Macrophage Immunometabolism alteration by intense beta agonist therapy.

摘要 使用β受体激动剂作为支气管扩张剂治疗哮喘可有效靶向气道 平滑肌细胞逆转支气管收缩和缓解呼吸困难，然而， 使用这些药物长期高剂量治疗的非预期和未被认识的副作用可能 肺泡巨噬细胞代谢的紊乱对宿主防御产生不利影响 或组织健康。我们在肺泡巨噬细胞中发现了一个独特的基因表达特征 这表明在患有糖尿病的人中，通用细胞激活剂环腺苷酸（cAMP）受到抑制， 使用大剂量长效β受体激动剂治疗重度哮喘。细胞机制 研究表明，用β-CD对人巨噬细胞或单核细胞进行急性治疗， 激动剂异丙肾上腺素通过腺苷酸环化酶（AC）诱导快速cAMP合成。然而，在这方面， 这些细胞在过夜暴露后变得对异丙肾上腺素不敏感。脱敏 导致它们不能产生cAMP， 激活其分子靶蛋白激酶A。长期暴露于β受体激动剂会导致 巨噬细胞转录组学表型紊乱，PKA基因受到抑制， 激活CREB/CREM网络，并模仿哮喘患者中发现的基因签名。 患者队列。在单细胞分析中，单核细胞比肺泡 巨噬细胞其他基因表达的变化包括参与细胞凋亡的途径。 代谢如糖酵解和脂质代谢。cAMP-PKA的β激动剂抑制 信号传导导致这些巨噬细胞变得代谢静止， 糖酵解和氧化磷酸化。mTOR蛋白的激活被抑制， 延长β激动剂暴露，限制对LPS的糖酵解反应，这是重要的 病原体的反应。同样，β-激动剂诱导代谢静止， 巨噬细胞削弱其有效吞噬细菌颗粒或清除活细菌的能力 从一个共同文化的模式。用β受体激动剂沙美特罗治疗的小鼠表现出迟缓， 巨噬细胞对细菌的反应或LPS诱导糖酵解。这些观察结果 提示肺泡巨噬细胞性能和宿主防御反应可能是有限的 在使用慢性高剂量β受体激动剂的患者中， 用于肺部疾病的处方药。本申请旨在探讨机制， 强烈的β激动剂暴露对巨噬细胞性能的影响， 告知处方实践或导致新的替代疗法的最终开发。

ABSTRACT The use of beta agonists as bronchodilator therapy for asthma effectively targets airway smooth muscle cells to reverse bronchoconstriction and relieve breathlessness, however an unintended and unrecognized side effect of chronic high dose therapy with these drugs may be that derangement of alveolar macrophage metabolism adversely impacts host defense or tissue health. We identify a unique gene expression signature in alveolar macrophages indicating suppression of the universal cell activator cyclic AMP (cAMP) in persons with severe asthma treated with high dose and long acting beta agonists. Cellular mechanistic studies reveal that acute treatment of human macrophages or monocytic cells with the beta agonist Isoproterenol induces rapid cAMP synthesis by adenylyl cyclase (AC). However, these cells become desensitized to isoproterenol after overnight exposure. Desensitization of these monocytes causes them to fail to generate cAMP with corresponding failure to activate its molecular target Protein Kinase A. Prolonged beta agonist exposure causes a deranged transcriptomic phenotype of macrophages with suppression of genes in the PKA- activated CREB/CREM network and mimics the gene signature discovered in the asthmatic patient cohort. In single cell analysis, monocytes are more impacted than alveolar macrophages. Other gene expression changes include pathways involved in cell metabolism like glycolysis and lipid metabolism. Beta agonist suppression of cAMP-PKA signaling causes these macrophages to become metabolically quiescent with decreased glycolysis and oxidative phosphorylation. Activation of the mTOR protein is suppressed by prolonged beta agonist exposure, limiting the glycolytic response to LPS, which is important for pathogen responses. Likewise, beta-agonist induced metabolic quiescence in macrophages impairs their ability to effectively engulf bacterial particles or clear live bacteria from a co-culture model. Mice treated with the beta agonist salmeterol show sluggish macrophage responses to bacteria or LPS induction of glycolysis. These observations suggest that alveolar macrophage performance and host defense responses may be limited in patients using chronic high dose beta agonists, which are among the most commonly prescribed agents for lung disease. This application seeks to explore the mechanism and consequences of intense beta agonist exposure on macrophage performance, which may inform prescribing practice or lead to the eventual development of new alternate therapies.