary Although the advent of combination antiretroviral therapy (cART) has dramatically increased the life expectancy of people living with HIV-1, paradoxically the prevalence of HIV-1-associated neurocognitive disorders (HAND) in people treated with cART, is on the rise. It is estimated that almost 30-60% of infected individuals on cART will go on to develop HAND, out of which at least 30% will have a co-morbidity of substance abuse. It is well recognized that HIV-1 infection and drug abuse go hand in hand, leading not only to compromised cART adherence but also to exacerbation of HAND. Drugs of abuse and HIV-1 viral proteins (transactivator of transcription - Tat & gp120) have been shown to accelerate HAND pathogenesis co- operatively. Furthermore, similar to HIV-1-positive subjects on cART, SIV-infected rhesus macaques on cART also exhibit increased glial activation, which was associated with dysregulation of various signature microRNAs (miRs). Emerging evidence also points to the role of drugs such as cocaine in mediating glial activation with global changes in miRs. In our preliminary studies, we have demonstrated that exposure of microglial cells to both Tat & cocaine resulted in increased activation of microglia (compared to cells exposed to either agent alone) and this, in turn, was associated with downregulation of brain-enriched miR-124 through an epigenetic pathway (miR-124 promoter DNA methylation) and a concomitant upregulation of MeCP2 (also p-MeCP2), and STAT3 - the predicted targets of miR-124. Furthermore, we also found that overexpression of miR-124 in microglia resulted in alleviation of Tat & cocaine-mediated activation of microglia. The premise of this proposal is that the effect of HIV-1 Tat and cocaine can lead to increased activation of microglia, thereby serving as a model for assessment of broader effects of these agents in the CNS. It is thus hypothesized that Tat & cocaine activate microglia via downregulation of miR-124 involving the unique MeCP2-STAT3 signaling axis. The hypothesis will be tested in two specific aims: AIM 1: Determine the epigenetic mechanism(s) underlying Tat &/or cocaine-mediated downregulation of miR-124 and its association with microglial activation in vitro. AIM 2: Determine the effect(s) of miR-124 overexpression in blocking Tat &/or cocaine-mediated induction of Mg activation in vitro. The findings from this study will set the stage for our long- term future goals (not a part of this study), of validating the cell culture findings in appropriate animal models of HAND & cocaine abuse, and of harnessing the epigenetic modifications associated with Tat & cocaine-induced CNS inflammation as therapeutic targets of HAND.

项目摘要 虽然联合抗逆转录病毒治疗（cART）的出现大大增加了生命， HIV-1感染者的预期，矛盾的是，HIV-1相关的神经认知功能障碍的患病率 在接受cART治疗的人群中，手功能障碍（HAND）的发病率正在上升。据估计，近30-60%的感染者 接受cART治疗的个体将继续发展为HAND，其中至少30%的人将有以下并发症： 滥用药物众所周知，HIV-1感染和药物滥用是密切相关的，不仅导致 损害了cART依从性，也导致了HAND的恶化。药物滥用与HIV-1病毒蛋白 （转录的反式激活因子-达特和gp 120）已被证明可以加速HAND发病机制， 有效地此外，与接受cART的HIV-1阳性受试者类似，接受cART的SIV感染恒河猴 也表现出增加的胶质细胞活化，这与各种标志性microRNA的失调有关。 （miRs）。新出现的证据还指出，药物如可卡因在介导神经胶质细胞活化中的作用， miRs的全球变化。在我们的初步研究中，我们已经证明了小胶质细胞暴露于 达特和可卡因都导致小胶质细胞活化增加（与暴露于任一试剂的细胞相比 单独），这反过来又与通过表观遗传调节脑富集的miR-124下调有关。 途径（miR-124启动子DNA甲基化）和伴随的MeCP 2（也称为p-MeCP 2）上调，以及 STAT 3-miR-124的预测靶点。此外，我们还发现，miR-124的过表达与肿瘤细胞的增殖有关。 小胶质细胞导致达特和可卡因介导的小胶质细胞活化的减轻。此前提 有人提出，HIV-1达特和可卡因的作用可导致小胶质细胞活化增加，从而 作为评估这些药物在CNS中更广泛作用的模型。因此假设， 达特和可卡因通过下调miR-124激活小胶质细胞，涉及独特的MeCP 2-STAT 3 信号轴该假设将在两个特定的目标进行测试：目的1：确定表观遗传 达特和/或可卡因介导的miR-124下调的潜在机制及其与 体外小胶质细胞活化。目的2：确定miR-124过表达在阻断达特和/或 可卡因介导的体外Mg激活诱导。这项研究的结果将为我们长期的研究奠定基础- 在适当的动物模型中验证细胞培养结果的长期未来目标（不是本研究的一部分）， 手和可卡因滥用，并利用与达特和可卡因诱导的 CNS炎症作为HAND的治疗靶点。