Caveolin-3 and cardiac fibrosis

Caveolin-3 和心脏纤维化

• 批准号: 9318093
• 负责人: PAUL A INSEL
• 金额: $ 23.25万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-04-01 至 2019-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9318093
• 关键词: Address; Adult; Age; Aging; Agonist; American; Angiotensin II; Animals; Brain; Cardiac; Cardiac Myocytes; Cardiac Output; Cardiovascular Diseases; Cardiovascular system; Cause of Death; Caveolae; Caveolins; Cells; Clinical; Collagen; Collagen Type I; Complication; Coupling; Data; Development; Disease; EFRAC; Elderly; Endothelin-1; Engineering; Extracellular Matrix; Extracellular Matrix Degradation; Failure; Fibroblasts; Fibrosis; Functional disorder; Goals; Heart; Heart Diseases; Heart failure; Injury; Kidney; Knock-out; Knockout Mice; Mechanical Stimulation; Mediating; Mediator of activation protein; Mission; Morbidity - disease rate; Mus; Myocardial dysfunction; Myofibroblast; Perfusion; Phenotype; Physiological; Plasminogen Activator Inhibitor 1; Production; Property; Proteins; Proteomics; Relaxation; Research; Smooth Muscle Actin Staining Method; Stimulus; Structure; Testing; Therapeutic; Tissues; Transforming Growth Factor beta; Transforming Growth Factors; Viral; Virus; Wild Type Mouse; age related; aged; aging population; base; caveolin-3; constriction; coronary fibrosis; cytokine; disability; effective therapy; exercise capacity; exosome; gene therapy; healthy aging; high reward; high risk; improved; innovation; insight; mortality; novel; overexpression; response; response to injury; restoration; transcriptome sequencing

Project Summary/Abstract Cardiovascular disease is the major cause of death in Americans over the age of 65. Mechanisms of cardiovascular aging are not well defined nor are effective treatments available. This project proposes a novel hypothesis: age-related loss in the expression by cardiac myocytes of caveolae and the protein caveolin-3 with the resultant stimulation of pro-fibrotic activity of cardiac fibroblasts, thereby enhancing production of extracellular matrix, cardiac fibrosis, diastolic dysfunction, and heart failure, especially heart failure with preserved ejection fraction (HFpEF). HFpEF is a clinical problem for which no effective therapies exist. This hypothesis derives from our preliminary data which show that cardiac myocytes of aged mice have a loss in expression of caveolae and their key resident protein, caveolin-3 and that cardiac fibroblasts isolated from aged animals have increased pro- fibrotic activity, which we detect in fibroblasts cultured ex vivo. Our proposed studies will test if caveolin-3 in cardiac myocytes has cardioprotective properties in aging by reducing the profibrotic state of cardiac fibroblasts, thus blunting the development and progression of aging-related cardiac fibrosis. In addition, we will determine if restoration of the loss in caveolin-3 with advanced age can reduce age-related cardiac fibrosis. Our two specific aims will ask: 1) Does caveolin-3 expression in cardiac myocytes regulate the pro-fibrotic state of cardiac fibroblasts and cardiac fibrosis in aging? and 2) Does restoration of caveolin-3 in cardiac myocytes reduce age- related cardiac fibrosis? In Aim 1, we will assess cardiac function and the fibrotic activity of cardiac fibroblasts isolated from young (2-3 month) and aged (18-22 month) wild-type, caveolin-3- knockout, and cardiac myocyte- targeted caveolin-3 over-expressing mice. We will also conduct RNA-seq studies of cardiac myocytes and cardiac fibroblasts and will use conditioned media from cardiac myocytes to assess exosomes and soluble proteins released into the media by young and old hearts. In addition to studies of physiological aging, we will subject mice to transaortic constriction, which induces cardiac fibrosis, so as to increase the dynamic range of fibrotic changes. In Aim 2, we will test the impact of AAV constructs engineered to increase caveolin-3 expression in cardiac myocytes on cardiac function, cardiac myocytes and cardiac fibroblasts using the approaches from Aim 1. Based on our preliminary data and past efforts, the proposed studies should be highly feasible even though they are of the high risk/high reward type that is sought in R21 applications. We believe that the results will advance understanding of aging-related cardiac fibrosis and dysfunction and may identify a therapeutic approach—increasing caveolin-3 expression in the heart—for a major contributor to morbidity and mortality in the aged population.

项目概要/摘要 心血管疾病是 65 岁以上美国人死亡的主要原因。 心血管衰老尚无明确定义，也没有有效的治疗方法。该项目提出了一种新颖的 假设：与年龄相关的心肌细胞小窝和小窝蛋白 3 表达的丧失 由此刺激心脏成纤维细胞的促纤维化活性，从而增强细胞外细胞的产生 基质、心脏纤维化、舒张功能障碍和心力衰竭，尤其是射血保留的心力衰竭 分数（HFpEF）。 HFpEF 是一个尚无有效治疗方法的临床问题。这个假设源自 我们的初步数据表明，老年小鼠的心肌细胞小窝表达丧失，并且 他们的关键驻留蛋白 Caveolin-3 以及从老年动物中分离出的心脏成纤维细胞增加了亲 我们在离体培养的成纤维细胞中检测到纤维化活性。我们提出的研究将测试 Caveolin-3 是否在 心肌细胞通过减少心脏成纤维细胞的促纤维化状态，在衰老过程中具有心脏保护特性， 从而减缓与衰老相关的心脏纤维化的发生和进展。此外，我们将确定是否 随着年龄的增长，恢复caveolin-3的缺失可以减少与年龄相关的心脏纤维化。我们的两个具体 目标会问：1）心肌细胞中的caveolin-3表达是否调节心脏的促纤维化状态？ 成纤维细胞和衰老过程中的心脏纤维化？ 2) 心肌细胞中的 Caveolin-3 恢复是否会降低年龄？ 与心脏纤维化有关？在目标 1 中，我们将评估心脏功能和心脏成纤维细胞的纤维化活性 从幼年（2-3 个月）和老年（18-22 个月）野生型、caveolin-3- 敲除和心肌细胞中分离 靶向 Caveolin-3 过度表达小鼠。我们还将开展心肌细胞的 RNA-seq 研究 心脏成纤维细胞，并将使用心肌细胞的条件培养基来评估外泌体和可溶性 年轻和年老的心脏释放到介质中的蛋白质。除了生理衰老的研究之外，我们还将 对小鼠进行经主动脉收缩，诱导心脏纤维化，从而增加心脏的动态范围 纤维化改变。在目标 2 中，我们将测试旨在增加 Caveolin-3 表达的 AAV 构建体的影响 使用以下方法在心肌细胞中对心脏功能、心肌细胞和心脏成纤维细胞产生影响 目标 1. 根据我们的初步数据和过去的努力，所提出的研究即使在 尽管它们属于 R21 应用程序所寻求的高风险/高回报类型。我们相信结果 将增进对与衰老相关的心脏纤维化和功能障碍的了解，并可能确定治疗方法 方法——增加心脏中的caveolin-3表达——是导致发病率和死亡率的主要因素 老年人口。