Neurokinin-1R Antagonists-Cellular And Molecular Mechanisms

项目2. NK-1 R拮抗剂，包括阿瑞匹坦等，可以在几个不同的水平上中断NK-1 R和CCR 5串扰，包括受体：受体相互作用、信号转导放大、受体合成和表达调节，或间接通过对精氨酸-趋化因子（CCR-5配体）的影响。我们建议，SP信号通过NK-1 R在单核细胞/巨噬细胞中的趋化因子受体CCR 5的调节中具有选择性调节作用。CCR 5和NK-1 R是G蛋白偶联受体（GPCR）。我们假设SP：NK-1 R自分泌环激活信号通路导致 CCR 5介导的信号传导的扩增。此外，NK-1 R对这种自分泌循环的中断 拮抗剂，导致CCR 5受体的功能变化，从而抑制HIV感染和复制。本项目的总体目标是确定SP：NK-1 R相互作用是否通过a）受体水平的GPCR串扰或通过信号传导途径之间的串扰调节CCR 5功能，B）通过受体合成的改变直接影响CCR 5表达，或c）通过细胞因子和趋化因子合成和释放的改变间接影响CCR 5表达。具体目标1：将表征阿瑞匹坦和其他候选NK-1 R拮抗剂对单核细胞/巨噬细胞中CCR 5介导的细胞功能的抗病毒和免疫调节作用。具体目标2：检验NK-1 R 拮抗剂通过G蛋白偶联受体（GPCR）串扰改变CCR 5介导的生理反应。具体目的3：检验NK-1 R拮抗剂中断NK-1 R和CCR 5信号转导通路之间的协同串扰的假设。具体目标4：通过使用siRNA消除巨噬细胞系THP-1中NK-1 R受体表达的敲除研究，进一步确定阿瑞匹坦和其他NK-1 R拮抗剂对NK-1 R受体的特异性。这些研究将确定NK-1 R拮抗剂在单核细胞/巨噬细胞中的特异性/选择性，并指导HIV治疗开发的最佳拮抗剂的选择。

Project. 2. NK-1R antagonists, including aprepitant and others, may interrupt NK-1R and CCR5 crosstalk at several different levels including receptor: receptor interaction, amplification of signal transduction, regulation of receptor synthesis and expression, or indirectly through effects on cytokine-chemokines (CCR-5 ligands). We propose that SP signaling through NK-1R has a selective regulatory role in the regulation of the chemokine receptor CCR5 in monocyte/macrophages. CCR5 and NK-1R are G-protein coupled receptors (GPCRs). We hypothesize that activation of the signaling pathway by the SP:NK-1R autocrine loop results in amplification of CCR5 mediated signaling. Further, the interruption of this autocrine loop by NK-1R antagonists, results in functional changes in the CCR5 receptor resulting in inhibition of HIV infection and replication. The overall goal of this project is to determine whether SP: NK-1R interaction regulates CCR5 function through a) GPCR crosstalk at the level of the receptor or through crosstalk between signaling pathways, b) a direct effect on CCR5 expression through alterations in receptor synthesis, or c) indirectly through alterations in cytokine and chemokine synthesis and release. Specific Aim 1: Will characterize the antiviral and immunomodulating effects of aprepitant and other candidate NK-1R antagonists on CCR5 mediated cellular functions in monocyte/macrophages. Specific Aim 2: Test the hypothesis that NK-1R antagonists alter CCR5 mediated physiological responses through G-protein coupled receptor (GPCR) crosstalk. Specific Aim 3: Test the hypothesis that NK-1R antagonists interrupt synergistic crosstalk between NK-1R and CCR5 signal transduction pathways. Specific Aim 4: Further define the specificity of aprepitant and other NK-1R antagonists for the NK-1R receptor through knockout studies using siRNA to deplete NK-1R receptor expression in the macrophage cell line THP-1. These studies will determine the specificity/selectivity of NK-1R antagonists in monocyte/macrophages and guide selection of the optimal antagonist for HIV therapeutic development.