BLR&D Research Career Scientist Award Application

BLR

• 批准号: 10265408
• 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/10265408
• 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; 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; Lead; 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; Oxides; 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; Three-dimensional analysis; 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/antagonist; 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 metabolism; protein structure; protein structure function; 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有助于健康和 疾病。作为细胞的主要能量产生细胞器，线粒体的功能障碍一直是 与退伍军人管理局患者群体中流行的衰弱疾病有关。这些包括，神经退行性变 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 新陈代谢会导致三羧酸(TCA)循环代谢物的水平发生变化，如琥珀酸或 富马酸)，作为促进促炎状态的信号分子。这可能会导致 基因转录，通过诱导活性氧物种(ROS)，稳定低氧- 诱导因子-1α(HIF-1α)或核因子红系相关因子-2(NRF2)转录途径 这是对促炎压力的反应。我们的实验室研究了两个分子的结构和功能 线粒体呼吸链的基本成员，两者都能减少辅酶Q10的使用 氧化磷酸化系统产生能量。我们研究了复合体I的功能 (NADH：泛醌氧化还原酶)，是线粒体最大的膜结合成分。 由TCA循环产生的NADH被复合体I用来减少CoQ10，并且这一活动控制 NADH/NAD+比值。这种酶由膜结构域附近的一种结构变化调节，称为 活动/非活动(A/D)转换，这是我们首次在体内发现的。我们也研究琥珀酸 脱氢酶(SDH/Complex II)是一种膜结合型双功能异四聚体。SDH 在三氯乙烷循环中氧化琥珀酸为富马酸，同时降低辅酶Q10以产生能量。的故障。 琥珀酸脱氢酶导致琥珀酸在细胞内积累，从而促进炎症。事实证明， SDH抑制剂在治疗卒中和脑缺血再灌注损伤中具有积极作用 心脏模型。我们对SDH的研究表明，可逆抑制剂丙二酸是如何与酶结合的 并导致抑制。我们现在专注于了解我们如何规范这一活动，并 两个复合体I和II的结构，以便这些信息可用于治疗疾病。 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 脑损伤(TBI)或中风。富马酸二甲酯(DMF)是一种被批准用于治疗复发性多发性 硬化症和银屑病和丙二酸二甲酯(DMM)是一种细胞渗透性无毒化合物，在 VIVO可用于抑制SDH。我们假设在脑损伤模型中DMM将阻断 损伤后琥珀酸积累并阻止在损伤过程中产生ROS的信号转导 缺血/再灌注；因此，减轻炎症，减轻损伤的严重程度，并促进愈合。我们用 用于这些研究的小鼠模型。我们还将确定表观遗传修饰剂DMF是否可以降低 颅脑损伤引起的炎症因此减轻了损伤的严重程度，并增强了神经再生。 我们首先确定了sdh的x射线结构，并提供了对它的主要见解。 催化机理和功能。然而，酶复合体是如何组装的，仍然是 严密的调查。我们现在正在研究人类复合体II的组装。 整合酶功能所必需的氧化还原辅因子所需的组装因子。它有 已经证明，当组装受到损害时，这可能会导致人类肿瘤的形成。我们已经有了 成功表达和分析人类SDH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是第一次 为人所知。这些信息是开发小分子抑制剂/激活剂所必需的，这些小分子抑制剂/激活剂可以用于 治疗与线粒体功能障碍相关的疾病，控制细胞中的代谢物水平。