HIV and Methamphetamine-Associated Alterations of Behavior and Neural Networks

HIV-1和冰毒都能引起行为改变和脑损伤，但人们对它们之间的相互作用知之甚少。在目前的资助期内，我们观察到一次性冰毒暴饮仅在HlV/gp120转基因（tg）小鼠中引起海马破伤风后增强的减少，而对照组小鼠则没有。RNA表达研究表明，HIVgp120和甲基安非他明均可引起谷氨酸能和gaba能神经传递的显著变化。体外研究表明，100 pM的甲基安非他明增加HIVgp120的神经毒性和兴奋毒性NMDA。甲基安非他明还增加了人巨噬细胞的HIV感染，这与至少四种干扰素诱导基因的下调有关。因此，总体假设是使用甲基苯丙胺会加重与HIV-1感染相关的行为障碍和神经毒性。我们的具体目标是：(1)通过研究与HlVgp120-和iTat-tg以及非tg对照小鼠中甲基苯甲胺长期效应相关的基因表达来识别受影响的神经网络，并将这种基因表达变化与行为表现联系起来；(2)确定甲基安非他明是否会干扰cART药物减少病毒复制和感染单核/巨噬细胞产生神经毒性产物的功效。对于Aim 1， gp120-和iTat-tg和非tg对照小鼠将接受一种新的慢性低剂量12周冰毒治疗方案。经过5个月的戒断期和行为测试，将使用反褶积显微镜、芯片和qRT-PCR分析脑组织中神经元和胶质细胞的损伤和基因表达。基因表达数据将分别分析皮质、海马体、纹状体等脑区，并与行为结果和神经病理学相关联。基因表达分析的后续研究将利用生化和显微镜方法探测蛋白质的表达、定位和功能。对于Specific Aim.2，感染HIV的巨噬细胞将接受ARV联合治疗和不同浓度的甲基安非他明治疗。巨噬细胞实验上清的神经毒性将在大鼠小胶质细胞缺失的混合神经胶质脑皮质细胞上进行测试。长期目标是确定神经毒性机制，作为治疗干预的潜在目标。

Both HIV-1 and METH can cause behavioral changes and brain injury, but their interaction is poorly understood. In the current funding period, we observed that a one-time METH binge caused a reduction in hippocampal post-tetanic potentiation only in HlV/gp120-transgenic (tg) but not control mice. RNA expression studies indicated that both HIVgp120 and METH trigger significant changes of glutamatergic and GABAergic neurotransmission. In vitro studies showed that METH at 100 pM increased neurotoxicity of HIVgp120 and excitotoxic NMDA. METH also increased HIV infection of human macrophages in association with down-regulation of at least four interferon-inducible genes. Therefore, the overall hypothesis is that use of METH aggravates behavioral disturbances and neurotoxicity associated with HIV-1 infection. Our Specific Aims are to: (1) identify affected neural networks by studying gene expression associated with long-term effects of METH in HlVgp120- and iTat-tg and non-tg control mice and to relate such gene expression changes to behavioral performance; (2) determine whether METH interferes with the efficacy of cART drugs to reduce viral replication and production of neurotoxic products by infected monocytes/macrophages. For Aim 1, gp120- and iTat-tg and non-tg control mice will be treated with a novel chronic, low dose 12-week METH regimen. Following a 5-month abstinence period and behavioral testing, neuronal and glial injury and gene expression will be analyzed in brain tissue using deconvolution microscopy, microarray and qRT-PCR. Gene expression data will be analyzed separately for cortex, hippocampus, striatum and other brain regions, and correlated with behavioral outcomes and neuropathology. Follow-up studies to gene expression analyses will probe protein expression, localization and function using biochemical and microscopy approaches. For Specific Aim.2, macrophages infected with HIV will be treated with ARV combinations and varying METH concentrations. The neurotoxicity of supernatents from such macrophage experiments will be tested on rat microglia depleted mixed neuronal glial cerebrocortical cells. The long-term objective is to identify neurotoxic mechanisms that are potential targets for therapeutic intervention.