Translational investigation of abnormal fat metabolism in mitochondrial disease

线粒体疾病中脂肪代谢异常的转化研究

• 批准号: 8890499
• 负责人: SHANA ERIN MCCORMACK
• 金额: $ 17.21万
• 依托单位: CHILDREN'S HOSP OF PHILADELPHIA
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-07-01 至 2018-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8890499
• 关键词: Acids; Adolescent; Adult; Antimycin A; Area; Award; Carbohydrates; Cell Line; Cell Respiration; Cell model; Cells; Cellular Metabolic Process; Child; Childhood; Citrates; Citric Acid Cycle; Clinical; Collaborations; Complement; Complex; Diabetes Mellitus; Diet; Disease; Dyslipidemias; Electron Transport Complex III; Endocrine; Endocrine System Diseases; Endocrinology; Energy-Generating Resources; Equilibrium; Etiology; Euglycemic Clamping; Faculty; Fatty Acids; Fatty acid glycerol esters; Functional disorder; Funding; Future; Genetic; Glucose; Glucose Clamp; Glutamine; Goals; Health; HepG2; High Density Lipoprotein Cholesterol; High Density Lipoproteins; Human; Human Cell Line; Hypertriglyceridemia; Imaging technology; Impairment; In Vitro; Incidence; Individual; Insulin; Insulin Resistance; Investigation; Journals; Knowledge; Lead; Learning; Lipids; Lipolysis; Liver; Magnetic Resonance Imaging; Magnetic Resonance Spectroscopy; Mass Spectrum Analysis; Medicine; Mentored Patient-Oriented Research Career Development Award; Mentors; Metabolic; Metabolic Diseases; Metabolic Pathway; Metabolism; Methodology; Mitochondria; Mitochondrial DNA; Mitochondrial Diseases; Modeling; Muscle; Mutation; NADH; Nicotinamide adenine dinucleotide; Non-Insulin-Dependent Diabetes Mellitus; Nuclear; Nutrient; Obesity; Oxidation-Reduction; Pathogenesis; Pathway interactions; Patients; Peer Review; Performance; Phenotype; Physicians; Physiological; Plasma; Population; Proteins; Public Health; Publishing; Relative (related person); Reporting; Research; Research Infrastructure; Research Personnel; Resources; Respiratory Chain; Rhabdomyosarcoma; Risk; Role; Rotenone; Scientist; Secure; Skeletal Muscle; Solid; Source; Techniques; Testing; Therapeutic Intervention; Tissues; Tracer; Training; Training and Infrastructure; Triglycerides; Work; alpha ketoglutarate; base; career; career development; clinical care; cohort; design; diagnosis evaluation; energy balance; epigenomics; fatty acid oxidation; genetic disorder diagnosis; glucose production; glucose uptake; healthy volunteer; hepatoma cell; improved; in vivo; inhibitor/antagonist; insight; insulin sensitivity; lipid biosynthesis; lipid metabolism; meetings; member; mitochondrial DNA mutation; mitochondrial dysfunction; non-diabetic; novel; nutrition; obesity in children; oxidation; patient oriented research; research study; response; skills; spectroscopic imaging; stable isotope; treatment strategy; tumor

 DESCRIPTION (provided by applicant): Pediatric obesity is an increasingly prevalent public health crisis that contributes to the rising global burden of type 2 diabetes. Obesity and diabetes, at the most fundamental level, represent disorders of energy balance. In obesity, energy storage exceeds utilization. In diabetes, available energy sources (glucose) are improperly used. Energy balance is sensed and controlled by the cell's mitochondria. Focused study of key mitochondrial pathways that are disrupted in disorders of energy balance will improve our understanding of endocrine complications of obesity, and may lead to new treatment approaches. A particularly relevant group to study to better understand the intersection of mitochondrial dysfunction and obesity-related endocrine disorders are patients with primary (genetic) mitochondrial diseases, who develop similar profiles of disordered fat metabolism even in the absence of overt diabetes or obesity, including hypertriglyceridemia and low high density lipoprotein (HDL) cholesterol. Through the proposed K23 Mentored Patient-Oriented Research Career Development Award, I will investigate the mechanistic basis and metabolic consequences of disrupted lipid metabolism in primary mitochondrial disease. The proposed studies will directly support my main career goals as I progress towards independence as a physician-scientist. These goals are to [1] advance our understanding of the role of mitochondria, energy balance, and metabolism in pediatric endocrine disease, and to [2] apply physiologic insights to develop rational, targeted, and effective therapeutic interventions to improve the health of patients with endocrine and metabolic diseases. These goals will be advanced during the K23 award period through the pursuit of 3 overarching training and career development objectives: First, I will acquire didactic and technical knowledge critical for the successful design and execution of patient-oriented research in this area. During the three years of the proposed award, I will learn to perform valuable in vitro and in vivo phenotyping techniques under the guidance of content-area expert advisors. Specifically, in vitro utilization of stable isotopes and manipulation of "cybrid" cell lnes, and in vivo performance of hyperinsulinemic-euglycemic clamp studies complemented by stable isotope studies will be invaluable skills. Second, I will accrue new expertise in the diagnosis, evaluation, and management of patients with primary mitochondrial disease. This population has a large, unmet clinical need for better-informed subspecialists in all areas, particularly including Pediatric Endocrinology. They further provide a focused opportunity to study the role of the mitochondrial dysfunction in common endocrine disorders. This goal will be met by providing clinical care for mitochondrial disease patients and performing both in vitro and in vivo research investigations to characterize the extent and basis of their dyslipidemia. Third, I will transition to independence as an investigator. I will continue to work and develop productive multi-disciplinary collaborations with the expert members of my mentoring committee. I will gain necessary expertise to transition to independence through completing of the proposed studies, presenting at national meetings, publishing in peer-reviewed journals, and securing subsequent R01 funding.. Performing this proposed project will help accomplish these goals. These experiments will test our central hypotheses that: [1] altered cellular NAD+/NADH redox balance in the setting of primary respiratory chain (RC) impairment leads to increased de novo lipid synthesis from alpha-ketoglutarate (αKG)- derived citrate and decreased fatty acid oxidation (FAO) capacity and [2] the resulting excess accumulation of lipids in skeletal muscle causes skeletal muscle insulin resistance. To test these hypotheses, we will employ both in vitro and in vivo approaches. We will use in vitro human cell line models to test whether RC inhibition quantifiably increases de novo lipogenesis via "reversed" citric acid cycle flow. A complementary in vivo approach will look for evidence of increased de novo lipogenesis, muscle lipid accumulation, and decreased insulin sensitivity in (i) adults with primary RC disease, with hypertriglyceridemia but without DM. We will compare this group to (ii) appropriately matched healthy individuals. To assess whether "reversed" citric acid cycle flux might also contribute to hypertriglyceridemia in "typical" non-diabetic obese individuals, we will also study (iii) appropriately matched obese individuals. In future, we can extend aspects of these studies to the pediatric population. This project leverages many unique resources at CHOP and Penn. First, my primary mentor, Dr. Marni J. Falk, has a large and well-phenotyped cohort of patients with clear genetic diagnoses of mitochondrial disease that provides a ready source of ideal subjects, and tissues, in which to perform the proposed studies. CHOP's Center for Mitochondrial and Epigenomic Medicine (CMEM) further offers world-class infrastructure in this field. Penn's Diabetes Research Center (DRC) has faculty and core expertise already in place to assure successful completion of detailed metabolic phenotyping studies, where key faculty are comentors. Our collaborators at Penn's Center for Advanced Magnetic Resonance Imaging and Spectroscopy (CAMRIS) have developed metabolic imaging technologies to estimate and localize mitochondrial function. This work will allow me to establish a solid background from which to pursue future, independently-funded studies on the role of mitochondria, energy balance, and metabolism in pediatric endocrine disease

 描述（由申请人提供）： 小儿肥胖是日益普遍的公共卫生危机，导致2型糖尿病的全球燃烧症有所上升。在最基本的水平上，肥胖和糖尿病代表了能量平衡的疾病。在肥胖症中，储能超过了利用。在糖尿病中，不当使用可用的能源（葡萄糖）。能量平衡是由细胞的线粒体传感和控制的。对能量平衡疾病残疾的关键线粒体途径的重点研究将改善我们对肥胖内分泌并发症的理解，并可能导致新的治疗方法。一个特别相关的研究小组，以更好地了解线粒体功能障碍和与肥胖相关的内分泌疾病的相互作用是主要（遗传）线粒体疾病的患者，即即使在超过肥胖的糖尿病或肥胖症的情况下，包括超级糖尿病和高度trolligliglyceridemia and low low diplyserty lipecote and liplip liplip liply（HH dl dipligity lip lipligity and cartery fat fat fat fat脂肪代谢也存在相似的特征。通过拟议的K23指导的以患者为导向的研究职业发展奖，我将研究原发性线粒体疾病中脂质代谢中断的机械基础和代谢后果。拟议的研究将直接支持我作为身体科学家独立的主要职业目标。这些目标是[1]促进我们对线粒体，能量平衡和代谢在小儿内分泌疾病中的作用的理解，并[2]应用生理见解来开发有效，有针对性且有效的治疗干预措施，以改善内分泌和代谢性疾病患者的健康状况。这些目标将在K23奖励期间通过追求3个总体培训和职业发展目标进行提出：首先，我将获得教学法 和技术知识对于成功设计和执行该领域的患者研究至关重要。在拟议的奖项的三年中，我将在内容区域专家顾问的指导下学习在体外和体内表型技术进行有价值的体外表型技术。具体而言，体外利用稳定的同位素和对“ Cybrid”细胞LNE的操纵，以及通过稳定同位素研究完成的高胰岛素 - 纤维血糖夹具的体内性能将是有效的技能。其次，我将接受原发性线粒体疾病患者的诊断，评估和管理方面的新专业知识。该人群在所有领域，特别是包括小儿内分泌学在内的较高信息的专科医生都有巨大的未满足的临床需求。他们进一步提供了一个重点机会，以研究线粒体功能障碍在常见内分泌疾病中的作用。通过为线粒体疾病患者提供临床护理并在体外和体内进行临床护理，可以实现此目标 研究投资以表征其血脂血症的程度和基础。第三，我将过渡到独立作为调查员。我将继续与我的心理委员会的专家成员一起工作和开发产品跨学科合作。我将通过完成拟议的研究，在全国会议上展示，在同行评审的期刊上发布并获得后来的R01资金，从而获得必要的专业知识，以过渡到独立性。执行此拟议项目将有助于实现这些目标。这些实验将测试我们的中心假设：[1]在原发性呼吸链（RC）损伤的情况下，细胞NAD+/NADH氧化还原平衡发生了变化，导致α-酮谷戊二烯（αkg）的脂肪脂质合成（αkg）的脂肪脂肪（αkg）的提高 - 柠檬酸盐和改善的脂肪酸氧化能力（FAO）和[2] 2] 2] [2] [2] [2]肌肉会引起骨骼肌胰岛素抵抗。为了检验这些假设，我们将同时采用体外和体内方法。我们将使用体外人类细胞系模型来测试RC抑制是否通过“反向”柠檬酸循环流量定量增加从头脂肪生成。一种完整的体内方法将寻求从头脂肪生成增加，肌肉脂质积累增加的证据，以及（i）原发性RC疾病，高甘油三酸酯血症但没有DM的（i）成年人的胰岛素敏感性提高。我们将将这一组与（ii）适当匹配的健康个体进行比较。为了评估“逆转”柠檬酸周期通量是否也可能导致“典型”非糖尿病肥胖个体中的高甘油三酸酯血症，我们还将研究（III）适当匹配的肥胖个体。将来，我们可以将这些研究的各个方面扩展到儿科人群。该项目在Chop和Penn利用许多独特的资源。首先，我的主要导师Marni J. Falk博士拥有大量且良好的型号的人群，这些患者对线粒体疾病的遗传诊断明确，提供了理想受试者和组织的现成来源，可以在其中进行拟议的研究。 CHOP的线粒体和表观基因组医学中心（CMEM）在该领域还提供了世界一流的基础设施。宾夕法尼亚州的糖尿病研究中心（DRC）已经拥有教师和核心专业知识，可以成功完成详细的代谢表型研究，其中关键的教师是合作伙伴。我们在宾夕法尼亚州高级磁共振成像和光谱中心（CAMRIS）的合作者开发了代谢成像技术，以估计和定位线粒体功能。这项工作将使我能够建立扎实的背景，从而追求未来，独立资助的有关线粒体，能量平衡和代谢在小儿内分泌疾病中的作用的研究