Investigating the novel role of acetylation in cardiac mitochondrial bioenergetics and function in the aging heart

研究乙酰化在心脏线粒体生物能学和衰老心脏功能中的新作用

• 批准号: 9890081
• 负责人: Dharendra Thapa
• 金额: $ 17.3万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-01-08 至 2021-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9890081
• 关键词: Acetylation; Acetyltransferase; Address; Age; Aging; Animal Model; Animals; Bioenergetics; Biological Assay; Biological Process; Biology; Cardiac; Cardiac Myocytes; Coenzyme A; Coupled; Data; Deacetylase; Development; Development Plans; Diet; Disease; Energy Metabolism; Energy Supply; Environment; Enzymes; Functional disorder; Future; Generations; Genetic; Goals; Heart; Human; In Vitro; Knowledge; Lead; Long-Chain-Acyl-CoA Dehydrogenase; Lysine; Mass Spectrum Analysis; Mediating; Mentorship; Metabolic; Mitochondria; Modeling; Molecular; Mus; Myocardial dysfunction; Obese Mice; Obesity; Oxidoreductase; Pathogenesis; Peptides; Population Growth; Post-Translational Protein Processing; Process; Protein Acetylation; Proteins; Proteomics; Regulation; Research; Research Personnel; Research Proposals; Resolution; Resources; Role; Site; Stress; System; Testing; Tissues; Universities; Work; age related; aged; aging population; base; biochemical tools; career development; economic impact; enzyme activity; enzyme substrate; fatty acid oxidation; flexibility; health economics; healthy aging; heart function; improved; in vivo; insight; long chain fatty acid; middle age; mitochondrial dysfunction; mitochondrial metabolism; new therapeutic target; novel; novel therapeutics; oxidation; prevent; research study; therapy outcome; training opportunity

Cardiac mitochondrial dysfunction is central to the pathogenesis of aging and many age related diseases. Mitochondria supply the bioenergetic capacity for cardiac contractile function through oxidation of fuel substrates and a complete control of this system is indispensable to maintain cardiac efficiency. Specifically, the role of Hydroxyacyl-CoA Dehydrogenase (HADHA) and Long Chain Acyl-CoA Dehydrogenase (LCAD) in catalyzing the oxidation of long chain fatty acids in the heart is well studied and their dysfunction is associated with decreased fatty acid oxidation (FAO) and cardiac energy depletion. However, studies focused on understanding the cellular mechanisms that regulate these key mitochondrial energy substrate enzymes in the aging heart are scarce. In a recent study, we described that increased acetylation increases the activities of LCAD and HADHA in diet induced obesity, which was mediated by changes in the expression of mitochondrial acetyltransferase GCN5L1 and deacetylase SIRT3. In the aging heart, we observe increased GCN5L1 and decreased SIRT3 expression resulting in an increased acetylation status of HADHA and LCAD. Based on these observations, we hypothesize that GCN5L1 and SIRT3 control HADHA and LCAD acetylation, and that dysregulation of this mechanism in aging contributes to reduced mitochondrial bioenergetics and cardiomyocyte energy depletion. To test our central hypothesis, we propose the following aims: 1. We will investigate how acetylation regulates the activity of HADHA and LCAD in young, middle aged and old mouse hearts. Using high resolution mass spectrometry based proteomics; we will identify acetylation sites, relative quantification and assess their impact in key biological processes and enzymatic functions. 2. We will investigate the mechanisms associated with regulation of HADHA and LCAD activity in young, middle aged and old mouse hearts. We will use novel GCN5L1 and SIRT3 cardiac KO animal to delineate the molecular mechanisms underlying changes in HADHA and LCAD acetylation in aging process. 3. We will investigate how changes in fatty acid oxidation protein acetylation impacts mitochondrial bioenergetics and cardiac contractile function in aging heart. The long term goal of this study is to understand the regulatory role of cardiac mitochondrial acetylation in human aging and age related diseases. Our results will improve our understanding of acetylation mediated regulation of FAO enzymes in aging mitochondrial biology and provide novel insights on regulation of fuel substrate usage in the aging heart and their contribution towards improving mitochondrial and cardiac function with age.

心脏线粒体功能障碍是衰老和许多与年龄相关的疾病发病机制的核心。 线粒体通过燃料氧化提供心脏收缩功能的生物能能力 底物和对该系统的完全控制对于维持心脏效率是必不可少的。具体来说， 羟酰辅酶 A 脱氢酶 (HADHA) 和长链酰辅酶 A 脱氢酶 (LCAD) 在 催化心脏中长链脂肪酸的氧化已得到充分研究，其功能障碍与其相关 脂肪酸氧化（FAO）减少和心脏能量消耗。然而，研究的重点是 了解调节这些关键线粒体能量底物酶的细胞机制 衰老的心脏稀缺。在最近的一项研究中，我们描述了乙酰化的增加会增加 饮食中的 LCAD 和 HADHA 诱导肥胖，这是由线粒体表达变化介导的 乙酰转移酶 GCN5L1 和脱乙酰酶 SIRT3。在衰老的心脏中，我们观察到 GCN5L1 和 SIRT3 表达减少导致 HADHA 和 LCAD 乙酰化状态增加。基于 根据这些观察结果，我们假设 GCN5L1 和 SIRT3 控制 HADHA 和 LCAD 乙酰化，并且 衰老过程中这种机制的失调会导致线粒体生物能降低， 心肌细胞能量耗尽。为了检验我们的中心假设，我们提出以下目标： 1. 我们将 探讨乙酰化如何调节幼、中、老年小鼠HADHA和LCAD活性 心。使用基于蛋白质组学的高分辨率质谱；我们将确定乙酰化位点，相对 量化并评估它们对关键生物过程和酶功能的影响。 2. 我们会 探讨中青年HADHA和LCAD活性调节的相关机制 和老老鼠的心。我们将使用新型 GCN5L1 和 SIRT3 心脏 KO 动物来描绘分子 衰老过程中 HADHA 和 LCAD 乙酰化变化的潜在机制。 3. 我们将研究如何 脂肪酸氧化蛋白乙酰化的变化影响线粒体生物能和心脏收缩 老化心脏的功能。本研究的长期目标是了解心脏的调节作用 人类衰老和年龄相关疾病中的线粒体乙酰化。我们的结果将增进我们的理解 乙酰化介导的FAO酶在衰老线粒体生物学中的调节，并提供新的见解 关于衰老心脏中燃料底物使用的调节及其对改善线粒体的贡献 和心脏功能随年龄的变化。