Antidote for inhaled CO poisoning based on mutationally engineered neuroglobin

基于突变工程神经球蛋白的吸入一氧化碳中毒解毒剂

• 批准号: 9389399
• 负责人: Mark T Gladwin
• 金额: $ 57.43万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-12-01 至 2018-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9389399
• 关键词: Acute; Address; Affect; Affinity; Alanine; Animal Model; Antidotes; Apoptosis; Binding; Biological; Biological Response Modifier Therapy; Blood Circulation; Blood gas; Brain; Brain Edema; Brain Injuries; Carbon Monoxide; Carbon Monoxide Poisoning; Carboxyhemoglobin; Cardiac; Carrying Capacities; Cause of Death; Cessation of life; Cities; Clinical Data; Cognitive; Data; Development; Diagnosis; Distal; Electron Transport; Emergency department visit; Engineering; Enzymes; Erythrocytes; Excision; Exhibits; Exposure to; Family suidae; Fire - disasters; Functional disorder; Gas Poisoning; Gases; Genus Hippocampus; Glutamine; Half-Life; Heart; Heme; Heme Iron; Hemeproteins; Hemoglobin; Hemoglobin concentration result; Histidine; Home environment; Human; Human Engineering; Hyperbaric Oxygen; Hyperbaric Oxygenation; Hyperbaric Therapy; Hypoxia; Image; Impaired cognition; In Vitro; Incubated; Infusion procedures; Inhalation; Injury; Intensive Care; Kidney; Laboratories; Lasers; Leucine; Ligands; Lung; Magnetic Resonance Imaging; Mammals; Measures; Mechanical ventilation; Metabolic Clearance Rate; Metabolic acidosis; Methodology; Mitochondria; Modeling; Mus; Mutagenesis; Mutation; Myoglobin; Necrosis; Neuraxis; Neurocognitive Deficit; Neurologic; Normal Range; Organ; Oxygen; Oxygen Therapy Care; Paramedical Personnel; Pathologic; Patients; Persons; Physiology; Plants; Poisoning; Preparation; Reperfusion Injury; Respiration; Risk; Saline; Series; Solubility; Structure; Sulfhydryl Compounds; Surface; System; Testing; Time; Tissues; Transportation; United States; Urine; Water; autooxidation; base; capsule; clinical development; combinatorial; complex IV; cytochrome c oxidase; disability; exhaust; experimental study; extracellular; flash photolysis; improved; in vivo; mutant; neuroglobin; planetary Atmosphere; pre-clinical; pressure; public health relevance; systemic toxicity; translational study

DESCRIPTION (provided by applicant): Blood gas poisoning with carbon monoxide (CO) remains a major cause of death and disability, affecting 50,000 persons a year in the U.S. alone. Patients with greater than 30% carboxyhemoglobinemia may develop brain injury, long-term neurocognitive deficits, and/or death. In the present proposal we introduce the first antidotal therapy for carbon monoxide poisoning, based on the finding of a surprising and near-irreversible CO-binding affinity of mutationally engineered human neuroglobin. Neuroglobin, like cytoglobin and many plant Hbs, is a six-coordinate hemoprotein, with the heme iron coordinated by a proximal and distal histidine residues. In an effort to understand the function of this bis-histidyl structure, we performed mutagenesis of the proximal histidine 64 molecule (e.g. H64Q) which opens the heme pocket, forming a five-coordinate molecule, more similar to the heme pocket of Hb or myoglobin. Unexpectedly, this molecule exhibits a remarkably high affinity for gaseous ligands, with a P50 value for oxygen (PaO2 value at which 50% of the heme binds oxygen) of 0.01 mm Hg (normal value is 26 mm Hg). This finding informs our primary hypothesis, that H64 mutant neuroglobin will bind CO with high affinity, producing a five-coordinate "trap" for CO. In our preliminary experiments we find that mutationally engineered H64Q neurglobin binds CO with an affinity more than 300 times that of hemoglobin and can remove CO from intact red cells in vitro and in vivo in CO exposed mice in less than 2 minutes. We propose to refine this molecule in a series of in vitro, pre-clinical physiology, and translational studies as a human biological antidote for CO poisoning and test its ability to clear CO from red blood cells, critical organs (lung, brain, and heart), and cytochrome C oxidase of the mitochondrial electron transport chain. From a translational perspective, will test the ability of this antidote to improve long-term organ function and survival after severe CO poisoning.

描述（由申请人提供）：一氧化碳（CO）的血液中毒仍然是死亡和残疾的主要原因，仅在美国就会影响50,000人。羧基血红蛋白血症大于30％的患者可能会出现脑损伤，长期神经认知缺陷和/或死亡。在本提案中，我们基于发现突变设计的人类神经蛋白的令人惊讶且近乎不可逆转的共同结合亲和力，引入了第一种用于一氧化碳中毒的解毒疗法。神经白蛋白，例如细胞珠蛋白和许多植物HB，是一种六坐标的血源蛋白，血红素铁由近端和远端组氨酸残基配位。为了理解这种双基烷基结构的功能，我们进行了近端组氨酸64分子（例如H64Q）的诱变，该分子（例如H64Q）打开血红素袋，形成了五倍坐标分子，更类似于HB或肌球蛋白的血红素袋。出乎意料的是，该分子对气态配体具有很高的亲和力，氧气（PAO2值的PAO2值）为0.01 mm Hg（正常值为26 mm Hg），氧气为P50值（PAO2值）。 This finding informs our primary hypothesis, that H64 mutant neuroglobin will bind CO with high affinity, producing a five-coordinate "trap" for CO. In our preliminary experiments we find that mutationally engineered H64Q neurglobin binds CO with an affinity more than 300 times that of hemoglobin and can remove CO from intact red cells in vitro and in vivo in CO exposed mice in less than 2 分钟。我们建议在一系列体外，临床前的生理学和翻译研究中完善该分子，作为人类生物学解毒剂，用于CO中毒，并测试其清除的能力 来自红细胞，临界器官（肺，脑和心脏）以及线粒体电子传输链的细胞色素C氧化酶的CO。从转化的角度来测试能力 这种解毒剂改善了严重的CO中毒后的长期器官功能和存活。