Modulation of alpha-7 nicotinic acetylcholine receptor in HIV-infected microglia and brain organoids

项目摘要 大约50%的艾滋病毒阳性者会患上艾滋病毒相关的神经认知障碍(HAND)，尽管 正在接受联合抗逆转录病毒治疗(CART)。手部是一种炎症性神经退行性疾病 以巨噬细胞浸润增加和HIV在患者脑内持续复制为特征 个人。目前还没有针对手部疾病的有效治疗方法。我们实验室发现增加了 组织蛋白酶B在人死后脑组织中的表达 手。此外，HIV-1感染单核细胞来源的巨噬细胞(MDM)后，分泌组织蛋白酶B 改变与其他蛋白质的相互作用，如血清淀粉样蛋白P成分(SAPC)并促进 神经毒性。因此，靶向组织蛋白酶B代表了一种潜在的针对HAND的策略。在寻找新的 治疗方法表明，激活大麻素2型受体(CB2R)可以抑制HIV-1的复制 在巨噬细胞中，降低血脑屏障(BBB)的通透性，降低对HIV-1病毒蛋白的神经毒性， 并减少促炎细胞因子的释放。尽管如此，研究表明， 在体外HIV感染的巨噬细胞和手部患者的死后脑组织中存在CB2R。因此，这 受体是治疗手部疾病的一个有前途的靶点。然而，CB2R的激活在 组织蛋白酶B的分泌和神经毒性以前还没有研究过。这项提案的总体目标是 是为了了解组织蛋白酶B分泌中CB2R激活的机制和HIV感染的神经毒性 巨噬细胞。我们的中心假设是CB2R的激活将阻止组织蛋白酶B的分泌和神经毒性 通过减轻MDM细胞内炎症途径和预防HIV感染的巨噬细胞 组织蛋白酶B与SAPC的相互作用。我们的假设是基于结果提出的，这些结果表明 用CB2R激动剂治疗HIV感染的MDM后，组织蛋白酶B的分泌减少和神经毒性。我们 将检验我们的中心假设，从而通过追求以下内容来实现本提案的目标 具体目标：1)确定CB2R激活对组织蛋白酶B分泌的影响和HIV-1的神经毒性。 感染的巨噬细胞。2)探索组织蛋白酶B相互作用的细胞内途径和特征 HIV感染的巨噬细胞CB2R激活后的上清液。3)了解慢性精神分裂症的发病机制 手头有炎症。这项拟议研究的基本原理是，理解CB2R激活的作用 在组织蛋白酶B的分泌和相互作用中，将允许制定对抗艾滋病毒诱导的组织蛋白酶的策略 B神经毒性。这一贡献意义重大，因为它将提供关于 CB2R在组织蛋白酶B诱导的HIV感染巨噬细胞神经毒性中的调节作用，并将有助于 制定新的反手战略。

Project Summary Approximately, 50% of HIV-positive people develop HIV-associated neurocognitive disorders (HAND), despite being under combined antiretroviral therapy (cART). HAND is an inflammatory neurodegenerative disease characterized by increased macrophage infiltration and persistent HIV replication in the brain of affected individuals. There are no effective therapies available against HAND. Our laboratory has found increased expression of cathepsin B, a pro-inflammatory lysosomal enzyme, in postmortem brain tissues of individuals with HAND. In addition, after HIV-1 infection of monocyte-derived macrophages (MDM), secreted cathepsin B changes interactions with other proteins such as serum amyloid P component (SAPC) and promotes neurotoxicity. Thus, targeting cathepsin B represents a potential strategy against HAND. In search for new therapies, it was demonstrated that activation of cannabinoid receptor type 2 (CB2R) inhibits HIV-1 replication in macrophages, reduces blood-brain barrier (BBB) permeability, decreases neurotoxicity to HIV-1 viral proteins, and diminishes pro-inflammatory cytokines release. Nonetheless, studies have shown increased expression of CB2R in in vitro HIV-infected macrophages, and in post-mortem brain tissues of HAND patients. Therefore, this receptor represents a promising target for treatment against HAND. However, the role of CB2R activation in cathepsin B secretion and neurotoxicity has not been studied previously. The overall objective of this proposal is to understand the mechanisms of CB2R activation in cathepsin B secretion and neurotoxicity from HIV-infected macrophages. Our central hypothesis is that CB2R activation will prevent cathepsin B secretion and neurotoxicity from HIV-infected macrophages by attenuating intracellular inflammation pathways in MDM and preventing cathepsin B interactions with SAPC. Our hypothesis was formulated based on results that show a significant decrease in cathepsin B secretion and neurotoxicity from HIV-infected MDM treated with a CB2R agonist. We will test our central hypothesis and, thereby, accomplish the objective of this proposal by pursuing the following specific aims: 1) Determine the effect of CB2R activation in cathepsin B secretion and neurotoxicity from HIV- infected macrophages. 2) Explore the intracellular pathways and characterize cathepsin B interactome in supernatants from HIV-infected macrophages after CB2R activation. 3) Understand the mechanisms of chronic inflammation in HAND. The rationale for this proposed research is that understanding the role of CB2R activation in cathepsin B secretion and interactions will permit the development of strategies against HIV-induced cathepsin B neurotoxicity. This contribution is significant because it will provide new knowledge about the mechanisms of CB2R modulation in cathepsin B-induced neurotoxicity from HIV-infected macrophages, and will contribute to the development of new strategies against HAND.