Aldosteronism: An Immunostimulatory State

描述(申请人提供)：无论起源如何，无症状(临床前)心功能障碍最终导致：循环肾素-血管紧张素-醛固酮系统激活，伴随症状性充血性心力衰竭(CHF)和伴随血浆细胞因子升高的全身性疾病，厌食和消瘦(临床)；和进行性心脏重构(病理)。每一阶段所涉及的细胞和分子途径仍有待阐明。我们使用4wk的醛固酮(aldosterone，ALDO)治疗大鼠，检查临床前(WKS 1-2)、临床(WK3)和临床病理(WK4)阶段。在WK4时首先出现在房室的血管和非血管损伤部位，在入侵的免疫细胞中发现了NADPH氧化酶表达和活性的证据，以及NFkB的激活和编码宿主防御的基因的表达。临床和病理分期可通过与螺内酯(SPI)或N-乙酰半胱氨酸(NAC)联合治疗来预防。在此，我们假设这种促炎性心脏表型是外周血单核细胞(PBMC)中发现的一种免疫刺激状态的结果，这种状态由氧/亚硝酸盐应激激活，并由PBMC(Mg2+)i缺乏诱导。其他人在WK3报道的饮食镁缺乏的心脏病理，同样发生在WKL的PBMC激活之前，并被抗氧化剂或P物质的受体拮抗剂(L-703,606)阻止。P物质是一种神经性炎症介质。我们检测了经Aldo/盐处理4周的大鼠的PBMC分子表型(MP)，包括所有表达的基因和蛋白。MRNA表达的变化揭示了早期(Wk1)ATPase依赖基因的减少和氧/亚硝化应激的逐渐发展，以及持续4周以上的抗氧化防御上调。B淋巴细胞反应，包括抗体基因的上调，从WKL开始出现。蛋白表达的变化证实了依赖于镁的钙泵和过氧化还蛋白-I的早期减少。因此，PBMC的转录组和蛋白质组可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生。具体目的：1)监测体内激活的PBMC中的MP，通过比较a)标准(Stan)或b)缺乏(Def)日粮中Aldo/盐加Mg2+的反应，或c)补充Stan周+Mg2+或d)单独补充Mg2+，来确定Aldo和Mg2+的作用；2)通过Spi、Nac或L-703,606的保护作用，监测体内激活的PBMC的MP，并确定与疾病和心脏病理相关的基因和蛋白；(3)确定诱导ALDO/SALT/STAN JOW所致的促炎性心脏表型所必需的外周血单核细胞类型(S)。这项研究可能确定预测CHF和心脏重塑发展的临床前标志物，并可能制定治疗策略。

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.