Role of Mitochondria in Airway Smooth Muscle

线粒体在气道平滑肌中的作用

• 批准号: 8989155
• 负责人: Y. S. Prakash
• 金额: $ 47.85万
• 依托单位: MAYO CLINIC ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-12-22 至 2018-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8989155
• 关键词: Abate; Address; Affect; Agonist; Allergens; Antioxidants; Asthma; Buffers; Butyric Acids; Cell Proliferation; Cells; Chemicals; Chimeric Proteins; Chronic; Coupling; Disease; Endoplasmic Reticulum; Generations; Health; Healthcare; Human; Inflammation; Inflammatory; Interleukin-13; Lung diseases; Mediating; Mitochondria; Molecular Chaperones; Normal tissue morphology; Pathway interactions; Play; Reactive Oxygen Species; Role; Sarcoplasmic Reticulum; Smooth Muscle Myocytes; TNF gene; Testing; Therapeutic; Tissues; Treatment Efficacy; airway hyperresponsiveness; airway inflammation; airway remodeling; asthmatic; asthmatic patient; cell type; cytokine; endoplasmic reticulum stress; mouse model; new therapeutic target; novel; respiratory smooth muscle; response; success; tauroursodeoxycholic acid; uptake

 DESCRIPTION (provided by applicant): The proposed studies will address fundamental questions regarding the mechanisms underlying inflammation-induced enhancement of both hyperactive ("contractile") and proliferative ("synthetic") states of human airway smooth muscle (hASM), which are hallmarks of asthma. Identifying these mechanisms is the key to developing novel therapeutic targets for asthma. Our central hypothesis is that in hASM, inflammatory cytokines induce sarco-endoplasmic reticulum (SR/ER) stress leading to reduced expression of the mitochondrial fusion protein mitofusin 2 (Mfn2), and that this pathway plays a central role in asthma by triggering both hyper reactive (contractile) and proliferative (synthetic) states. Four Specific Aims are proposed: Specific Aim 1: To determine the impact of inflammatory cytokines on SR/ER stress, Mfn2 expression and mitochondrial fragmentation. In this aim, we will use dissociated hASM cells and tissue from normal and asthmatic patients to test the hypothesis that inflammatory cytokines trigger SR/ER stress due at least in part to an increase in ROS generation, and that SR/ER stress leads to reduced Mfn2 expression and increased mitochondrial fragmentation. Specific Aim 2: To determine the functional impact of SR/ER stress and reduced Mfn2 expression. In this aim, we will use dissociated hASM cells and tissue from normal and asthmatic patients to test the hypothesis that in hASM, inflammatory cytokine-induced SR/ER stress and reduced Mfn2 expression uncouples mitochondria and the SR/ER, thereby reducing mitochondrial Ca2+ buffering leading to elevated [Ca2+]cyt and force responses to agonist stimulation. Specific Aim 3: To determine the impact of SR/ER stress and reduced Mfn2 on hASM cell proliferation. In this aim, we will use dissociated hASM cells and tissue from normal and asthmatic patients to test the hypothesis that inflammatory cytokines increase hASM cell proliferation as a result of decreased Mfn2 expression. Specific Aim 4: To determine the efficacy of therapeutic approaches targeting SR/ER stress in alleviating airway hyper reactivity and remodeling in a mouse model of asthma. In this aim, we will use a mixed allergen mouse model to test the hypothesis that targeting SR/ER stress using chemical chaperones (e.g., 4-PBA, TUDCA) will provide an effective therapeutic strategy to reverse airway hyperactivity and blunt remodeling associated with asthma.

 描述（由适用提供）：拟议的研究将解决有关感染引起的过度活跃（“收缩”）和增殖（“合成”）人类气道平滑肌（HASM）状态的基本问题，这些状态是asthma的标志。识别这些机制是开发哮喘的新型治疗靶标的关键。我们的核心假设是，在HASM中，炎症细胞因子会影响肉类 - 肾上腺网状（SR/ER）应力，从而导致线粒体融合蛋白粒细化蛋白2（MFN2）的表达降低，并且该途径在哮喘中在哮喘中起着核心作用。提出了四个具体目的：具体目的1：确定炎症细胞因子对SR/ER应激，MFN2表达和线粒体片段的影响。在此目标中，我们将使用正常和哮喘患者分离的HASM细胞和组织来检验以下假设：炎性细胞因子触发SR/ER应激至少至少部分由于ROS的产生增加，而SR/ER应激会导致MFN2表达降低和MITOCHOCHRIALIALIALIALIALIALIALIALIAL碎片。特定目标2：确定SR/ER应力和MFN2表达降低的功能影响。在此目标中，我们将使用来自正常和哮喘患者的分离的HASM细胞和组织来检验以下假设：在HASM中，炎症性细胞因子诱导的SR/ER应激以及MFN2表达降低线粒体和SR/ER，从而减少了线粒体CAC2+ Bufferer，从而降低了线粒体CAC2+缓解效果的刺激。特定目标3：确定SR/ER应力和MFN2对HASM细胞增殖的影响。在此目标中，我们将使用正常患者和哮喘患者分离的HASM细胞和组织来测试炎性细胞因子会因MFN2表达降低而增加HASM细胞增殖的假设。特定目的4：确定针对SR/ER应力的理论方法的效率，以减轻哮喘小鼠模型中气道的过度反应性和重塑。在此目标中，我们将使用混合的过敏原小鼠模型来测试以下假设：使用化学伴侣（例如4-PBA，TUDCA）靶向SR/ER应力将提供有效的治疗策略，以逆转气道多动症和与哮喘相关的钝性重塑。