Aldosteronism: An Immunostimulatory State

描述（由申请人提供）：无论其起源如何，无症状（临床前）心室功能障碍最终表现为：循环肾素-血管紧张素-醛固酮系统激活伴症状性充血性心力衰竭（CHF）和全身性疾病伴血浆细胞因子升高、厌食和消瘦（临床）;以及进行性心脏重塑（病理）。 每个阶段涉及的细胞和分子途径仍有待阐明。 我们在大鼠中使用4周的醛固酮（ALDO）治疗，并检查临床前（第1-2周）、临床（第3周）和临床病理（第4周）阶段。 在第4周首次出现在心房和心室中的血管和非血管损伤部位，在侵入的免疫细胞中发现NADPH氧化酶表达和活性的证据，以及NF κ B的激活和编码宿主防御的基因的表达。 通过与螺内酯（Spi）或N-乙酰半胱氨酸（NAC）联合治疗可预防临床和病理分期。 在此，我们假设这种促炎性心脏表型是在外周血单核细胞（PBMC）中发现的免疫刺激状态的结果，该免疫刺激状态由氧/亚硝化应激激活并由PBMC（Mg 2+）i缺乏诱导。 由其他人报道的在饮食Mg 2+缺乏的第3周的心脏病理学同样在第1周的PBMC活化之前发生，并且通过抗氧化剂或P物质受体拮抗剂（L-703，606）（炎症的神经原性介质）来预防。 我们检查了PBMC分子表型（MP），包括所有表达的基因和蛋白质，每周从用ALDO/盐处理4周的大鼠中获得。 mRNA表达的变化揭示了早期（第1周）ATP酶依赖基因的减少和氧化/亚硝化应激的逐步发展，以及持续超过4周的抗氧化防御的上调。 B淋巴细胞反应，包括抗体基因的上调，从wk 1开始出现。蛋白质表达的变化鉴定了早期Mg 2+依赖性Ca 2+泵和过氧化物酶氧还蛋白I的减少。 因此，PBMC的转录组和蛋白质组作为应激和全身免疫刺激状态的早期标志物，预示着疾病和心脏病理的发作。 具体目标：1）监测体内活化的PBMC中的MP，并通过比较在a）标准（stan）或B）缺乏（def）食物、c）标准食物+Mg 2+补充物或d）单独Mg 2+ def食物（无ALDO）中对ALDO/盐加Mg 2+的反应来确定ALDO和Mg 2+的作用; 2）通过研究Spi、NAC或L-703，606的保护作用，监测体内活化的PBMC的MP，并确定与疾病和心脏病理学的出现有关的基因和蛋白质;和3）确定诱导应答ALDO/盐/斯坦霍治疗而出现的促炎性心脏表型所必需的PBMC类型。 这项研究可能会确定预测CHF和心脏重塑发展的临床前标志物，并可能产生治疗策略。

DESCRIPTION (provided by applicant): Irrespective of its origins, asymptomatic (preclinical) ventricular dysfunction eventuates in: activation of the circulating renin-angiotensin-aldosterone system with symptomatic congestive heart failure (CHF) and a systemic illness with elevated plasma cytokines, anorexia & wasting (clinical); and progressive cardiac remodeling (pathologic). Cellular & molecular pathways involved at each stage remain to be elucidated. We use 4wk aldosterone (ALDO) treatment in rats and examine preclinical (wks 1-2), clinical (wk3), and clinicopathologic (wk4) stages. At vascular and nonvascular sites of injury that first appear in both atria & ventricles at wk4, evidence of NADPH oxidase expression and activity is found in invading immune ceils, together with activation of NFkB and expression of genes encoding for host defenses. Clinical and pathologic stages are prevented by co-treatment with spironolactone (Spi) or N-acetylcysteine (NAC). Herein we hypothesize this proinflammatory cardiac phenotype is a result of an immunostimulatory state found in peripheral blood mononuclear cells (PBMC) activated by oxi/nitrosative stress and induced by PBMC (Mg2+)i deficiency. Cardiac pathology, reported by others at wk3 of dietary Mg2+ deficiency, is likewise preceded by PBMC activation at wkl and is prevented by antioxidant or receptor antagonist (L-703,606) to substance P, a neurogenic mediator of inflammation. We examined the PBMC molecular phenotype (MP), including all expressed genes and proteins, obtained weekly from rats treated with ALDO/salt for 4wks. Changes in mRNA expression revealed an early (wk1) reduction in ATPase-dependent genes and a progressive development of oxi/nitrosative stress, and an upregulation of antioxidant defenses sustained over 4wks. B lymphocyte responses, including upregulation of antibody genes, appear from wkl on. Changes in protein expression identified early reduction in Mg 2+-dependent Ca 2+ pump and peroxiredoxin-I. Thus, the transcriptome and proteome of PBMC serve as early markers of stress and the systemic immunostimulatory state heralding the onset of illness and cardiac pathology. Specific Aims: 1) to monitor MP in PBMC activated in vivo and to determine the role of ALDO and Mg2+ by comparing responses to ALDO/salt plus Mg 2+ in a) standard (stan) or b) deficient (def) chows, c) with stan chow+Mg 2+ supplements, or d) Mg 2+ def chow alone (no ALDO); 2) to monitor MP of PBMC activated in vivo and determine genes & proteins involved in the appearance of illness and cardiac pathology by addressing the protective effects of Spi, NAC, or L-703,606; and 3) to determine the type(s) of PBMC necessary for the induction of the proinflammatory cardiac phenotype that appears in response to ALDO/salt/stan chow treatment. This study may identify preclinical markers that predict the development of CHF and cardiac remodeling, and may produce treatment strategies.