Role of Monocyte Oxidative Stress and Mineralocorticoid Receptor Signaling on Cardiovascular Disease and Persistent Inflammation in Antiretroviral-Treated HIV+ Persons

 描述(申请人提供)：在世界范围内，心脏病十多年来仍然是主要的死亡原因，也是美国的主要死亡原因。联合抗逆转录病毒疗法(CART)降低了艾滋病毒相关的发病率和死亡率；然而，这些患者现在面临着新的临床问题，包括增加心血管疾病(CVD)的风险。在美国艾滋病毒携带者中，心血管疾病是与艾滋病无关的主要死亡原因。慢性炎症和髓系细胞失调是心血管疾病和艾滋病毒感染的关键特征，但它们是如何在生物学上联系在一起的仍鲜为人知。我们将在正在进行的HIV和CVD的临床研究中使用HIV+参与者的样本作为模型，以了解可能调节单核细胞反应的因素，这些因素可能导致CVD。核激素受体在单核细胞的激活和分化过程中起着重要作用。我们将评估两种核激素受体，糖皮质激素受体和盐皮质激素受体在低度慢性炎症和在CART抑制的HIV+患者中观察到的心血管疾病风险中的作用。虽然糖皮质激素受体在免疫细胞中具有明确的抗炎功能，但盐皮质激素受体主要在肾上皮细胞中进行研究。相比之下，关于盐皮质激素受体在人类免疫细胞中的表达和功能，以及它与生理和病理生理条件的关系，人们知之甚少。建议的研究利用了我们实验室开发的几种创新的基于流式细胞术的分析方法，这些方法允许同时定量测量糖皮质激素和盐皮质激素受体的表达和功能与免疫细胞表型的关系，以及一种新的基于流式细胞术的定量mRNA分析方法，以测量每个细胞的基因转录。我们将使用这些检测方法来评估皮质醇诱导单核细胞中盐皮质激素受体的激活是否会导致促炎/促纤维化细胞因子的产生，并加速CART抑制的HIV+患者的心血管疾病。我们将使用HIV+参与者的样本进行HIV和CVD的临床研究，以评估氧化应激、炎症和皮质类固醇受体表达以及信号与颈动脉内膜-中层厚度测量之间的关系。然后，我们将使用特定的氧化酶抑制剂、氧化还原敏感型丝氨酸激酶和皮质类固醇受体拮抗剂来探索氧化应激过程中参与盐皮质激素受体信号传递的分子途径。该项目有望为单核细胞中糖皮质激素受体信号的未知领域提供新的见解，不仅将加强我们对CVD发病机制的理解，还将使进一步的机制研究得以开展，以表征免疫细胞中这一重要的信号通路。盐皮质激素受体拮抗剂的可获得性，以及氧化酶和激酶抑制剂的持续开发，进一步增强了这项研究的潜在临床影响，因为有明确的潜在途径可以将这项试验台研究的见解转化为床边研究。

 DESCRIPTION (provided by applicant): Worldwide, heart disease remains the leading cause of death for more than a decade and a leading cause of death in the United States. Combination antiretroviral therapy (cART) has reduced HIV-related morbidity and mortality; however these patients are now facing new clinical issues including increased risk of cardiovascular disease (CVD). Among HIV+ individuals in the United States, CVD is the leading non-AIDS-related cause of death. Chronic inflammation and myeloid cell dysregulation are key features of both CVD and HIV infection, but how they are biologically linked remains poorly understood. We will use specimens from HIV+ participants in ongoing clinical studies of HIV and CVD as a model to understand the factors that may regulate monocyte responses that contribute to CVD. Nuclear hormone receptors play an important role in monocyte activation and differentiation. We will assess the role of two nuclear hormone receptors, the glucocorticoid and mineralocorticoid receptors, for their role in low-grade chronic inflammation and risk of CVD observed in cART- suppressed HIV+ patients. While the glucocorticoid receptor has well-defined anti-inflammatory functions in immune cells, the mineralocorticoid receptor has predominantly been studied in renal epithelial cells. In comparison, very little is known about mineralocorticoid receptor expression and function in human immune cells or its connection with physiologic and pathophysiologic conditions. The proposed studies take advantage of several innovative flow cytometry-based assays developed in our laboratory that allow simultaneous quantitative measures of the glucocorticoid and mineralocorticoid receptor expression and function with immune cell phenotype as well as a novel flow cytometry-based quantitative mRNA assay to measure gene transcripts on a per cell basis. We will use these assays to assess whether cortisol-induced activation of the mineralocorticoid receptor in monocytes results in pro-inflammatory/pro-fibrotic cytokine production and accelerated CVD in cART-suppressed HIV+ patients. We will use specimens from HIV+ participants in ongoing clinical studies of HIV and CVD to assess the relationships between oxidative stress, inflammation and corticosteroid receptor expression and signaling with carotid artery intima-media thickness measures. We will then explore the molecular pathways involved in mineralocorticoid receptor signaling during oxidative stress using specific inhibitors of oxidases, redox-sensitive serine kinases and corticosteroid receptor antagonists. This project is expected to provide novel insights into an unexplored area of corticosteroid receptor signaling in monocytes that will not only strengthen our understanding of this mechanism in CVD pathogenesis, but will also enable the development of additional mechanistic studies to characterize this important signaling pathway in immune cells. The availability of mineralocorticoid receptor antagonists, as well as the ongoing development of oxidase and kinase inhibitors, further enhance the potential clinical impact of this research, as there are clear potential pathways for translating insights from this bench research to the bedside.