Reactive Inflammatory Species in Heart Failure

描述（由申请人提供）：在容量过载的心脏中，一系列复杂的代偿事件导致细胞外基质（ECM）重构的持续状态和心肌细胞功能的改变，最终导致充血性心力衰竭（HF）。越来越多的证据表明，活性氧（ROS）和活性氮（RNS）物种，统称为反应性炎症物种（RIS），以及调节其生物利用度的酶与终末期HF模型的收缩衰竭和心肌结构损伤有关。然而，RIS与HF时间进展之间的关系尚未得到广泛研究。使用大鼠主动脉腔瘘（ACF）模型，在体内严格定义了容量过载时间进展的3个关键临床相关时间点：急性（2-5天），慢性代偿（4-8周）和慢性代偿失代偿（15-21周）。初步研究表明，心衰急性期肌丝蛋白、基质降解酶和信号分子的酪氨酸硝化作用增加。在急性期和向失代偿性心衰过渡期间，也观察到RIS生成酶和抗氧化防御之间的不平衡。此外，我们发现RIS可引起离体成人心肌细胞的收缩功能障碍。这导致了RIS是不利的左室重构和收缩功能障碍的重要介质的假设，这是容量过载引起的心衰的发生和发展的基础。目的1将建立反应性炎症物种与容量超载诱导的CHF的发生和进展之间的联系。RIS将使用微透析，ESR（电子自旋共振）和标准生化分析的组合来测量。一系列的药物干预和转基因方法(iNOS（-/-)，髓过氧化物酶（-/-），SOD过表达物）将被用来操纵体内的RIS水平。蛋白质组学方法将用于鉴定ris调节的蛋白质。目的2将确定RIS在acf诱导的HF中促进左室重塑的机制，特别关注体内ECM的转换和体外心脏成纤维细胞对基质金属蛋白酶（MMP）激活的调节。目的3将使用视频边缘显微镜、荧光ca2 +成像和免疫细胞化学来确定HF进展过程中对RIS易感性的改变是否有助于心肌细胞。所提出的研究对于针对氧化性损伤的治疗策略的发展至关重要，并且可能对心衰的治疗具有重要意义。

DESCRIPTION (provided by applicant): In hearts with volume overload, a complex sequence of compensatory events result in a continual state of extra cellular matrix (ECM) remodeling and by changes in myocyte function and eventually leads to congestive heart failure (HF). Increasing evidence suggests that reactive oxygen (ROS) and nitrogen (RNS) species, collectively termed reactive inflammatory species (RIS), and the enzymes that regulate their bioavailability are associated with contractile failure and myocardial structural damage in end-stage HF models. However, the relationship between RIS and the temporal progression of HF has not been extensively studied. Using an aortocaval fistula (ACF) model in the rat, 3 key, clinically relevant, time points in the temporal progression of volume overload have been rigorously defined in vivo: acute (2-5 days), chronic compensated (4-8 weeks), and chronic decompensated (15-21 weeks). Preliminary studies indicate increased tyrosine nitration of myofilament proteins, matrix degrading enzymes and signaling molecules during the acute phase of HF. An imbalance between RIS generating enzymes and antioxidant defenses was also observed acute stage and during the transition to decompensated HF. Moreover, we have found that RIS cause contractile dysfunction in isolated adult cardiac myocytes. This led to the hypothesis that RIS are important mediators of adverse LV remodeling and contractile dysfunction that underlie the development and progression of volume overload-induced HF. Aim 1 will establish a link between reactive inflammatory species and the development and progression of volume overload-induced CHF. RIS will be measured using a combination of microdialysis, ESR (electron spin resonance) and standard biochemical assays. A series of pharmacological interventions and transgenic approaches (iNOS(-/-), myeloperoxidase (-/-), SOD overexpressors) will be used to manipulate RIS levels in vivo. A proteomics approach will used to identify RIS-modulated proteins. Aim 2 will determine the mechanisms by which RIS contribute to LV remodeling in ACF-induced HF, with particular focus on ECM turnover in vivo and the regulation matrix metalloproteinase (MMP) activation by cardiac fibroblasts in vitro. Aim 3 will use video edge microscopy, fluorescent Ca 2+ imaging and immunocytochemistry to determine whether altered susceptibility to RIS during HF progression contributes to cardiomyocyte. The proposed investigations are fundamentally important to the development of therapeutic strategies targeted to oxidant-induced injury and may have important implications in the treatment of HF.