Alcohol abuse in a small rodent neuroAIDS model

描述（由申请人提供）：这是一份R21申请，是对RFA-AA-07-016题为“神经系统功能障碍的机制：酒精滥用对HIV-1神经发病机制的影响（R21）”的回应，该R21申请由美国国家酒精滥用和酒精中毒研究所（NIAAA）发布。本R21申请的基本目标是探索利用多西环素诱导的脑靶向HIV-1 Tat转基因小鼠模型研究酒精滥用- hiv相互作用及其在HIV-1神经发病机制中的作用的可行性。酒精滥用通常发生在感染艾滋病毒之前和之后。几项研究表明，酒精和HIV-1 Tat蛋白（HIV-1感染期间释放的一种病毒蛋白）经常协同作用，表现出相似的神经毒性。尽管取得了这一进展，但酒精与Tat相互作用在HIV神经发病机制中的功能后果尚不清楚。同时，这些研究大多是在体外进行的，实验设计没有考虑到HIV相关的神经发病机制是HIV与所有脑细胞相互作用的结果，包括神经元、星形胶质细胞和内皮细胞。我们最近建立了一种HIV-1 Tat转基因小鼠模型，在该模型中，Tat的表达可以被诱导在大脑中完全表达，并证明在没有HIV-1感染的情况下，大脑中HIV-1 Tat蛋白的表达足以诱导神经行为和神经病理，这些神经行为和神经病理概括了HIV-1感染个体大脑中的一些重要特征（Kim等人，Am.）。[j] .环境科学与技术，2003(2)。因此，在这个探索性的R21期应用中，我们提出表征HIV-1 Tat与体内酒精滥用的相互作用，并确定酒精暴露和Tat表达诱导神经病理的最佳时机。这将为R01应用做准备，其中将确定Tat和酒精之间的神经毒性协同作用的潜在细胞和分子机制以及可能的干预措施。拟议的研究计划包括在不同年龄的小鼠中诱导HIV-1 Tat蛋白的表达，这些小鼠已经以慢性和暴饮暴食的方式预先暴露在酒精中。免疫组织化学染色将用于监测脑病理的变化，包括tat诱导的低密度脂蛋白受体相关蛋白（LRP）配体的细胞外积累、巨噬细胞/单核细胞的CNS浸润和神经元死亡，同时将确定运动功能和条件性位置偏好（CPP）等神经行为后果。

DESCRIPTION (provided by applicant): This is a R21 application in response to RFA-AA-07-016 entitled "Mechanisms of Nervous System Dysfunction: Impact of Alcohol Abuse on HIV-1 Neuropathogenesis (R21)", which was issued by the National Institute on Alcohol Abuse and Alcoholism (NIAAA). The fundamental goal of this R21 application is to explore the feasibility of using our doxycycline (Dox) inducible and brain-targeted HIV-1 Tat transgenic mouse model for studies on alcohol abuse-HIV interaction and its role in HIV-1 neuropathogenesis. Alcohol abuse often occurs prior to and after HIV infection. Several studies suggest that alcohol and HIV-1 Tat protein, a viral protein released during HIV-1 infection, often synergize to exhibit similar neurotoxic properties. Despite this progress, the functional consequences of alcohol interaction with Tat in HIV neuropathogenesis are not well understood. Meanwhile, most of these studies are performed in vitro and the experimental design did not take into consideration the fact that HIV-associated neuropathogenesis is a result of HIV interaction with all brain cells, including neurons, astrocytes and endothelial cells. We have recently established a HIV-1 Tat transgenic mouse model in which Tat expression can be induced to exclusively express in the brain, and demonstrated that expression of HIV-1 Tat protein in the brain in the absence of HIV-1 infection is sufficient to induce neurobehavioral and neuropathologies that recapitulate some important features in the brain of HIV-1-infected individuals (Kim et al., Am. J. Path, 162:1693-707, 2003). Thus, in this exploratory R21 phase application, we propose to characterize HIV-1 Tat interaction with alcohol abuse in vivo and determine the optimal timing of alcohol exposure and Tat expression in inducing neuropathologies. This will be in preparation for a R01 application in which the underlying cellular and molecular mechanisms and possible interventions of this neurotoxicity synergy between Tat and alcohol will be determined. The proposed research plan involves induction of HIV-1 Tat protein expression at different ages of mice that have been pre-exposed to alcohol in both chronic and binge fashions. Immunohistochemistry staining will be used to monitor changes of brain pathologies including Tat-induced extracellular accumulation of low-density lipoprotein receptor-related protein (LRP) ligands, the CNS infiltration of macrophages/monocytes, and neuron death, while neurobehavioral consequences such as locomotor function and conditioned place preference (CPP) will be determined. Public Health Relevance: Individuals with alcohol abuse are more likely to contract HIV, and rates of HIV infection are much higher in alcohol-abusing subjects. Both alcohol abuse and HIV infection often causes a number of brain diseases and affects the ability of people to care for themselves and thus the quality of their daily life. The social and economic impact can not be overemphasized. The current study seeks to establish a small rodent model to characterize alcohol interaction with HIV-1 Tat and ultimately develop therapeutic interventions to prevent and treat neurological diseases resulting from alcohol abuse and HIV infection.