AGE RELATED CHANGE IN ANGIOTENSIN RECEPTORS AND ITS ROLE IN CHRONIC INFLAMMATION

描述（由申请人提供）：衰老与炎症增强有关。在动物模型中，血管紧张素受体AT1R和AT2R之间比例的改变导致炎症的诱导。衰老对人类AT1R和AT2R表达的影响，以及AT1R和AT2R的变化对老年人炎症增加的贡献，此前尚未得到研究。我们的初步证据表明，体弱的老年人AT1R表达上调，AT2R表达下调，并与IL6有关。我们假设人类脆弱的衰老与免疫系统细胞中AT1R的上调和AT2R表达和功能的下调有关。我们假设这些受体的变化导致免疫系统细胞吞噬能力下降，老年人炎症细胞因子的产生增加，这将进一步加剧AT1R和AT2R表达的差异。为了验证这些假设，我们提出了一项AT1R和AT2R的综合研究，使用来自年轻健康成年人（20-30岁）的免疫系统细胞（淋巴细胞和单核细胞）和四个对照组，包括(1)健壮的老年人（70-90岁），(2)健壮的老年人（70-90岁），(3)虚弱的老年人（70-90岁），(4)虚弱的老年人（70-90岁）接受AT1R阻滞剂治疗。从这些受试者中，我们将收集淋巴细胞和单核细胞，这些细胞将用于以下拟议的研究：采用Q-PCR、western blot、共聚焦显微镜、流式细胞术和Bio-Plex Phosphoprotein Cellular signaling assay检测年轻对照组（20-30岁）和4个对照组（每组N=33）免疫系统细胞中AT1R和AT2R基因表达、蛋白合成和信号通路的变化。通过使用特异性AT1R和/或AT2R阻滞剂培养来自同一个体的免疫系统细胞，并在基线和治疗后用吞噬试验测量单核细胞吞噬功能的变化，评估血管紧张素受体阻断对单核细胞吞噬功能的年龄相关差异和贡献。3. 通过使用特异性AT1R和/或AT2R阻滞剂培养来自同一个体的免疫系统细胞，并在基线和治疗后用ELISA和Bio-Plex细胞因子测定法测量细胞因子，评估AT1R和AT2R对老年个体细胞因子产生的贡献。4. 通过IL-6培养同一受试者的免疫系统细胞，评估炎症对AT1R和AT2R表达和功能的反馈。我们将利用Q-PCR和western blot来量化AT1R和AT2R在IL-6处理后的表达变化。

DESCRIPTION (provided by applicant): Aging is associated with enhanced inflammation. An altered ratio between angiotensin receptors AT1R and AT2R results in induction of inflammation in animal models. The effects of aging on the expression of AT1R and AT2R in humans and the contribution of changes in AT1R and AT2R to increased inflammation in the older have not been previously studied. Our preliminary evidence suggests that frail older adults have up-regulation of AT1R, down-regulation of AT2R expression and implicate for IL6 in this imbalance. We hypothesize that human frail aging is associated with up-regulation of AT1R and down-regulation of AT2R expression and function in immune system cells. We hypothesize that these receptor changes contribute to decreased immune system cells phagocytic capacity and to the increased production of inflammatory cytokines in older individuals which will further heighten the divergence in AT1R and AT2R expression. In order to test these hypotheses, we propose a comprehensive study of AT1R and AT2R using immune system cells (lymphocytes and monocytes) from young, healthy adults (age 20-30) and four comparison groups that consist of (1) robust, older adults (age 70-90), (2) robust, older adults (age 70-90) treated with AT1R blockers, (3) frail, older adults (age 70-90), (4) frail, older adults (age 70-90) treated with AT1R blockers. From these subjects we will collect lymphocytes and monocytes that will be utilized for the following proposed studies: 1. Measure changes in gene expression, protein synthesis, and signaling pathways of AT1R and AT2R in immune system cells from young control (20-30Y) and the four comparison groups (N=33 in each group) using Q-PCR, western blot, confocal microscopy, flow cytometry and Bio-Plex Phosphoprotein Cellular Signaling Assays. 2. Evaluate age-related difference and contribution of Angiotensin receptors blockade to monocytes phagocytic function by incubating immune system cells from the same individuals with specific AT1R and/or AT2R blockers and measuring changes in monocytes phagocytic function with Phagocytosis Assay at baseline and in response to treatment(s). 3. Evaluate contribution of AT1R and AT2R to cytokine production in the older individuals by incubating immune system cells from the same individuals with specific AT1R and/or AT2R blockers and measuring cytokines with ELISA and Bio-Plex cytokine assays at baseline and in response to treatment(s). 4. Assess the feedback of inflammation on AT1R and AT2R expression and function by incubating immune system cells from the same subjects with IL-6. Q-PCR and western blot will be used to quantify the change in expression of AT1R and AT2R in response to IL-6 treatment. PUBLIC HEALTH RELEVANCE: This study is designed to evaluate specific factors that may play a role in late life weakness, increased morbidity and mortality. Angiotensin receptors 1 and 2 (AT1R and AT2R) are found on the surface and on the inside of virtually all human cells. This study will evaluate the relationships among these receptors in immune system cells as people age, and determine how these changes might influence chronic inflammation, frailty and late life vulnerability.