Characterization of biased airway smooth muscle TAS2R agonists for treating asthma

偏向气道平滑肌 TAS2R 激动剂治疗哮喘的表征

• 批准号: 10543121
• 负责人: Stephen B Liggett
• 金额: $ 53.51万
• 依托单位: UNIVERSITY OF SOUTH FLORIDA
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-01-01 至 2024-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10543121
• 关键词: Affect; Affinity; Age; Agonist; Air Movements; Arrestins; Asthma; Back; Binding; Binding Sites; Biochemical; Biology; Bronchial Spasm; Bronchodilation; Bronchodilator Agents; Cell model; Cells; Characteristics; Clinical; Collection; Complex; Coupling; Cytometry; Data; Disease; Docking; Dose; Engineering; Ethnic Origin; Functional disorder; G-Protein-Coupled Receptors; GTP-Binding Proteins; Genetic Engineering; Human; Intervention; Learning; Libraries; Ligand Binding; Ligands; Lung; Magnetism; Methods; Modality; Modeling; Molecular Conformation; Morbidity - disease rate; Obstruction; Outcome; Pathway interactions; Patients; Pharmaceutical Preparations; Phenotype; Physiological; Physiology; Prevention; Process; Property; Public Health; Relaxation; Resistance; Signal Transduction; Slice; Smooth Muscle Myocytes; Structure; System; Tachyphylaxis; Taste Buds; Techniques; Therapeutic; Time; Transfection; Translations; Work; airway obstruction; asthmatic; attenuation; beta-arrestin; cell type; constriction; desensitization; disorder control; drug action; experience; experimental study; in silico; interest; models and simulation; molecular modeling; mortality; novel; pharmacologic; pharmacophore; predictive modeling; prevent; receptor; recruit; respiratory smooth muscle; response; simulation; three dimensional structure; treatment optimization; virtual; virtual screening

Asthma remains a major public health issue worldwide, affecting all ages and ethnicities, with 50% of patients experiencing inadequate control of the disease. Constricted airways from contraction of airway smooth muscle is the major cause of airflow obstruction, and morbidity and mortality, in asthma. Despite this key point for intervention, only one class of direct bronchodilators (-agonists) are available for treatment, and they are suboptimal for many patients. We have discovered bitter taste receptors (TAS2Rs) on human airway smooth muscle (HASM) cells which signal by a unique mechanism. When activated, TAS2Rs markedly relax HASM and relieve airway obstruction that is otherwise resistant to -agonists. However, the known TAS2R agonists have low affinity and evoke desensitization (tachyphylaxis) of the relaxation response over time via -arrestin mechanisms. The overarching hypothesis is that TAS2R agonists with novel structures can be highly effective in relaxing airways in an asthmatic milieu and yet not evoke tachyphylaxis. The broad long-term objectives are to determine the 3D structures and binding sites of two TAS2Rs expressed on HASM (R5 and R14) and then use these structures to perform virtual docking of an agnostic ultra-large compound library to identify potential ligands. These hits will be examined in engineered model cells, but will be most intensely studied within the context of the physiology of HASM cells, and human airways, under asthmatic conditions to delineate novel ways to engage the receptor that are biased towards relaxation and away from desensitization. Aim 1 will computationally determine the structures and binding sites for R5 and R14 using methods that include 13 trillion combinations of the residues to determine favorable energy conformations of inactive and active states. The structures will be used to dock compounds from a highly diverse library. These will be studied in Aim 2 to determine potency and efficacy in genetically engineered model cells and in HASM cells from nonasthmatic and asthmatic lungs. In Aim 3, the most favorable compounds will be studied to ascertain -arrestin engagement and biasing away from desensitization in model cells, HASM cells, and human lungs under asthmatic conditions. Results from Aims2/3 will be fed back into Aim1 to further refine a model of biased agonists for these HASM TAS2Rs. Based on our preliminary data that support all three Aims, we will learn about the structural requirements for biasing for these receptors. And, we anticipate that multiple highly effective agonists with unexpected structures will be identified and that their bronchodilating properties in asthma will represent a new class of powerful non-desensitizing agents for treating and preventing bronchospasm.

哮喘仍然是全球一个主要的公共卫生问题，影响了所有年龄和种族，其中50％的患者 疾病的控制不足。气道平滑肌收缩的狭窄气道 是哮喘中气流异议以及发病率和死亡率的主要原因。尽管有这个关键点 干预措施，只有一类直接支气管扩张剂（激动剂）可以进行治疗，它们是 许多患者的次优。我们在人类气道上发现了苦味受体（TAS2R） 肌肉（HASM）细胞通过独特的机制发出信号。激活时，tas2rs明显放松了hasm和 缓解气道反对意见，原本对激动剂具有抵抗力。但是，已知的TAS2R激动剂具有 随着时间的流逝，松弛响应的低亲和力和唤起脱敏（速度）通过-arrestin 机制。总体假设是具有新结构的Tas2r激动剂可以非常有效 在哮喘环境中放松气道，但没有引起速度。广泛的长期目标是 确定两个在HASM（R5和R14）上表达的TAS2R的3D结构和结合位点，然后 使用这些结构来执行不可知论超大化合物库的虚拟对接以识别潜力 配体。这些命中将在工程模型单元格中进行检查，但最积极地研究了 在哮喘条件下，HASM细胞和人类气道生理学的背景来描述新颖的方式 让接收器偏向放松并远离脱敏。目标1意志 使用包括13万亿的方法来确定R5和R14的结构和结合位点 残差的组合，以确定非活性和活性状态的有利能量构象。这 结构将用于从高度多样化的库中进行对接化合物。这些将在目标2中研究 确定一般工程模型细胞的效力和有效性，以及来自非asthmatic和 哮喘肺。在AIM 3中，最有利的化合物将研究以确定-arrestin参与度 并在哮喘条件下偏离模型细胞，HASM细胞和人肺的脱敏。 AIMS2/3的结果将被馈回AIM1，以进一步完善这些HASM的偏见激动剂模型 tas2rs。基于我们支持这三个目标的初步数据，我们将了解结构性 这些受体偏见的要求。而且，我们预计有多种高效激动剂与 将确定意外结构，并认为其哮喘中的支气管扩张特性代表一个新的 一类强大的非敏感剂用于治疗和预防支气管痉挛。