The role of ROS on beta-2-adrenergic receptor function in human airway

ROS对人气道β2-肾上腺素能受体功能的作用

基本信息

批准号：
10513954
负责人：
Nader H Moniri
金额：
$ 42.45万
依托单位：
MERCER UNIVERSITY MACON
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-07-01 至 2025-08-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10513954
关键词：
Acids Agonist Airway Disease Alkylation Animal Model Area Asthma Biochemical Biomedical Research Bronchial Spasm Bronchodilation Bronchodilator Agents Cell Line Cell model Cells Chronic Clinical Clone Cells Coupled Cyclic AMP Cyclic AMP-Dependent Protein Kinases Cysteine Data Development Disease Environment Epinephrine Epithelial Cells Etiology Feedback Functional disorder Funding Mechanisms G-Protein-Coupled Receptors GTP-Binding Proteins Generations Goals Gold Grant Human Hydrogen Peroxide Inflammatory Inhalation Laboratories Lead Light Lung Mediating Norepinephrine Organ Oxidation-Reduction Oxidative Stress Oxides Patients Physiological Physiology Post-Translational Protein Processing Process Production Proteins Reactive Inhibition Reactive Oxygen Species Renal function Research Resources Role Signal Transduction Signaling Protein Steroids Students Sulfenic Acids Superoxides System Tachyphylaxis Testing Time Tissues Treatment Failure Work airway epithelium airway inflammation airway obstruction asthmatic beta-2 Adrenergic Receptors beta-arrestin cell type chronic inflammatory lung disease clinically relevant constriction cysteinesulfenic acid heart function knowledge base member oxidation protein function pulmonary function receptor receptor function reduce symptoms response standard care undergraduate student

项目摘要

PROJECT ABSTRACT Asthma is a chronic inflammatory disease of the lungs that is characterized by airway obstruction and bronchospasm. While there are many factors that contribute to development of asthma and other inflammatory airway diseases, the generation of reactive oxygen species (ROS) within the airway epithelium leads to exacerbation of airway inflammation and contributes greatly to pathophysiology of asthma. The gold-standard for treatment of asthma is inhalation of β2-adrenergic receptor (β2AR) agonists, which relax the airway tissues and reduce bronchospasms, allowing for greater pulmonary function. However, chronic use of β2-agonists leads to loss of bronchodilatory efficacy, a process termed β2-agonist tachyphylaxis, and for which, no mechanistic explanation exists. Recently, our laboratory has demonstrated that agonism of β2AR leads to robust formation of ROS, and that ROS are required for β2AR function, as inhibition of ROS abrogates both β2AR-mediated G-protein and β-arrestin signaling. These results suggest that some level of ROS are required for stabilization of functional β2AR, and indeed, we show that β2AR function is strictly regulated by ROS- dependent transient oxidation of β2AR-cysteine residues to form cysteine-S-Sulfenic acids, an effect that significantly influences receptor function. Importantly, our results also suggest that over-oxidation of β2AR S- Sulfenic acids to higher-order irreversible oxidation states inhibits β2AR function. We hypothesize that the highly oxidative environment of asthma, coupled with the heightened ROS generation upon chronic β2-agonist use, could contribute to β2-agonist tachyphylaxis by causing over-oxidation of β2AR. The overall goal of this project is to examine the mechanisms of ROS generation in normal and asthma-diseased primary airway epithelial cells and to test the hypothesis that over-oxidation of β2AR facilitates clinical tachyphylaxis. We proposed two specific aims, using both primary human airway epithelial cells and animal models of chronic and severe asthma, to reach our goals: [1] To characterize the cellular mechanisms of β2AR-induced ROS generation in normal and asthma-diseased airway epithelial cells [2] To assess the effects of β2AR oxidation on β2-agonist tachyphylaxis. Results of this research will shed important light on the role of ROS as regulators of β2AR function in asthma, and reveal the importance of ROS and β2AR oxidation in facilitating clinical tachyphylaxis.

项目摘要哮喘是一种肺部慢性炎症性疾病，其特征是气道阻塞和虽然有许多因素会导致哮喘和其他炎症的发生。气道疾病，气道上皮内活性氧（ROS）的产生导致气道炎症加剧，对哮喘的病理生理学有很大贡献。治疗哮喘的方法是吸入 β2-肾上腺素能受体 (β2AR) 激动剂，它可以放松气道组织并减少支气管痉挛，从而增强肺功能，但长期使用β2受体激动剂。导致支气管扩张功效丧失，这一过程称为 β2 激动剂快速耐受，对此，没有最近，我们的实验室已经证明β2AR的激动作用是存在的。 ROS 的强大形成，并且 ROS 是 β2AR 功能所必需的，因为 ROS 的抑制会消除两者 β2AR 介导的 G 蛋白和 β-arrestin 信号传导这些结果表明需要一定水平的 ROS。稳定功能性 β2AR，事实上，我们表明 β2AR 功能受到 ROS 的严格调节 β2AR-半胱氨酸残基依赖瞬时氧化形成半胱氨酸-S-磺酸，这种作用重要的是，我们的结果还表明 β2AR S- 的过度氧化。我们发现，高阶不可逆氧化态的磺酸会抑制 β2AR 功能。哮喘的高氧化环境，加上慢性 β2 激动剂引起的哮喘 ROS 生成使用，可能通过引起 β2AR 过度氧化而促进 β2 激动剂快速耐受。该项目旨在研究正常和哮喘病初级气道中 ROS 生成的机制上皮细胞并检验 β2AR 过度氧化促进临床快速耐受的假设。提出了两个具体目标，使用原代人气道上皮细胞和慢性和慢性疾病动物模型严重哮喘，以实现我们的目标：[1] 表征 β2AR 诱导 ROS 的细胞机制在正常和哮喘病气道上皮细胞中生成 [2] 评估 β2AR 氧化的影响这项研究的结果将为 ROS 作为调节剂的作用提供重要的启示。 β2AR 在哮喘中的功能，并揭示 ROS 和 β2AR 氧化在促进临床中的重要性快速耐受。