The regulation of cannabinoid receptors in microglial cells during HIV infection

HIV感染过程中小胶质细胞大麻素受体的调节

基本信息

批准号：
8227978
负责人：
Catalin Filipeanu
金额：
$ 14.2万
依托单位：
LSU HEALTH SCIENCES CENTER
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-04-01 至 2013-09-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8227978
关键词：
Accounting Acquired Immunodeficiency Syndrome Adrenergic Receptor Affect Agonist Arrestins Binding Biological Cannabinoids Cells Chronic Chronic Disease Cognitive Cyclic AMP Data Dementia Development Disease Disease Progression Drug Delivery Systems Eating Foundations G-Protein-Coupled Receptors GTP-Binding Proteins HIV HIV Infections HIV-1 Health Sciences Heart failure Highly Active Antiretroviral Therapy Hippocampus (Brain)Human Illicit Drugs Immune Immune response Incidence Infection Inflammatory Ligands MAP Kinase Gene Macaca mulatta Marijuana Mediating Microglia Neuraxis Neuroglia Neuronal Plasticity Neurons Outcome Patients Pharmaceutical Preparations Phase Play Process Proteins Receptor Activation Receptor Signaling Regulation Role SIV Scaffolding Protein Signal Pathway Signal Transduction Symptoms Syndrome Testing Tetrahydrocannabinol Time United States Up-Regulation Viral Load result Virus Diseases animal extract arrestin 2 base cannabinoid receptor cell type design improved in vivo mortality novel therapeutics public health relevance receptor receptor expression research study

项目摘要

DESCRIPTION (provided by applicant): There are over one million people in the United States infected with HIV, and due to the introduction of highly active antiretroviral therapy, HIV infection has become a chronic disease frequently co-existing with chronic use of prescribed, experimental, and illicit drugs, including marijuana. In addition to being the most potent psychoactive component of marijuana, 9-tetrahydrocannabinol (THC) has many other biological actions including modulation of the immune response, neuronal plasticity and food intake. These actions are mediated by interactions with at least three specific receptors (CB1R, CB2R and GPR55) that are expressed in the central nervous system (CNS). However, there are currently no data on the effects of HIV-infection on expression levels and signaling of cannabinoid receptors, or on the effects of cannabinoid receptor activation on the progression of HIV-infection. In our recent studies we observed that long-term THC treatment in SIV- infected rhesus macaques was found to have beneficial effects like decreasing viral load and decreasing early mortality. To test if these effects were due to changes in cannabinoid receptor expression, CB1R and CB2R protein levels were determined in hippocampal extracts. Surprisingly, SIV-infection has differential effects, CB1R levels being reduced to 42 1 8 %, whereas CB2R levels were increased with 53 1 10%. To elucidate the cellular mechanisms underlying these changes, this project will focus on the effects of HIV-1 on the cannabinoid receptors in microglial cells, as these are main immune cells at this level, playing major roles in HIV1-associated dementia (HAD), which affects 10-20 % of AIDS patients. In preliminary experiments we found that both CB1R and CB2R are expressed in human primary microglial cells, but only CB2R levels were upregulated four days post HIV-1 infection. Despite this increase, the effects of CB2R stimulation on the cAMP levels were blocked by HIV-1 infection. In contrast, CB1R activation did not change cAMP levels, but MAPK activation by this receptor was apparent only after HIV-1 infection. In addition, we found that the cellular levels of the scaffold protein 2-arrestin were upregulated after HIV-1 infection, possibly contributing to the observed changes in the cannabinoid signaling. Based on these observations we hypothesize that HIV-1 infection changes the expression levels and signaling of cannabinoid receptors in microglial cells, at least in part by altering 2-arrestin cellular levels. In the Specific aim 1 we will test if HIV-1 infection specifically increases the CB2R levels in human microglial cells, and in the Specific Aim 2 we will test if HIV-1 infection alters the CB1R- and CB2R-mediated effects on cAMP and MAPK levels through alterations in the cellular 2-arrestin levels. When completed, the results from these studies will show for the first time that HIV-1 infection modulates the expression and signaling of cannabinoid receptors in human microglial cells and these data will also provide a clearer understanding of the cellular mechanisms contributing to HIV disease progression in CNS and possibly identify new therapeutics for HIV infection by identifying new drug targets for the treatment of HAD. PUBLIC HEALTH RELEVANCE: The number of microglial cells, the main immunological cell type present in CNS, are increasing during inflammatory processes, including HIV infection, and it has been proposed that the activation of these cells contribute to HIV1-associated dementia (HAD), which has an incidence of 10-20% in AIDS patients. The function of the cannabinoid receptors, proteins which are present in these cells and recognize the main active compound from marijuana, as well as other compounds which are naturally present in the body, has not been investigated in AIDS, although there are indications that drugs interfering with the activity of the cannabinoid receptors may produce positive outcomes in the inflammatory diseases. This application will characterize the regulation of cannabinoid receptor number and function in control and HIV1 infected microglial cells, providing foundation for development of new treatments in AIDS, particularly in HAD.

描述（由申请人提供）：美国有超过一百万人感染艾滋病毒，由于高效抗逆转录病毒疗法的引入，艾滋病毒感染已成为一种慢性疾病，经常与长期使用处方、实验性药物并存。，以及非法药物，包括大麻。 9-四氢大麻酚 (THC) 除了是大麻中最有效的精神活性成分外，还具有许多其他生物作用，包括调节免疫反应、神经元可塑性和食物摄入。这些作用是通过与中枢神经系统 (CNS) 中表达的至少三种特定受体（CB1R、CB2R 和 GPR55）的相互作用介导的。然而，目前还没有关于 HIV 感染对大麻素受体表达水平和信号传导的影响，或大麻素受体激活对 HIV 感染进展影响的数据。在我们最近的研究中，我们发现对感染 SIV 的恒河猴进行长期 THC 治疗具有有益效果，例如降低病毒载量和降低早期死亡率。为了测试这些影响是否是由于大麻素受体表达的变化造成的，我们测定了海马提取物中的 CB1R 和 CB2R 蛋白水平。令人惊讶的是，SIV 感染具有不同的影响，CB1R 水平降低至 42·1·8%，而 CB2R 水平则增加了 53·1·10%。为了阐明这些变化背后的细胞机制，该项目将重点研究 HIV-1 对小胶质细胞中大麻素受体的影响，因为这些是该水平的主要免疫细胞，在 HIV1 相关痴呆 (HAD) 中发挥着重要作用。影响 10-20% 的艾滋病患者。在初步实验中，我们发现CB1R和CB2R在人原代小胶质细胞中表达，但只有CB2R水平在HIV-1感染后四天上调。尽管有这种增加，但 CB2R 刺激对 cAMP 水平的影响被 HIV-1 感染所阻断。相比之下，CB1R 激活不会改变 cAMP 水平，但该受体对 MAPK 的激活仅在 HIV-1 感染后才明显。此外，我们发现 HIV-1 感染后支架蛋白 2-arrestin 的细胞水平上调，可能导致观察到的大麻素信号传导的变化。基于这些观察结果，我们假设 HIV-1 感染改变了小胶质细胞中大麻素受体的表达水平和信号传导，至少部分是通过改变 2-arrestin 细胞水平来实现的。在特定目标 1 中，我们将测试 HIV-1 感染是否会特异性增加人类小胶质细胞中的 CB2R 水平，在特定目标 2 中，我们将测试 HIV-1 感染是否会改变 CB1R 和 CB2R 介导的对 cAMP 和 MAPK 的影响通过改变细胞 2-arrestin 水平来调节 2-arrestin 水平。完成后，这些研究的结果将首次表明 HIV-1 感染调节人类小胶质细胞中大麻素受体的表达和信号传导，这些数据还将提供对导致 HIV 疾病进展的细胞机制的更清晰的了解。 CNS 并可能通过确定治疗 HAD 的新药物靶点来确定 HIV 感染的新疗法。公共卫生相关性：小胶质细胞是中枢神经系统中存在的主要免疫细胞类型，在包括 HIV 感染在内的炎症过程中，小胶质细胞的数量不断增加，并且有人提出，这些细胞的激活会导致 HIV1 相关痴呆 (HAD)。艾滋病患者中的发病率为10-20%。大麻素受体（存在于这些细胞中并识别大麻主要活性化合物以及体内天然存在的其他化合物的蛋白质）的功能尚未在艾滋病中进行研究，尽管有迹象表明药物干扰大麻素受体的活性可能对炎症性疾病产生积极的结果。该应用将表征对照和 HIV1 感染的小胶质细胞中大麻素受体数量和功能的调节，为开发艾滋病（特别是 HAD）新疗法奠定基础。