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

基本信息

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
项目类别：
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

项目摘要

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) 血气中毒仍然是死亡和残疾的主要原因，仅在美国每年就有 50,000 人受到影响。碳氧血红蛋白血症超过 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，我们基于突变工程人类神经球蛋白令人惊讶且几乎不可逆的CO结合亲和力的发现，介绍了针对一氧化碳中毒的第一种解毒疗法。神经球蛋白与细胞球蛋白和许多植物血红蛋白一样，是一种六配位血红蛋白，其中血红素铁由近端和远端组氨酸残基协调。为了了解这种双组氨酸结构的功能，我们对近端组氨酸 64 分子（例如 H64Q）进行了诱变，该分子打开血红素口袋，形成五配位分子，更类似于 Hb 或肌红蛋白的血红素口袋。出乎意料的是，该分子对气态配体表现出非常高的亲和力，氧的 P50 值（50% 的血红素与氧结合时的 PaO2 值）为 0.01 mm Hg（正常值为 26 mm Hg）。这一发现为我们的主要假设提供了依据，即 H64 突变型神经球蛋白将以高亲和力结合 CO，从而为 CO 产生五坐标“陷阱”。在我们的初步实验中，我们发现突变工程 H64Q 神经球蛋白结合 CO 的亲和力是普通神经球蛋白的 300 倍以上。血红蛋白，并且可以在不到 2 分钟的时间内从体外和体内暴露于 CO 的小鼠的完整红细胞中去除 CO。我们建议通过一系列体外、临床前生理学和转化研究来完善该分子，作为人类一氧化碳中毒的生物解毒剂，并测试其清除二氧化碳的能力。来自红细胞、重要器官（肺、脑和心脏）的 CO 以及线粒体电子传递链的细胞色素 C 氧化酶。从翻译的角度来说，会考验能力这种解毒剂可改善严重一氧化碳中毒后的长期器官功能和生存率。