Bromine Inhalation Induced Lung Injury: Novel Mechanisms and Treatment Strategies

溴吸入引起的肺损伤：新机制和治疗策略

• 批准号: 9567726
• 负责人: Sadis Matalon
• 金额: $ 14.84万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-15 至 2020-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9567726
• 关键词: Accidents; Acetylcholine; Acids; Acute; Acute Lung Injury; Adult; Aerosols; Air; Airway Resistance; Aldehydes; Alveolar; Animal Model; Area; Asthma; Attenuated; Binding; Biochemical; Biological Markers; Blood gas; Breathing; Bromine; CD44 gene; Cells; Cessation of life; Chronic; Clinical Trials; Darkness; Data; Development; Dextrans; Disease; Disinfection; Effectiveness; Environment; Epithelial; Epithelial Cells; Europe; Event; Exposure to; Fiber; Fibrosis; Flame Retardants; Fluorescence; Fura-2; Gases; Gasoline; Glycosaminoglycans; Guanosine Triphosphate Phosphohydrolases; Halogens; Human; Human Pathology; Hyaluronan; Industrial Accidents; Industrialization; Inflammation; Inflammatory; Injury; Insecticides; Irrigation; Lead; Lipids; Liquid substance; Lung; Measurement; Measures; Mediating; Mediator of activation protein; Membrane Potentials; Mesenchymal; Molecular; Molecular Weight; Morphology; Mus; Muscle Cells; Muscle Contraction; Myosin Light Chains; Nose; Odors; Permeability; Phosphorylation; Physiological; Plasma; Plasma Proteins; Plasmalogens; Production; Public Health; Publishing; Pulmonary Edema; Pulmonary Fibrosis; Respiratory Failure; Rodent; Site; Small Interfering RNA; Smooth Muscle; Smooth Muscle Myocytes; Solid; Specific qualifier value; Structure of parenchyma of lung; Survivors; Syndrome; TLR4 gene; Testing; Time; Toxic effect; Transportation; Trypsin Inhibitors; Validation; Water; Wild Type Mouse; aerosolized; alveolar type II cell; base; cytokine; eosinophil; eosinophil peroxidase; experimental study; hypobromous acid; inhibitor/antagonist; inter-alpha-inhibitor; lung injury; male; methacholine; mortality; novel; palliative; patch clamp; public health relevance; repaired; respiratory smooth muscle; response; treatment strategy; vapor; Accidents; Acetylcholine; Acids; Acute; Acute Lung Injury; Adult; Aerosols; Air; Airway Resistance; Aldehydes; Alveolar; Animal Model; Area; Asthma; Attenuated; Binding; Biochemical; Biological Markers; Blood gas; Breathing; Bromine; CD44 gene; Cells; Cessation of life; Chronic; Clinical Trials; Darkness; Data; Development; Dextrans; Disease; Disinfection; Effectiveness; Environment; Epithelial; Epithelial Cells; Europe; Event; Exposure to; Fiber; Fibrosis; Flame Retardants; Fluorescence; Fura-2; Gases; Gasoline; Glycosaminoglycans; Guanosine Triphosphate Phosphohydrolases; Halogens; Human; Human Pathology; Hyaluronan; Industrial Accidents; Industrialization; Inflammation; Inflammatory; Injury; Insecticides; Irrigation; Lead; Lipids; Liquid substance; Lung; Measurement; Measures; Mediating; Mediator of activation protein; Membrane Potentials; Mesenchymal; Molecular; Molecular Weight; Morphology; Mus; Muscle Cells; Muscle Contraction; Myosin Light Chains; Nose; Odors; Permeability; Phosphorylation; Physiological; Plasma; Plasma Proteins; Plasmalogens; Production; Public Health; Publishing; Pulmonary Edema; Pulmonary Fibrosis; Respiratory Failure; Rodent; Site; Small Interfering RNA; Smooth Muscle; Smooth Muscle Myocytes; Solid; Specific qualifier value; Structure of parenchyma of lung; Survivors; Syndrome; TLR4 gene; Testing; Time; Toxic effect; Transportation; Trypsin Inhibitors; Validation; Water; Wild Type Mouse; aerosolized; alveolar type II cell; base; cytokine; eosinophil; eosinophil peroxidase; experimental study; hypobromous acid; inhibitor/antagonist; inter-alpha-inhibitor; lung injury; male; methacholine; mortality; novel; palliative; patch clamp; public health relevance; repaired; respiratory smooth muscle; response; treatment strategy; vapor

 DESCRIPTION (provided by applicant): Bromine (Br2) is a highly toxic dark-reddish liquid, which evaporates readily to a red vapor with a suffocating odor. World production of Br2 exceeds 300,000 tons per year. Exposure to Br2 causes acute lung injury, death from respiratory failure, and fibrosis. Because of the potential for industrial and transportation accidents to release of large amounts of Br2 in populated areas, Br2 presents a clear and present danger to public health. Few published studies have evaluated the acute and chronic sequelae of Br2 inhalation; treatment remains symptomatic and no effective countermeasures exist. Similar to human pathology, exposure of mice to Br2 causes reactive airway disease syndrome (RADS), increased permeability of the blood gas barrier to plasma proteins, and inflammation followed by sub-epithelial airway fibrosis and significant mortality. The overall purpose of this application is to identify the biochemical and molecular mechanisms responsible for these events and develop appropriate countermeasures. We propose that Br2 and hypobromous acid (HOBr-) interact with and fragment high molecular weight hyaluronan (H-HA), a ubiquitous matrix glycosaminoglycan, to generate highly inflammatory low molecular weight hyaluronan fragments (L-HA). L- HA binds to CD44 and Toll like receptor (TLR)-4, increases intracellular Ca+2 and activates TGF-1, and RhoA in lung epithelial and airway smooth muscle cells. These events lead to RADS, increased epithelial permeability to plasma proteins, epithelial-mesenchymal cell transition (EMT) of airway cells, sub-epithelial fibrosis, an death from respiratory failure. In addition, we demonstrate for the first time the formation of brominated lipids in the lungs and plasma of mice exposed to Br2. These compounds, formed by the interaction of Br2 with lung plasmalogens, mediate and amplify Br2 lung injury and act as biomarkers of Br2 exposure. Based on solid data we posit that post-Br2 exposure administration of aerosolized Yabro (a form of H-HA, currently in clinical trials in Europe for asthma), attenuates lung damage, enhances repair and decreases mortality. Experiments proposed in the first specific aim will assess physiological, biochemical, and morphological changes in mice exposed to Br2 and returned to room air for up to three weeks and test the effectiveness of aerosolized Yabro administered post exposure to decrease lung injury and mortality. We will then identify the mechanisms by which Br2 damages rodent and human airway smooth muscle (ASM), bronchial and alveolar type II (ATII) cells. We posit that Br2, brominated lipids, and L-HA increase intracellular Ca2+ and activate RhoA, which lead to increased airway contractility and epithelial permeability. Experiments will: (i) determine membrane potentials by patch clamp; (ii) intracellular Ca+2 by fura-2 fluorescence; (iii) RhoA and ROCK activation; (iv) myosin light chain phosphorylation; and (v) (for epithelial cells) permeability to fluorescent dextrans. Finally, we wll isolate mouse tracheal rings at 1, 24, and 72 hr. post Br2 exposure and measure smooth muscle contraction in response to methacholine.

 描述（由适用提供）：溴（BR2）是一种剧毒的深色红色液体，可轻松地蒸发到具有令人窒息的气味的红色蒸气中。 BR2的世界产量每年超过300,000吨。暴露于BR2会导致急性肺损伤，呼吸衰竭死亡和纤维化。由于工业和运输事故有可能在人口稠密的地区释放大量BR2，因此BR2对公共卫生构成了明显而当前的危险。很少有发表的研究评估了BR2吸入的急性和慢性后遗症。治疗仍然是有症状的，没有有效的对策。与人类病理类似，小鼠暴露于BR2会导致反应性气道疾病综合征（RAD），血液气屏障对血浆蛋白的渗透率增加，炎症随后是上皮呼吸道纤维化和显着的死亡率。本应用的总体目的是确定负责这些事件的生化和分子机制并产生适当的对策。我们提出BR2和低含量（HOBR-）与无处不在的基质基质糖胺聚糖相互作用，并与高分子量Hydrauronan（H-HA）相互作用，以产生高炎症的低分子量水力量化水龙碎片（L-HA）。 L-HA与CD44结合，像受体（TLR）-4一样，会增加细胞内Ca+2并激活TGF-1，而RhoA则在肺上皮和气道平滑肌细胞中。这些事件导致RAD，增加了对血浆蛋白的上皮通透性，气道细胞的上皮 - 间质细胞转变（EMT），上皮纤维化，呼吸衰竭死亡。此外，我们首次证明了暴露于BR2的小鼠的肺和血浆中溴化脂质的形成。这些化合物是由BR2与肺血浆元相互作用形成的，介导并扩增了BR2肺损伤并充当BR2暴露的生物标志物。基于可靠的数据，我们将BR2后的雾化Yabro的施用（一种H-HA的一种形式）（目前正在欧洲哮喘的临床试验中）降低了肺损伤，增强了修复并降低死亡率。第一个特定目标中提出的实验将评估暴露于BR2的小鼠的生理，生化和形态变化，并返回房间空气长达三个星期，并测试雾化Yabro的有效性，以减少肺部损伤和死亡率后接触后的疗法。然后，我们将确定BR2损害啮齿动物和人类气道平滑肌（ASM），支气管和牙槽II型（ATII）细胞的机制。我们肯定BR2，溴化脂质和L-HA会增加细胞内Ca2+并激活RhoA，这会导致实验：（i）通过斑块夹确定膜电位； （ii）Fura-2荧光细胞内Ca+2； （iii）Rhoa和岩石激活； （iv）肌球蛋白轻链磷酸化； （v）（对于上皮细胞）对荧光右旋的渗透性。最后，我们在1、24和72小时分离小鼠气管环。 BR2暴露后，并测量响应于甲基胆碱的平滑肌收缩。