Mechanisms underlying dysregulated neuroimmune signaling and neuronal dysfunction in HIV (+) individuals with cART and cocaine

摘要： 持续的神经炎症和突触树突损伤是NeuroHIV的两个标志性特征。 导致这些病理变化的因素包括低水平的残留HIV复制/HIV蛋白和/或 cART本身的毒性。众所周知，药物滥用，特别是可卡因滥用，是一种常见的并发症， 艾滋病毒感染。有趣的是，可卡因也被证明会加剧神经炎症， 直接作用于免疫细胞，如小胶质细胞和/或降低cART的有效性。因此可以 他们设想，在中枢神经系统内，HIV蛋白、滥用药物和cART的组合创造了一个有毒的环境 通过促炎因子促进神经炎症和异常神经胶质-神经元串扰的恶化 调解员神经免疫信号转导失调的详细分子通路， 然而，随后突触树突损伤仍然是难以捉摸的。我们的初步研究表明： 1)HIV达特可通过NLRP 3炎性体信号传导增加小胶质细胞活化; 2）可卡因活化 小胶质细胞通过失调的自噬途径，和3）临床使用的抗逆转录病毒鸡尾酒（TFV， FTC、DTG）损害小胶质细胞溶酶体功能，导致其活化。此外，我们还 表明IL 1 β，NLRP 3炎性体激活途径的产物，上调谷氨酸 受体离子型NMDA（GRINS），并伴随着减少初级神经元的棘密度。的 因此，本申请的前提是HIV达特、可卡因和ARV的组合可以通过以下途径激活小胶质细胞： NLRP 3炎性体和自噬途径，以及IL 1 β释放增加。反过来， 会导致神经元功能障碍使用体外和体内（HIV转基因大鼠）方法，我们将 通过三个具体目标检验假设-SA 1：研究达特的分子机制， 可卡因和ARV（3种药物方案）介导的体外小胶质细胞活化; SA 2：研究 IL-1 β诱导神经元兴奋性毒性的机制& SA 3：观察NLRP 3在体内的变化 炎症小体和自噬信号传导以及lncRNA malat 1/NF-κB/GRIN轴与 给予可卡因和cARV的HIV-Tg大鼠的行为缺陷。两名经验丰富的PI（郭博士和布赫博士）将 共同领导该项目，以实现拟议目标。本R 01申请，响应RFA-MH-18-610 标题为“艾滋病病毒诱导的中枢神经系统（CNS）中的神经元回路、受体和网络改变” 功能障碍，”旨在探索神经免疫功能失调的分子机制， 由HIV蛋白、滥用药物和cRAT引起的信号传导影响神经元受体的功能。

Abstract: Sustained neuroinflammation & synaptodendritic injury are the two hallmark features underlying NeuroHIV. Factors contributing to these pathological changes include low-level residual HIV replication/HIV proteins and/or toxicity of cART itself. It is well-recognized that drug abuse, specifically cocaine abuse, is a common comorbidity of HIV infection. Intriguingly, cocaine has also been shown to exacerbate neuroinflammation either through its direct effects on immune cells, such as microglia and/or by decreasing the effectiveness of cART. It can thus be envisioned that within the CNS, combinations of HIV proteins, abused drugs and cART create a toxic milieu promoting exacerbated neuroinflammation and abnormal glial-neuronal cross-talk via the pro-inflammatory mediators. The detailed molecular pathways underlying the dysregulated neuroimmune signaling and subsequent synaptodendritic injury, however, remain elusive. Our preliminary studies have demonstrated that: 1) HIV TAT can increase microglial activation via the NLRP3 inflammasome signaling; 2) cocaine activates microglia via the dysregulated autophagy pathway, & 3) Combination of clinically used antiretroviral cocktail (TFV, FTC, DTG) impaired microglial lysosome functions leading to their activation. Furthermore, we also demonstrated that IL1β, product of the NLRP3 inflammasome activation pathway, upregulated the glutamate receptor ionotropic NMDAs (GRINS) and concomitantly decreased spine density in primary neurons. The premise of this application thus is that combinations of HIV TAT, cocaine & ARVs can activate microglia via the NLRP3 inflammasome & autophagy pathways, and that the increased release of IL1β. In turn, contributes to neuronal dysfunction. Using both in vitro and in vivo (HIV transgenic rats) approaches we will test the hypothesis via three specific aims - SA1: Investigate the molecular mechanism(s) underlying TAT, cocaine, & ARVs (3 drug regimen)-mediated activation of microglia in vitro; SA2: Investigate the molecular mechanism(s) underlying IL1β-induced neuronal excitotoxicity & SA3: Validate in vivo the changes in NLRP3 inflammasome and autophagy signaling and also lncRNA malat1/NF-κB/GRINs axis in conjunction with behavioral deficits in HIV-Tg rats administered cocaine and cARV. Two experienced PIs (Drs. Guo & Buch) will co-lead this project to accomplish the proposed goals. This R01 application, in response to RFA-MH-18-610 titled “Altered neuronal circuits, receptors and networks in HIV-induced Central Nervous System (CNS) dysfunction,” aims to explore the molecular mechanisms underlying how the dysregulated neuroimmune signaling caused by HIV proteins, drugs of abuse, & cRAT impacts the function of neuronal receptors.