Therapeutic Potentiation of Bronchial Dilatation

支气管扩张的治疗增强作用

基本信息

批准号：
8259736
负责人：
Jeffrey J Fredberg
金额：
$ 45.57万
依托单位：
UNIVERSITY OF CHICAGO
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-05-01 至 2014-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8259736
关键词：
2-cyclopentyl-5-(5-isoquinolylsulfonyl)-6-nitro-1H-benzo(D)imidazole Acetylcholine Actins Adrenal Cortex Hormones Adrenergic Agonists Adverse effects Affect Asthma Atomic Force Microscopy Attention Biological Assay Boa Breathing Bronchoconstriction Bronchodilator Agents Calcium Canis familiaris Cardiac Cells Cessation of life Chemosensitization Complex Contracts Developed Countries Dilatation - action Dose Drug Controls Drug Delivery Systems Drug effect disorder Environmental air flow Evaluation Exposure to Failure Filament Freezing Generations Guidelines HSPB1 gene Human Individual Inflammation Instruction Intervention Length Lung Microfilaments Minority Muscle Muscle Cells Muscle Contraction Myosin ATPase Myosin Light Chains Obstruction Pathway interactions Patients Pharmaceutical Preparations Phosphorylation Population Principal Investigator Public Health Relative (related person)Risk Role Screening procedure Side Signal Pathway Slice Smooth Muscle Smooth Muscle Myocytes Smooth Muscle Myosins Solutions Staging Subgroup Symptoms Testing Therapeutic Therapeutic Effect Thick Time Tomogram Traction Work of Breathing airway inflammation base design high throughput screening improved meetings novel novel strategies novel therapeutics omalizumab polymerization reconstruction release of sequestered calcium ion into cytoplasm respiratory smooth muscle skeletal therapeutic target

项目摘要

DESCRIPTION (provided by applicant): Given its central role in asthmatic airflow obstruction, airway smooth muscle (ASM) contraction has long received attention as a therapeutic target, with strategies directed at relaxing ASM or ablating ASM altogether. Here, we propose an entirely novel approach to relieving airflow obstruction in asthma. Our strategy is to impair the ability of contracted ASM to remain shortened after contraction has occurred. While ASM that has contracted against a steady load can remain shortened indefinitely, ASM contracting against a fluctuating load first shortens then relengthens; such force fluctuation-induced relengthening (FFIR) can be quite substantial and can be further enhanced pharmacologically. In the intact lung, ASM is constantly exposed to force fluctuations imposed by tidal breathing. The key premise of this application is that drugs targeted specifically to exaggerate breathing-induced FFIR should release ASM's squeeze on the airway lumen and thus relieve bronchoconstriction. Our objective is to identify and evaluate compounds that target this extremely potent but largely unstudied bronchodilatory pathway. Preliminary studies disclose disruption of actin-myosin-actin connectivity (AMAC) as an attractive strategy for enhancing FFIR. In isolated ASM, interventions that reduce the polymerization of actin or myosin filaments both reduce AMAC and promote FFIR. In a staged screening design, we will use large scale high throughput primary assays to identify novel or already-in-human compounds that: 1) inhibit polymerization of myosin into thick myofilaments; and/or 2) reduce force generation by cultured human ASM. A novel low throughput assay will then be used to test which of these compounds potentiates FFIR or inhibits bronchoconstriction in intact airways within precision- cut thin slices of human lungs. Finally, we will evaluate mechanisms of drug action by quantifying myofila}} ment lengths in flash frozen control and drug-treated intact human ASM using 3D reconstructions of myofila}} ment ultrastructure from EM tomograms, and by assessing potential alternative mechanisms of drug action, including alteration of intracellular calcium mobilization, MLC20 phosphorylation, and/or HSP27 phosphoryl}} ation. Our results should identify novel drugs for asthma that potentiate FFIR or inhibit bronchoconstriction. RELEVANCE (See instructions): The objective of this project is to identify drugs that could exert a novel therapeutic effect in asthma - by promoting the rapid reversal of bronchoconstriction. This approach is fully complementary to current therapeutic approaches aimed at suppressing airway inflammation or relaxing airway muscle and so, if developed successfully, should add an entirely new therapeutic strategy to existing asthma therapies.

描述（由申请人提供）：鉴于其在哮喘气流阻塞中的核心作用，气道平滑肌（ASM）收缩长期以来作为治疗目标而受到关注，其策略旨在放松 ASM 或完全消除 ASM。在这里，我们提出了一种全新的方法来缓解哮喘气流阻塞。我们的策略是削弱收缩后 ASM 保持缩短的能力。虽然针对稳定负载收缩的 ASM 可以无限期地保持缩短，但针对波动负载收缩的 ASM 首先缩短，然后重新延长；这种力波动引起的再延长（FFIR）可能相当大，并且可以在药理学上进一步增强。在完整的肺中，ASM 不断受到潮式呼吸所施加的力波动的影响。该应用的关键前提是，专门针对夸大呼吸引起的 FFIR 的药物应释放 ASM 对气道腔的挤压，从而缓解支气管收缩。我们的目标是识别和评估针对这种极其有效但很大程度上未经研究的支气管扩张途径的化合物。初步研究表明，破坏肌动蛋白-肌球蛋白-肌动蛋白连接（AMAC）是增强 FFIR 的一种有吸引力的策略。在孤立的 ASM 中，减少肌动蛋白或肌球蛋白丝聚合的干预措施既可以减少 AMAC，又可以促进 FFIR。在分阶段筛选设计中，我们将使用大规模高通量初级测定来鉴定新型或已在人体中使用的化合物：1）抑制肌球蛋白聚合成粗肌丝；和/或 2) 减少人工培养的 ASM 产生的力。然后，将使用一种新颖的低通量测定来测试这些化合物中哪些化合物可以增强 FFIR 或抑制精密切割的人肺薄片内完整气道中的支气管收缩。最后，我们将通过使用 EM 断层扫描肌丝超微结构的 3D 重建来量化快速冷冻对照和药物处理的完整人类 ASM 中的肌丝长度，并通过评估药物作用的潜在替代机制来评估药物作用机制，包括改变细胞内钙动员、MLC20 磷酸化和/或 HSP27 磷酸化}}。我们的研究结果应能鉴定出可增强 FFIR 或抑制支气管收缩的治疗哮喘的新药。相关性（参见说明）：该项目的目的是确定可以通过促进支气管收缩的快速逆转而对哮喘发挥新的治疗作用的药物。这种方法与当前旨在抑制气道炎症或放松气道肌肉的治疗方法完全互补，因此，如果开发成功，应该为现有的哮喘疗法添加全新的治疗策略。