Interaction of HIV-Tat and methamphetamine: Role of ion channels and epigenetics

描述（由申请人提供）：甲基苯丙胺（METH）是一种HIV感染患者常用（和滥用）的非法药物。METH会加重HIV相关的神经损伤和脑损伤。临床研究表明，与单独的HIV或METH损伤相比，HIV和METH对神经元损失和神经胶质活化具有累加效应。最近的研究结果也表明APOE 4抑制K+通道活动，而METH诱发动作电位的爆发。APOE 4是APOE的产物吗？4等位基因，是阿尔茨海默病的危险因素。APOE？4等位基因也参与加速HIV疾病的进展。到目前为止，还没有研究APOE基因多态性如何影响HIV感染和METH联合使用时CNS损伤的性质。我们的长期目标是阐明遗传变异的作用及其在HIV感染和这些人通常滥用药物的情况下对大脑的影响。这项工作的目的是更好地了解APOE蛋白，HIV-Tat蛋白和METH之间的相互作用，通过破坏电和生理反应促进神经元损伤。我们的总体假设是，APOE亚型的差异表达将决定HIV-Tat（HIV感染期间）和METH诱导的神经损伤的严重程度，直接影响电活动，从而影响细胞内钙（Ca 2+）稳态。在目的1中，我们将描述HIV+和HIV + METH携带者（？）4+）和非载脂蛋白E携带者？4等位基因（？4-）。我们将确定甲基苯丙胺的使用如何改变APOE启动子和外显子4 CpG岛的DNA甲基化模式的艾滋病毒个体谁是？4+和？4-.在目的2中，我们将通过监测神经元的电活动（Ca 2+、Na+和K+电流和静息膜电位），检查在APOE 3和APOE 4蛋白存在下神经元对达特和METH的反应。为了实现这一点，我们将使用全细胞膜片钳记录（电压钳和电流钳模式）测量宏观Ca 2+，Na+和K+电流和膜电位变化。这些记录将在不同的载脂蛋白E亚型背景下进行，有和没有METH。来自这项研究的数据将构成未来R 01级提案的基础，该新研究者申请人正处于研究生涯的早期阶段。

DESCRIPTION (provided by applicant): Methamphetamine (METH) is an illicit drug commonly used (and abused) by HIV-infected patients. METH exacerbates HIV-related neurological impairments and brain injury. Clinical studies show that HIV and METH have additive effects on neuronal loss and glial activation compared to either HIV or METH insult alone. Recent findings also demonstrate that APOE4 suppress K+ channel activities while METH elicits bursts of action potentials. APOE4, a product of the APOE ?4 allele, is a risk factor for Alzheimer's Disease. The APOE ?4 allele is also implicated in accelerating the progression of HIV Disease. To date, no study has been conducted to investigate how APOE gene polymorphisms affect the nature of CNS injury in the presence of HIV infection and in combination with METH use. Our long-term goal is to elucidate the role of genetic variations and their effects on the brain in the presence f both HIV infection and the drugs commonly abused by these individuals. The objective of this proposed work is to better understand the interactions between APOE protein, HIV-Tat protein and METH in promoting neuronal injury via disruption of electrical and physiological responses. Our overall hypothesis is that differential expression of APOE isoforms will determine the severity of neural damage induced by HIV-Tat (during HIV infection) and by METH by directly influencing electrical activities and consequently affecting intracellular calcium (Ca2+) homeostasis. In Aim 1, we will characterize the DNA methylation patterns of post-mortem brain tissues of HIV+ and HIV + METH individuals who are carriers (?4+) and non-carriers of the APOE ?4 allele (?4-). We will determine how methamphetamine use changes the DNA methylation patterns of the APOE promoter and exon 4 CpG islands in HIV-individuals who are ?4+ and ?4-. In Aim 2, we will examine neuronal responses to Tat and METH in the presence of APOE3 and APOE4 proteins by monitoring neurons' electrical activities (Ca2+, Na+, and K+ currents and resting membrane potentials). To achieve this, we will measure macroscopic Ca2+, Na+, and K+ currents and membrane potentials changes using whole-cell patch clamp recordings (in voltage clamp and current clamp modes). These recordings will be done in different APOE isoform backgrounds with and without METH. The data from this research will form the basis of a future R01-level proposal for this New Investigator applicant who is at the early stage of her research career.