Reactive Inflammatory Species in Heart Failure

心力衰竭中的反应性炎症物质

• 批准号: 6687688
• 负责人: Pamela A Lucchesi
• 金额: $ 29万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-07-01 至 2004-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6687688
• 关键词: biochemistry; cardiac myocytes; disease /disorder model; echocardiography; electron spin resonance spectroscopy; enzyme activity; extracellular matrix; fibroblasts; free radical oxygen; genetically modified animals; heart failure; heart ventricle; hemodynamics; immunocytochemistry; intracardiac pressure; intracardiac volume; laboratory mouse; laboratory rat; metalloendopeptidases; microdialysis; myeloperoxidase; nitrogen compounds; oxidative stress; pathologic process; proteomics; superoxide dismutase; video microscopy

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.

描述（由申请人提供）：在具有体积过载的心脏中，复杂的补偿事件序列导致持续的额外细胞基质（ECM）重塑和肌细胞功能的变化，并最终导致充血性心力衰竭（HF）。越来越多的证据表明，统称为反应性炎症物种（RIS）的活性氧（ROS）和氮（RNS）物种，调节其生物利用度的酶与最终阶段HF模型中的收缩衰竭和心肌结构损害有关。但是，RI与HF的时间进展之间的关系尚未得到广泛的研究。使用大鼠的主动脉瘘（ACF）模型，3个密钥，临床上相关的时间点，体积超负荷时间的时间点在体内被严格定义：急性（2-5天），慢性补偿（4-8周），慢性补偿（4-8周）和慢性代偿分解（15-21周）。初步研究表明，在HF的急性相期间，肌丝蛋白的酪氨酸硝化增加，基质降解酶和信号分子。还观察到急性阶段以及在过渡到代偿性HF的过渡期间，还观察到了RIS产生酶与抗氧化剂防御能力之间的不平衡。此外，我们发现RI在孤立的成年心肌细胞中引起收缩功能障碍。这导致了以下假设：RI是不良LV重塑和收缩功能障碍的重要介体，这是体积超载引起的HF的发展和进展。 AIM 1将在反应性炎症物种与体积超载引起的CHF的发展和进展之间建立联系。将使用微透析，ESR（电子自旋共振）和标准生化测定的组合来测量RIS。一系列的药理干预措施和转基因方法（INOS（ - / - ），骨髓过氧化物酶（ - / - ），SOD过表达者将用于操纵体内RIS水平。一种蛋白质组学方法将用于鉴定RIS调节的蛋白质。 AIM 2将确定RIS在ACF诱导的HF中促进LV重塑的机制，尤其关注体内ECM转换和通过体外心脏成纤维细胞的调节基质金属蛋白酶（MMP）激活。 AIM 3将使用视频边缘显微镜，荧光Ca 2+成像和免疫细胞化学化学来确定在HF进展过程中对RIS的敏感性是否有助于心肌细胞。拟议的研究对于针对氧化剂诱导的损伤的治疗策略的发展至关重要，并且可能对HF的治疗具有重要意义。