LRRK2 Mediated HIV1 Tat Induced Microgliosis is Detrimental to Synapses

LRRK2 介导的 HIV1 Tat 诱导的小胶质细胞增生对突触有害

基本信息

批准号：
8728320
负责人：
Jenna Mae Tabor-Godwin
金额：
$ 5.51万
依托单位：
UNIVERSITY OF ROCHESTER
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-09-28 至 2015-09-27
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8728320
关键词：
Address Affinity Age Antiviral Agents Apoptosis Apoptotic Architecture Axon Biological Assay Blood - brain barrier anatomy Brain Cells Chemotaxis Cognition Disorders DNA Data Defect Dementia Dendritic Spines Development Disease Dose Exposure to Genetic Genetic Transcription HIV HIV-1 Immune response In Vitro Indium Individual Infection Inflammatory Inflammatory Response Injection of therapeutic agent Invaded Knockout Mice Knowledge Laboratories Life Link MAP Kinase Kinase Kinase Mediating Memory Microfluidics Microglia Microscopy Modeling Mus Mutation Nerve Degeneration Neuraxis Neurocognitive Neurons Neurotoxins Parkinson Disease Pathologic Phagocytosis Phosphatidylserines Phosphotransferases Population Production Proteins Reporting Research Signal Transduction Signaling Protein Synapses System Techniques Testing Trans-Activators Transgenic Mice Viral Viral Proteins Virus antiretroviral therapy cellular targeting combat cranium cytokine disability effective therapy improved in vivo insight kinase inhibitor leucine-rich repeat kinase 2 macrophage migration monocyte neuroinflammation neuron apoptosis neurotoxicity new therapeutic target novel optogenetics overexpression postsynaptic presynaptic prevent protein expression research study response small molecule synaptic function two-photon

项目摘要

DESCRIPTION (provided by applicant): Human Immunodeficiency Virus-1 (HIV-1) swiftly infects the central nervous system (CNS) after infection through the migration of infected monocytes and macrophages into the brain (1). After the blood-brain barrier is breached, the virus infects resident microglia, which serve as a CNS reservoir (2). Viral replication and the subsequent immune response eventually leads to cognitive disorders, including dementia, memory defects and altered neuronal signaling (3) (4). The HIV-1 Tat protein is one of the main neurotoxins still produced in the CNS despite the use of combination antiretroviral therapy (cART) (5) (6). Indeed, Tat has been found to induce proinflammatory cytokine responses and neuronal apoptosis (7). Our laboratory utilizes a cortical injection of Tat into the murine CNS to mimic in part pathologic changes associated with HIV-1 associated neurocognitive disorders (HANDs), including sustained neuroinflammation and neurodegeneration within the CNS. Using this model, we have found microgliosis and engulfment of dendritic spines by resident microglia (8). Moreover, we have identified leucine rich repeat kinase 2 (LRRK2) as a novel kinase involved in microglial proinflammatory responses and phagocytosis in response to HIV-1 Tat. LRRK2 is an emerging target in neuroinflammation, as recent studies have linked LRRK2 kinase mutations to Parkinson's disease (9) (10) and microglial proinflammatory cytokine expression (11) (12). Therefore, I hypothesize that HIV-1 Tat increases microglial activation in a LRRK2 dependent manner, and that blocking LRRK2 activity will suppress microgliosis-dependent neurotoxicity during HANDs. In order to test this hypothesis, I will employ a broad analysis of microglial activation both in vitro and in vivo after LRRK2 inhibition using cutting-edge techniques, including in vitro microfluidic chambers and in vivo thin-skull two-photon microscopy. Using a genetic and pharmacologic approach, I will determine how LRRK2 kinase activity alters microglial inflammatory responses and will investigate the ability of a novel small molecule with previously validated high affinity for LRRK2 in cell-free assays, URMC-099, to inhibit microglial LRRK-2 kinase activity. These studies will not only advance our knowledge of how LRRK2 mediates microglial activation, but may help authenticate URMC-099 as an effective treatment for HANDs, as well other neurodegenerative conditions.

描述（由申请人提供）：通过感染的单核细胞和巨噬细胞迁移到大脑中，人类免疫缺陷病毒1（HIV-1）在感染后迅速感染中枢神经系统（CNS）（1）。在破坏血脑屏障之后，该病毒感染了居民小胶质细胞，后者是CNS储层（2）。病毒复制和随后的免疫反应最终导致认知障碍，包括痴呆，记忆缺陷和神经元信号改变（3）（4）。尽管使用了抗逆转录病毒疗法（CART）（5）（6），但HIV-1 TAT蛋白是中枢神经系统中仍产生的主要神经毒素之一。实际上，已经发现TAT诱导促炎性细胞因子反应和神经元凋亡（7）。我们的实验室利用TAT的皮质注射到鼠中枢神经系统中，以模仿与HIV-1相关的神经认知疾病（手）相关的病理变化，包括CNS内持续的神经炎症和神经变性。使用此模型，我们发现了居民小胶质细胞（8）的小胶质细胞增多症和树突状棘的吞噬。此外，我们已经确定了富含亮氨酸的重复激酶2（LRRK2）是一种参与小胶质细胞促炎反应和吞噬作用的新型激酶，以响应HIV-1 TAT。 LRRK2是神经炎症的新兴靶标，因为最近的研究已将LRRK2激酶突变与帕金森氏病联系起来（9）（10）和小胶质细胞促炎细胞因子的表达（11）（12）。因此，我假设HIV-1 TAT以LRRK2依赖性的方式增加了小胶质细胞的活化，并且阻断LRRK2活性会抑制手动期间的小胶质细胞增多依赖性神经毒性。为了检验这一假设，我将使用尖端技术（包括体外微流体室和体内薄膜薄 - 乳房的两光子显微镜检查）对LRRK2抑制后的小胶质细胞激活进行广泛的分析。使用遗传和药理方法，我将确定LRRK2激酶活性如何改变小胶质细胞炎症反应，并将研究新型小的小型炎症反应在无细胞测定中，具有先前验证的对LRRK2的高亲和力的分子，即URMC-099，以抑制小胶质细胞LRRK-2激酶活性。这些研究不仅会提高我们对LRRK2如何介导小胶质细胞激活的了解，而且还可以帮助对URMC-099进行身份验证，以作为手的有效治疗方法，以及其他神经退行性疾病。