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

基本信息

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
项目类别：
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

项目摘要

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.

项目概要心血管疾病，包括心力衰竭，是美国死亡的主要原因，新疗法需要更好地治疗这些疾病。心脏肥大是心脏变大的过程为了应对工作量的增加，尽管最初是适应性的，但这通常会导致心脏适应不良重塑并参与多种心脏病的发病机制。 Rac1，Rho家族小GTP酶，是心脏肥大发展所必需的，并在介导中发挥重要作用作为 NAPDH 氧化酶 2 (Nox2) 酶复合物的调节亚基，可调节心脏中的氧化应激。两个都肥厚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监管机制引起了制药行业的极大兴趣。拉克1是 Cys-178 处进行棕榈酰化，促进其激活和膜靶向。棕榈酰化是可逆的翻译后脂质修饰可动态调节蛋白质信号传导，并已被证明几种疾病状态下的病理信号传导所必需的。重要的是，遗传和小分子在临床前模型中，策略已被有效地用于靶向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里还没有经过考验。令人兴奋的是，我们的初步数据表明 Rac1 的基因抑制棕榈酰化可以保护新生大鼠心肌细胞（一种常见的体外心脏病模型）免受这两种疾病的侵害过度活跃的 Rac1 信号传导诱导的肥大和氧化应激。因此，我们假设 Rac1 在 Cys-178 处的棕榈酰化将 Rac1 靶向膜，在膜上它被激活并诱导致病性信号传导部分是通过调节 Nox2 复合物来实现的。该提案旨在确定 Rac1 的功能使用两种相关的心脏模型研究棕榈酰化在体内调节心脏肥大和氧化应激的作用肥大。我们将使用心脏肥大的慢性 AngII 输注模型以及使用 AAV- 的模型介导组成型活性 Rac1 的过度表达，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（C178S）的效果，丝氨酸不能严格棕榈酰化确定棕榈酰化对于心脏肥大和心肌氧化发展的必要性压力。这项工作的结果将首次测试棕榈酰化依赖性信号传导在调节心力衰竭的进展。该奖学金将为我提供成功所需的培训作为制药行业的独立科学家，并为我们共同的目标做出了重大贡献具有改善人类健康潜力的科学知识。