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.

我们的实验室致力于了解线粒体功能如何促进健康和 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 患者群体中流行的衰弱性疾病有关。这些包括，神经退行性 疾病（帕金森病、阿尔茨海默病）、糖尿病、癌症和心脏病。线粒体改变 代谢可能导致三羧酸 (TCA) 循环代谢物（例如琥珀酸或 富马酸），作为信号分子促进促炎状态。这可能会导致以下方面的变化 基因转录，通过诱导活性氧（ROS），稳定缺氧 诱导因子 1α (HIF-1α) 或核因子红细胞 2 相关因子 2 (Nrf2) 转录途径 对促炎应激作出反应。我们的实验室研究了两种物质的结构和功能 线粒体呼吸链的重要成员，两者都减少了所使用的泛醌 (CoQ10) 氧化磷酸化系统产生能量。我们研究复合物 I 的功能 （NADH：泛醌氧化还原酶）是线粒体最大的膜结合成分。 复合物 I 使用 TCA 循环产生的 NADH 来还原 CoQ10，并且该活性控制 NADH/NAD+ 比率。该酶受到膜结构域附近的结构变化的调节，称为 我们首先证明其发生在体内的活性/去活性（A/D）转换。我们还研究琥珀酸 脱氢酶（SDH/Complex II）是一种具有双重功能的膜结合异四聚体。 SDH 在 TCA 循环中将琥珀酸氧化为富马酸，同时还原 CoQ10 以产生能量。故障 SDH 导致琥珀酸盐在细胞内积聚，从而促进炎症。事实证明 SDH 抑制剂对治疗中风和缺血/再灌注损伤具有积极作用 心脏模型。我们对 SDH 的研究表明了可逆抑制剂丙二酸如何与酶结合 并引起抑制。我们现在专注于了解如何规范该活动并 复合物 I 和 II 的结构，以便该信息可用于治疗疾病。 我们将使用的一个模型是研究如何使用 TCA 循环代谢物来治疗创伤 脑损伤（TBI）或中风。富马酸二甲酯（DMF）是一种批准用于治疗复发性多发性骨髓瘤的药物 硬化症和牛皮癣，丙二酸二甲酯 (DMM) 是一种细胞渗透性无毒化合物， 体内可用于抑制SDH。我们假设在脑损伤模型中 DMM 会阻断 损伤后琥珀酸的积累，并阻止在损伤期间产生 ROS 的信号传导 缺血/再灌注；因此，可以减轻炎症、减轻损伤的严重程度并促进愈合。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 TBI 引起的炎症可以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 射线结构的人，并对其提供了重要的见解 催化机制和功能。然而，酶复合物的组装方式仍然存在争议。 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，需要掺入酶功能所需的氧化还原辅因子。它有 研究表明，当组装受到损害时，可能会导致人类形成肿瘤。我们有过 成功表达并分析SDH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 已知。需要这些信息来开发可用于 治疗与线粒体功能障碍相关的疾病并控制细胞内的代谢水平。