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

项目摘要 大约50%的艾滋病毒阳性者发展为艾滋病毒相关的神经认知障碍（HAND）， 正在接受联合抗逆转录病毒治疗（cART）。手是一种炎症性神经退行性疾病 其特征在于受影响的脑中巨噬细胞浸润增加和持续的HIV复制。 个体目前尚无有效的治疗方法。我们的实验室发现 组织蛋白酶B（一种促炎性溶酶体酶）在脑梗死患者死后脑组织中的表达 手此外，HIV-1感染后单核细胞衍生的巨噬细胞（MDM）分泌的组织蛋白酶B 改变与其他蛋白质如血清淀粉样蛋白P组分（SAPC）的相互作用， 神经毒性因此，靶向组织蛋白酶B代表了针对HAND的潜在策略。为了寻找新的 大麻素受体2型（CB2R）的激活抑制了HIV-1的复制 在巨噬细胞中，降低血脑屏障（BBB）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， CB2R在体外HIV感染的巨噬细胞和HAND患者的死后脑组织中。因此本 受体是治疗HAND的有希望的靶点。然而，CB2R激活在 组织蛋白酶B分泌和神经毒性以前没有研究过。本提案的总体目标是 目的是了解CB2 R在组织蛋白酶B分泌中的激活机制和HIV感染后的神经毒性。 巨噬细胞我们的中心假设是，CB2 R激活将阻止组织蛋白酶B分泌和神经毒性 通过减弱MDM中的细胞内炎症通路和预防 组织蛋白酶B与SAPC的相互作用。我们的假设是基于以下结果制定的： 用CB2 R激动剂治疗的HIV感染的MDM的组织蛋白酶B分泌减少和神经毒性。我们 我将检验我们的中心假设，从而通过以下努力实现本提案的目标 具体目的：1）确定CB2 R活化在组织蛋白酶B分泌中的作用和来自HIV-1的神经毒性。 感染的巨噬细胞2)探索细胞内途径并表征组织蛋白酶B相互作用组在 CB2R活化后HIV感染的巨噬细胞的上清液。3)了解慢性病的发病机制 手发炎。这项拟议研究的基本原理是了解CB 2 R激活的作用 在组织蛋白酶B分泌和相互作用中的作用将允许开发针对HIV诱导的组织蛋白酶的策略 B神经毒性。这一贡献是重要的，因为它将提供有关的机制， 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， 制定新的策略来对付HAND。

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.