Determining the role of Rac1 palmitoylation in cardiac hypertrophy and oxidative stress

确定 Rac1 棕榈酰化在心脏肥大和氧化应激中的作用

• 批准号: 10534386
• 负责人: James Patrick Teuber
• 金额: $ 3.91万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-01-01 至 2025-12-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10534386
• 关键词: Address; Angiotensin II; Cardiac; Cardiac Myocytes; Cardiac development; Cardiomyopathies; Cardiovascular Diseases; Cause of Death; Cell Size; Cell membrane; Chronic; Complex; Cysteine; Data; Dependovirus; Dilated Cardiomyopathy; Disease; Disease model; Drug Industry; Echocardiography; Family; Fatty Acids; Fellowship; Functional disorder; Gene Expression; Genetic; Golgi Apparatus; Growth; Health; Heart; Heart Diseases; Heart Hypertrophy; Heart failure; Human; Hyperactivity; Hypertension; Hypertrophy; In Vitro; Inflammation; Inflammatory; Infusion procedures; Knock-out; Knowledge; Lipids; Malignant Neoplasms; Measures; Mediating; Membrane; Modeling; Modification; Monomeric GTP-Binding Proteins; Multienzyme Complexes; Mus; Mutate; Mutation; Myocardial; Neonatal; Nodal; Oxidases; Oxidation-Reduction; Oxidative Stress; Pathogenesis; Pathogenicity; Pathologic; Play; Pre-Clinical Model; Process; Production; Proteins; Public Health; Pump; Rattus; Reactive Oxygen Species; Regulation; Research Personnel; Role; Saline; Scientist; Serine; Signal Transduction; Signaling Protein; Stimulus; Testing; Time; Training; Transgenic Mice; United States; Weight; Work; Workload; genetic approach; improved; in vitro Model; in vivo; interest; mortality; mutant; novel; novel therapeutics; overexpression; palmitoylation; pre-clinical; response; rho; skills; small molecule; spatiotemporal; stem; targeted treatment

PROJECT SUMMARY Cardiovascular disease, including heart failure, is the leading cause of mortality in the USA and new therapeutics are needed to better treat these diseases. Cardiac hypertrophy is the process by which the heart becomes larger in response to an increased workload and although initially adaptive, this often leads to maladaptive cardiac remodeling and is involved in the pathogenesis of several cardiac diseases. Rac1, a Rho family small GTPase, is required for the development of cardiac hypertrophy and relatedly plays an important role in mediating oxidative stress in the heart as a regulatory subunit of the NAPDH oxidase 2 (Nox2) enzyme complex. Both hypertrophy and oxidative stress promote the progression of heart failure and therefore determining novel regulatory mechanisms controlling these processes is of great interest to the pharmaceutical industry. Rac1 is palmitoylated at Cys-178 which promotes its activation and membrane targeting. Palmitoylation is a reversible post-translational lipid modification that dynamically regulates protein signaling and has been shown to be required for pathologic signaling in several disease states. Importantly, both genetic and small molecule strategies have been effectively utilized to target palmitoylation of specific proteins in pre-clinical models of diseases such as cancer and inflammation. However, the role of palmitoylation in regulating pathologic signaling in the heart remains untested. Excitingly, our preliminary data demonstrate that genetic inhibition of Rac1 palmitoylation protects neonatal rat cardiomyocytes, a common in vitro model of cardiac disease, from both hypertrophy and oxidative stress induced by hyperactive Rac1 signaling. Therefore, we hypothesize that palmitoylation of Rac1 at Cys-178 targets Rac1 to the membrane where it is activated and induces pathogenic signaling in part through regulation of the Nox2 complex. This proposal seeks to determine the function of Rac1 palmitoylation in regulating cardiac hypertrophy and oxidative stress in vivo using two relevant models of cardiac hypertrophy. We will use a chronic AngII infusion model of cardiac hypertrophy as well as a model using AAV- mediated overexpression of constitutively active Rac1, which causes dilated cardiomyopathy. In these models, we will test the effect of mutating Cys-178 to serine (C178S) which cannot be palmitoylated to rigorously determine the necessity of palmitoylation for the development of cardiac hypertrophy and myocardial oxidative stress. The results of this work will test, for the first time, a role for palmitoylation-dependent signaling in regulating the progression to heart failure. This fellowship will provide me with the training necessary to succeed as an independent scientist in the pharmaceutical industry as well as make significant contributions to our shared scientific knowledge that have the potential to improve human health.

项目摘要 心血管疾病，包括心力衰竭，是美国死亡的主要原因， 来更好地治疗这些疾病。心脏肥大是心脏变大的过程 响应于增加的工作负荷，尽管最初是适应性的，但这常常导致适应不良的心脏病。 它参与了心脏重塑，并参与了几种心脏疾病的发病机制。Rac 1，Rho家族小GT3， 是心肌肥厚发展所必需的，并且在介导 作为NAPDH氧化酶2（Nox 2）酶复合物的调节亚基，在心脏中的氧化应激。两 肥大和氧化应激促进心力衰竭的进展，因此确定新的 控制这些过程的调节机制是制药工业非常感兴趣的。Rac 1是 在Cys-178处棕榈酰化，其促进其活化和膜靶向。棕榈酰化是可逆的 动态调节蛋白质信号传导的翻译后脂质修饰， 在几种疾病状态下的病理信号所需的。重要的是，遗传和小分子 已经有效地利用了一些策略来靶向临床前模型中特定蛋白质的棕榈酰化， 癌症和炎症等疾病。然而，棕榈酰化在调节病理信号传导中的作用 心脏中的残留物还没有检测出来令人兴奋的是，我们的初步数据表明，Rac 1的遗传抑制 棕榈酰化保护新生大鼠心肌细胞，一种常见的心脏病体外模型， 肥大和氧化应激诱导的过度活跃的Rac 1信号。因此，我们假设 Rac 1在Cys-178处的棕榈酰化将Rac 1靶向至膜，在膜中Rac 1被激活并诱导致病性 部分通过调节Nox 2复合物进行信号传导。本建议旨在确定Rac 1的职能 棕榈酰化在体内调节心肌肥大和氧化应激中的作用 肥厚我们将使用心脏肥大的慢性AngII输注模型以及使用AAV的模型。 介导的组成型活性Rac 1过表达，导致扩张型心肌病。在这些模型中， 我们将测试将Cys-178突变为丝氨酸（C178 S）的效果，所述丝氨酸不能被棕榈酰化以严格地 确定棕榈酰化对心肌肥大和心肌氧化损伤的发展的必要性 应力这项工作的结果将首次测试棕榈酰化依赖性信号在 调节心力衰竭的进程这个奖学金将为我提供成功所必需的培训 作为制药行业的独立科学家，为我们共同的事业做出了重大贡献。 有潜力改善人类健康的科学知识。