Targeting Lysosome Function in Lipid Overload Cardiomyopathy

脂质过载心肌病中的靶向溶酶体功能

• 批准号: 10621799
• 负责人: David Rawnsley
• 金额: $ 15.58万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-05-15 至 2027-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10621799
• 关键词: Acceleration; Address; Advisory Committees; Age; Animal Model; Area; Atherosclerosis; Attenuated; Autophagocytosis; Biogenesis; Biology; Cardiac; Cardiac Myocytes; Cardiology; Cardiomyopathies; Cardiovascular system; Cells; Ceramides; Cessation of life; Coenzyme A Ligases; Data; Development; Development Plans; Diabetes Mellitus; Disease; Doctor of Philosophy; Echocardiography; Environment; Enzymes; Epidemic; Etiology; Functional disorder; Gene Expression; Goals; Grant; Heart; Heart Diseases; Heart Injuries; Heart failure; High Fat Diet; Human; Hypertrophy; Immunoprecipitation; Impairment; Individual; Institution; Intermittent fasting; Intervention; Ischemia; Joints; Knowledge; Laboratories; Leadership; Left Ventricular Dysfunction; Lipids; Lysosomes; Mediating; Medicine; Mentors; Mentorship; Modeling; Molecular and Cellular Biology; Mus; Myocardial; Myocardial Ischemia; Myocardial dysfunction; Nuclear; Obesity; Outcome; Oxidative Stress Induction; Palmitates; Pathology; Pathway interactions; Patients; Phenotype; Physicians; Physiological; Population; Prevalence; Process; Proteins; Reperfusion Injury; Research; Research Personnel; Research Support; Risk; Risk Factors; Role; Scientist; Small Interfering RNA; Sphingolipids; Stress; System; Testing; Training; Transcriptional Activation; Transgenic Mice; Triglycerides; Up-Regulation; Wild Type Mouse; Writing; career; career development; clay; clinical training; diabetic cardiomyopathy; diet-induced obesity; dihydroceramide desaturase; epidemiology study; experimental study; heart function; improved; in vivo; knock-down; lipidomics; loss of function; mortality; mouse model; novel; overexpression; post-doctoral training; prevent; programs; protein aggregation; response to injury; skills; targeted treatment; therapy development; transcription factor; trend

Project Abstract The goals of this project are two-fold: 1) to evaluate the role of lysosomal dysfunction in lipotoxic cardiomyopathy and 2) to provide mentorship and training to allow the PI’s transition to independence. The prevalence of diabetes and obesity are increasing in the population, and both conditions are independent risk factors for the development of heart failure. Cardiac lipotoxicity has been identified as a potential pathway through which diabetes causes cardiomyopathy, but the understanding of how lipid overload disrupts cardiac function remains limited. Preliminary data acquired by the PI demonstrate that lipid overload-induced cardiac dysfunction is rescued by intermittent fasting. Intermittent fasting does not reduce cardiac triglyceride levels, but protein aggregate pathology is attenuated. Also, the levels of specific cardiac ceramide species are altered, suggesting that the effect of intermittent fasting is medicated by changing the level of individual lipid species, rather than overall reduction in lipids. Based on this data, this project hypothesizes that myocardial lipid overload impairs lysosome function via ceramide accumulation to induce cardiomyopathy and that stimulation of lysosomal biogenesis program by TFEB activation is sufficient to rescue this outcome. This hypothesis will be tested by assessing autophagic flux and lysosomal function in mice models of cardiac lipid overload and in cultured cardiomyocytes under lipid stress (Aim 1), examining cardiac lysosomal ceramide accumulation under lipid stress and the requirement for ceramide synthesis in cardiac lipotoxicity (Aim 2), and evaluating the role of TFEB in stimulating lysosomal biogenesis to improve lipotoxic cardiomyopathy (Aim 3). Completion of these aims will address knowledge gaps in the field of cardiac lipotoxicity and also provide training to facilitate the career development of the PI. The PI has previously obtained PhD training in molecular and cellular biology and has undertaken postdoctoral training in the lab of Dr. Abhinav Diwan, following completion of clinical training in medicine and cardiology. The PI seeks additional scientific training in a mentored setting to address the knowledge gaps described. Specifically, the proposed career development plan will provide additional training in 4 areas: 1) autophagy and lysosomal biology, 2) lipid biology and lipidomics, with a focus on sphingolipid biology, 3) echocardiographic analysis of animal models of cardiac disease, and 4) training in grant writing, presentation skills, and leadership. This plan will be guided by mentorship and research support from Dr. Abhinav Diwan and Dr. Douglas Mann, experts in lysosomal biology and myocardial biology, respectively, as well as by additional mentorship from the advisory committee with renowned expertise in lysosomal biology (Dr. Stuart Kornfeld), lipid biology (Dr. Brian Finck and Dr. Clay Semenkovich), and sphingolipid biology and lipidomics (Dr. Ashley Cowart). This training and mentorship in a highly supportive institutional training environment will enable the PI to develop into an independent cardiovascular investigator and physician-scientist focused on studying the role of lysosomes in cardiovascular development and in the myocardial response to injury.

项目摘要 该项目的目标有两个折：1）评估溶酶体功能障碍在脂肪毒性心肌病中的作用 2）提供精通和培训，以使PI过渡到独立。糖尿病的患病率 人口的肥胖症正在增加，这两种情况都是独立的风险因素 心力衰竭的发展。心脏脂肪毒性已被确定为潜在途径 糖尿病会引起心肌病，但对脂质超负荷如何破坏心脏功能的理解仍然存在 有限的。 PI获得的初步数据表明，脂质超载引起的心脏功能障碍是 由间歇性禁食救出。间歇性禁食不会降低心脏甘油三酸酯水平，而是蛋白质 骨料病理学衰减。同样，改变了特定心脏神经酰胺物种的水平，表明 通过改变单个脂质物种的水平，而不是 脂质的总体减少。基于此数据，该项目假设心肌脂质过载损害 通过神经酰胺积累来诱导心肌病和溶酶体的溶酶体功能 TFEB激活的生物发生程序足以挽救这一结果。该假设将通过 评估心脏脂质过载的小鼠模型和培养的小鼠模型中的自噬通量和溶酶体功能 脂质胁迫下的心肌细胞（AIM 1），检查脂质下心脏溶酶体神经酰胺的积累 压力和对心脏脂肪毒性中神经酰胺合成的需求（AIM 2），并评估TFEB的作用 刺激溶酶体生物发生以改善脂肪毒性心肌病（AIM 3）。这些目标的完成将 解决心脏脂肪毒性领域的知识差距，还提供培训以促进职业 PI的开发。 PI先前已经获得了分子和细胞生物学的博士学位培训，并且具有 在完成临床培训后，在Abhinav Diwan博士的实验室进行博士后培训 医学和心脏病学。 PI在指导环境中寻求其他科学培训，以解决 所描述的知识差距。具体而言，拟议的职业发展计划将提供额外的培训 在4个领域：1）自噬和溶酶体生物学，2）脂质生物学和脂质组学，重点是鞘脂 生物学，3）心脏病动物模型的超声心动图分析，4）授予写作培训， 演讲技巧和领导能力。该计划将由Abhinav博士的指导和研究支持指导 Diwan和Douglas Mann博士，分别是溶酶体生物学和心肌生物学专家，以及 咨询委员会的额外精神统治，并拥有著名的溶酶体生物学专业知识（Stuart博士 Kornfeld），脂质生物学（Brian Finck博士和Clay Semenkovich博士），以及鞘脂生物学和脂质组学（博士 阿什利·考特（Ashley Cowart））。在高度支持的机构培训环境中的这种培训和心态将使 PI发展成独立的心血管研究者和身体科学家，专注于研究 溶酶体在心血管发育以及对损伤的心肌反应中的作用。