BLR&D Research Career Scientist Award Application

BLR

• 批准号: 10618269
• 负责人: Gary Cecchini
• 金额: --
• 依托单位: VETERANS AFFAIRS MED CTR SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-04-01 至 2025-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10618269
• 关键词: Alzheimer' s Disease; Amino Acids; Apoptosis; Architecture; Area; Award; Bacterial Model; Binding; Binding Proteins; Biochemical; Biochemistry; Bioenergetics; Brain Injuries; Cardiac; Cells; Clinical; Coenzyme Q10; Complex; DNA; Dedications; Development; Diabetes Mellitus; Diagnosis; Disease; Early Diagnosis; Enzymes; Epigenetic Process; Ethics; Family; Fumarates; Functional disorder; Gene Expression; Generations; Genes; Genetic Polymorphism; Genetic Transcription; Health; Heart Diseases; Heme; Homeostasis; Human; Human body; Hypoxia Inducible Factor; Inflammation; Inflammatory; Inflammatory Response; Injury; Investigation; Ischemia; Kidney Diseases; Laboratories; Laboratory Study; Lipids; Maintenance; Malignant Neoplasms; Malonates; Membrane; Methods; Minerals; Mitochondria; Mitochondrial Proteins; Modeling; Multienzyme Complexes; Multiple Sclerosis; Muscle Weakness; Mutation; Myocardial Infarction; NADH; NADH dehydrogenase (ubiquinone); Nerve Degeneration; Nerve Regeneration; Neurodegenerative Disorders; Nobel Prize; Organelles; Oxidation-Reduction; Oxidative Phosphorylation; Paper; Parkinson Disease; Pathway interactions; Patients; Permeability; Pharmaceutical Preparations; Philosophy; Physiology; Play; Point Mutation; Poison; Process; Procollagen-Proline Dioxygenase; Protein Region; Protons; Psoriasis; Publishing; Quinone Reductases; Reactive Oxygen Species; Regulatory Element; Relapse; Reperfusion Therapy; Research; Resolution; Respiration; Respiratory Chain; Roentgen Rays; Role; Science; Scientist; Series; Severities; Signal Transduction; Signaling Molecule; Stress; Stroke; Structure; Study models; Succinate Dehydrogenase; Succinates; System; Therapeutic; Therapeutic Uses; Time; Traumatic Brain Injury; Ubiquinone; United States National Academy of Sciences; Vascular remodeling; Veterans; Vitamins; Work; career; cofactor; design; healing; histone demethylase; in vivo; inhibitor; insight; member; method development; mitochondrial dysfunction; mitochondrial membrane; mitochondrial metabolism; mouse model; news; nuclear factor-erythroid 2; nucleotide metabolism; patient population; prevent; programs; protein complex; protein function; protein metabolism; protein structure; research and development; respiratory; response; small molecule inhibitor; success; three dimensional structure; tumor

Our laboratory is focused on understanding how mitochondrial function contributes to health and disease. As the major energy generating organelle of the cell dysfunction of mitochondria has been implicated in debilitating diseases prevalent in the VA patient population. These include, neurodegenerative diseases (Parkinson's, Alzheimer's), diabetes, cancer, and heart disease. Altered mitochondrial metabolism can result in changed levels of tricarboxylic (TCA) cycle metabolites, (such as succinate or fumarate), that act as signaling molecules to promote a pro-inflammatory state. This can lead to changes in gene transcription, through the induction of reactive oxygen species (ROS), stabilization of hypoxia- inducible factor-1α (HIF-1α), or the nuclear factor erythroid-2-related factor-2 (Nrf2) transcription pathway that responds to pro-inflammatory stress. Our laboratory investigates the structure and function of two essential members of the mitochondrial respiratory chain both of which reduce ubiquinone (CoQ10) used by the oxidative phosphorylation system to generate energy. We study the function of Complex I (NADH:ubiquinone oxidoreductase) which is the largest membrane-bound component of the mitochondrion. NADH generated by the TCA cycle is used by Complex I to reduce CoQ10 and this activity controls the NADH/NAD+ ratio. The enzyme is regulated by a structural change near the membrane domain termed the Active/De-Active (A/D) transition, which we first showed occurred in vivo. We also study succinate dehydrogenase (SDH/Complex II) which is a membrane-bound heterotetramer of dual function. SDH oxidizes succinate to fumarate in the TCA cycle while reducing CoQ10 for energy generation. Malfunction of SDH results in accumulation of succinate in the cell which promotes inflammation. It has been shown that inhibitors of SDH can have a positive effect in treating damage form ischemia/reperfusion in both stroke and cardiac models. Our studies of SDH have shown how the reversible inhibitor malonate binds to the enzyme and causes inhibition. We are now focused on understanding how we can regulate the activity and structure of both Complexes I & II so that this information can be used to treat disease. One model we will use is to investigate how TCA cycle metabolites can be used to treat traumatic brain injury (TBI) or stroke. Dimethyl fumarate (DMF) is an approved drug for treating relapsing multiple sclerosis and psoriasis and Dimethyl malonate (DMM) is a cell-permeable non-toxic compound which in vivo can be used to inhibit SDH. We hypothesize that in the brain injury model that DMM will block succinate accumulation following injury and prevent the signaling that produces ROS during ischemia/reperfusion; thus, reducing inflammation, the severity of the injury, and enhance healing. We use mouse models for these studies. We will also determine if the epigenetic modifier DMF can reduce the inflammation caused by TBI thus lessening the severity of the injury and enhance neuro-regeneration. We were the first to determine the x-ray structure of SDH and have provided major insight into its catalytic mechanism and function. How the enzyme complex is assembled, however, remains and area of intense investigation. We are now studying the assembly of human Complex II using known human assembly factors, needed for incorporation of redox cofactors necessary for function of the enzyme. It has been shown that when assembly is compromised this can lead to tumor formation in humans. We have had success expressing and analyzing the three-dimensional structure of the human structural subunits of SDH expressed in bacterial models. Thus, for the first time the structure of these assembly intermediates will be known. This information is needed to develop small molecule inhibitors/activators that can be used for treatment of diseases associated with mitochondrial dysfunction and control metabolite levels in cells.

我们的实验室专注于了解线粒体功能如何有助于健康， 疾病线粒体作为细胞功能障碍的主要能量产生细胞器， 与VA患者人群中普遍存在的衰弱性疾病有关。其中包括神经退行性疾病 疾病（帕金森氏症，阿尔茨海默氏症），糖尿病，癌症和心脏病。线粒体改变 代谢可导致三羧酸（TCA）循环代谢物（如琥珀酸或琥珀酸）的水平改变。 富马酸盐），其充当信号分子以促进促炎状态。这可能会导致 基因转录，通过诱导活性氧（ROS），稳定缺氧- 诱导因子-1 α（HIF-1α）或核因子红细胞-2相关因子-2（Nrf 2）转录途径 对促炎性压力有反应我们的实验室研究了两个 线粒体呼吸链的重要成员，两者都减少辅酶Q10的使用， 氧化磷酸化系统产生能量。我们研究了复合物I的功能 (NADH：泛醌氧化还原酶），其是辅酶的最大膜结合组分。 由TCA循环产生的NADH被复合物I用于还原辅酶Q10，并且该活性控制辅酶Q10的代谢。 NADH/NAD+比率。该酶受膜结构域附近的结构变化调节，称为膜结构域。 主动/去主动（A/D）转换，我们首先表明发生在体内。我们也研究琥珀酸 脱氢酶（SDH/复合物II），其是具有双重功能的膜结合异源四聚体。SDH 在TCA循环中将琥珀酸氧化为富马酸，同时减少辅酶Q10以产生能量。故障 SDH导致琥珀酸在细胞中积累，从而促进炎症。已经显示 SDH的抑制剂在治疗中风和中风中的缺血/再灌注损伤方面具有积极作用， 心脏模型我们对SDH的研究表明了可逆抑制剂丙二酸是如何与酶结合的 并引起抑制。我们现在的重点是了解我们如何能够调节活动， 因此，我们需要研究复合物I和II的结构，以便这些信息可以用于治疗疾病。 我们将使用的一个模型是研究TCA循环代谢物如何用于治疗创伤性 脑损伤（TBI）或中风。富马酸二甲酯（DMF）是一种获批用于治疗复发性多发性硬化症的药物， 而丙二酸二甲酯（DMM）是一种细胞可渗透的无毒化合物， 可用于体内抑制SDH。我们假设在脑损伤模型中，DMM会阻断 琥珀酸积累损伤后，并阻止信号，产生ROS的过程中 缺血/再灌注;因此，减少炎症，损伤的严重性，并增强愈合。我们使用 这些研究的小鼠模型。我们还将确定表观遗传修饰剂DMF是否可以减少 因此，TBI可以减轻由TBI引起的炎症，从而减轻损伤的严重程度并增强神经再生。 我们是第一个确定SDH的X射线结构，并提供了对其结构的主要见解。 催化机理和作用然而，酶复合物是如何组装的， 紧张的调查。我们现在正在研究使用已知的人类复合物II的组装。 组装因子，需要掺入酶功能所必需的氧化还原辅因子。它有 已经表明，当组装受损时，这可能导致人类肿瘤的形成。我们有 成功表达和分析了SDH的人体结构亚基的三维结构 在细菌模型中表达。因此，这些组装中间体的结构将首次被 知道的需要这些信息来开发小分子抑制剂/激活剂，其可用于 治疗与线粒体功能障碍相关的疾病和控制细胞中的代谢物水平。