The Role of phosphoenolpyruvate carboxykinase and reactive oxygen species in the

磷酸烯醇丙酮酸羧激酶和活性氧在

• 批准号: 8018129
• 负责人: Jason Earl Podrabsky
• 金额: $ 36.5万
• 依托单位: PORTLAND STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-01-15 至 2013-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8018129
• 关键词: Acids; Address; Aerobic; Affect; Alanine; Amaze; Animals; Anoxia; Biochemical; Biochemical Pathway; Biology; Brain; Carbon; Cell Death; Cell physiology; Cells; Cessation of life; Characteristics; Citric Acid Cycle; Coupled; Cyprinodontidae; Cytoplasm; Data; Detection; Development; Diapause; Embryo; Embryonic Development; Engineering; Enzymes; Event; Exhibits; Exposure to; Fishes; Fluorescent Probes; Fundulus heteroclitus; Generations; Genetic; Genomics; Glycolysis; Guanosine Triphosphate; Heart; Heart Diseases; High Pressure Liquid Chromatography; Hour; Human; Human Development; Immunohistochemistry; Kinetics; Knowledge; Light; Mediating; Membrane Potentials; Metabolic; Metabolic Pathway; Metabolism; Methodology; Mitochondria; Modeling; Molecular; Morbidity - disease rate; Myocardial Infarction; Natural Selections; Nature; Organism; Oxygen; Pattern; Phosphocreatine; Phosphoenolpyruvate Carboxylase; Physiological; Physiological Adaptation; Physiology; Process; Production; Protein Biosynthesis; Reactive Oxygen Species; Recovery; Reporting; Role; Sampling; Source; Stroke; Succinates; System; Testing; Time; Tissues; Vertebrates; Writing; Yolk Cell; base; brain cell; brain tissue; deprivation; embryo cell; enzyme activity; gamma-Aminobutyric Acid; heart cell; inhibitor/antagonist; inorganic phosphate; metabolomics; methylxanthine; mitochondrial membrane; novel; oxidation; prevent; public health relevance; research study; response

DESCRIPTION (provided by applicant): Almost all organisms on Earth share the basic metabolic pathways that support anaerobic metabolism, and yet many organisms, including most vertebrates, cannot survive for long without molecular oxygen. Embryos of the annual killifish Austrofundulus limnaeus are an excellent model for investigating the mechanistic basis of anoxia-tolerance and anoxia-sensitivity in vertebrates. Embryos of A. limnaeus undergo a unique period of developmental dormancy called diapause. Recent evidence suggests that embryos of A. limnaeus have some very unique physiological adaptations that are associated with tolerance of long-term anoxia. Both dormant and actively developing embryos of A. limnaeus can survive for months without oxygen at 250C. Embryos of A. limnaeus display a massive depletion of ATP during the initial hours of anoxic exposure and lose their mitochondrial membrane potential during this same time frame. These two events are typically associated with cell death in other vertebrate cells, but embryos of A. limnaeus quickly recover from these drastic changes in mitochondrial physiology and energetics. These observations imply that cells of A. limnaeus embryos have some extraordinary characteristics compared to other vertebrates, and even to other vertebrates that exhibit substantial tolerance of anoxia. I will identify the metabolic pathways that support anoxia tolerance in isolated cells of A. limnaeus, assess mitochondrial function and energetics during anoxia and recovery from anoxia, and test the hypothesis that an alternate metabolic pathways supported by the enzyme phosphoenolpyruvate carboxykinase is critical for the survival of anoxia. By using the integrative approaches outlined in the proposal we can hopefully create a more complete picture of the cellular physiology of anoxia-tolerance in the cells if this exceptional vertebrate extremophile. PUBLIC HEALTH RELEVANCE: Heart disease and stroke are responsible for the vast majority of deaths in the developed world. The extreme sensitivity of human heart and brain tissue to lack of oxygen is poorly understood at the cellular level. By understanding the cellular mechanisms that support extreme anoxia tolerance in embryos of the annual killifish, Austrofundulus limnaeus, we may be able to develop treatments to mediate or prevent the damaging effects of heart attacks and strokes to humans.

描述（由申请人提供）：地球上几乎所有生物体都具有支持无氧代谢的基本代谢途径，但许多生物体，包括大多数脊椎动物，在没有分子氧的情况下无法长期生存。一年生鳉鱼 Austrofundulus limnaeus 的胚胎是研究脊椎动物耐缺氧和缺氧敏感性机制基础的绝佳模型。 A. limnaeus 的胚胎经历一个独特的发育休眠期，称为滞育。最近的证据表明，A. limnaeus 的胚胎具有一些非常独特的生理适应，这些适应与长期缺氧的耐受性有关。处于休眠状态和活跃发育状态的 A. limnaeus 胚胎在 250℃ 的无氧环境下均可存活数月。在缺氧暴露的最初几个小时内，A. limnaeus 的胚胎表现出 ATP 的大量消耗，并在同一时间范围内失去线粒体膜电位。这两个事件通常与其他脊椎动物细胞的细胞死亡有关，但利姆奈乌斯的胚胎很快就能从线粒体生理学和能量学的这些剧烈变化中恢复过来。这些观察结果表明，与其他脊椎动物，甚至与其他表现出对缺氧具有显着耐受性的脊椎动物相比，A. limnaeus 胚胎细胞具有一些非凡的特征。我将确定支持A. limnaeus分离细胞耐缺氧的代谢途径，评估缺氧期间和缺氧恢复期间的线粒体功能和能量学，并测试由磷酸烯醇丙酮酸羧激酶支持的替代代谢途径对于缺氧生存至关重要的假设。通过使用提案中概述的综合方法，我们有望对这种特殊的脊椎动物极端微生物的细胞耐缺氧的细胞生理学产生更完整的了解。 公共卫生相关性：心脏病和中风是发达国家绝大多数死亡的原因。在细胞水平上，人们对人类心脏和脑组织对缺氧的极端敏感性知之甚少。通过了解一年生鳉鱼Austrofundulus limnaeus胚胎中支持极端缺氧耐受性的细胞机制，我们也许能够开发出治疗方法来介导或预防心脏病和中风对人类的破坏性影响。