Role of the myeloid mineralocorticoid receptor in vascular inflammation in atherosclerosis

项目总结/摘要 尽管在治疗和预防方面取得了进展，但心血管缺血性事件仍然是心血管疾病的主要原因。 世界上的死亡。盐皮质激素受体（MR）的激活与慢性炎症相关， 血管壁和动脉粥样硬化斑块的形成，动脉粥样硬化斑块导致缺血性事件， 破裂并随后阻塞流向靶器官的血流。MR拮抗剂已被证明可以减少 在临床试验中降低心血管相关死亡率以及减少动脉粥样硬化斑块大小和炎症 独立于血压变化的小鼠模型。以前的研究探讨了 血管细胞MR与动脉粥样硬化。内皮细胞MR缺乏，而平滑肌细胞无 减轻动脉粥样硬化斑块炎症，但既没有复制的比例的变化， 斑块中的炎性髓样细胞，如全身MR阻断所见。髓系细胞中的MR 已显示My-MR在体外调节巨噬细胞（MΦ）中的促炎基因表达， 在小鼠模型中，My-MR有助于斑块大小，但My-MR直接有助于血管生成的机制 动脉粥样硬化中炎症是未知的。我们已经证明了慢滚动白细胞的数量 在肠系膜血管系统中，对TNFα的反应随着My-MR缺乏而降低。此外，数字 动脉粥样硬化斑块中MΦ和T细胞的数量随着My-MR的缺乏而减少。因此，我们假设， My-MR通过调节髓样细胞向血管壁的募集（MΦ）而促进斑块炎症 极化和增殖，以及体内斑块中MΦ与效应T细胞的相互作用。我们已经开发 - 动脉粥样硬化小鼠模型，其中MR在髓样细胞中特异性缺失（而不是在淋巴细胞中， 任何其他血管细胞）。在目的1中，我们将确定My-MR在调节MΦ募集和 通过活体显微镜、流式细胞术和组织学观察动脉粥样硬化斑块内的增殖。在Aim中 2、探讨My-MR在调节MΦ共刺激分子和细胞因子信号传导中的作用， 因此，使用流式细胞术、条件培养基和共培养， 实验这些目标的成功完成将阐明My-MR介导的调节MΦ的途径 功能和整体斑块环境。这些研究有望揭示潜在的免疫功能 预防心血管疾病的目标。该提案还包括一份详细的培训计划， 整合临床培训，为PI作为独立医生科学家的职业生涯做好准备。

PROJECT SUMMARY/ABSTRACT Despite advances in therapeutics and prevention, cardiovascular ischemic events remain the leading cause of death in the world. Activation of the mineralocorticoid receptor (MR) is associated with chronic inflammation of the blood vessel wall and formation of atherosclerotic plaques that lead to such ischemic events following their rupture and subsequent occlusion of blood flow to target organs. MR antagonists have been shown to reduce cardiovascular-related mortality in clinical trials as well as reduce plaque size and inflammation in atherosclerosis mouse models independently of changes in blood pressure. Previous studies have explored the contributions of MR in vascular cells to atherosclerosis. Deficiency of MR in endothelial cells but not smooth muscle cells attenuates atherosclerotic plaque inflammation, but neither reproduced changes in the proportion of pro- inflammatory myeloid cells in the plaque as seen with systemic MR blockade. MR in cells of the myeloid lineage (My-MR) has been shown to regulate pro-inflammatory gene expression in macrophages (MΦ) in vitro and contribute to plaque size in mouse models, but the mechanisms by which My-MR directly contributes to vascular inflammation in atherosclerosis are not known. We have demonstrated that the number of slow-rolling leukocytes in the mesenteric vasculature in response to TNFα decreases with My-MR deficiency. Additionally, the numbers of MΦ and T cells in atherosclerotic plaque decrease with My-MR deficiency. Therefore, we hypothesize that My-MR contributes to plaque inflammation by modulating myeloid cell recruitment to the vessel wall, MΦ polarization and proliferation, and MΦ interactions with effector T cells in the plaque in vivo. We have developed an atherosclerosis mouse model in which MR is specifically deleted in myeloid cells (and not in lymphocytes or any other vascular cells). In Aim 1, we will determine the role of My-MR in regulating MΦ recruitment to and proliferation within atherosclerotic plaques in vivo by intravital microscopy, flow cytometry, and histology. In Aim 2, we will explore the role of My-MR in regulating MΦ co-stimulatory molecule and cytokine signaling and therefore T cell function both in vivo and in vitro using flow cytometry, conditioned media, and co-culture experiments. Successful completion of these aims will elucidate My-MR-mediated pathways that regulate MΦ function and the overall plaque environment. These studies are expected to reveal potential immunotherapeutic targets for the prevention of cardiovascular disease. This proposal also includes a detailed training plan and integration of clinical training to prepare the PI for a career as an independent physician scientist.