Pulmonary Cell Research and Pneumology, Department Biomedicine & Internal Medicine, University & University Hospital Basel, Petersgraben 4, CH-4031, Basel, Switzerland; Department of Medicine and Division of Pulmonary and Critical Care Medicine, Jishuitan Hospital, Fourth Medical College of Peking Medical University, No 31, Xinjiekou East Street, Xicheng District, Beijing, China.
Pulmonary Cell Research and Pneumology, Department Biomedicine & Internal Medicine, University & University Hospital Basel, Petersgraben 4, CH-4031, Basel, Switzerland.
Pulm Pharmacol Ther. 2019 Jun;56:20-28. doi: 10.1016/j.pupt.2019.03.005. Epub 2019 Mar 12.
Airway smooth muscle cell (ASMC) hyperplasia causes airway wall remodelling, which is resisting to therapy. Long acting β2-agonists (LABA) relax airway muscles, but their effect on remodelling is unclear. This study compared the anti-proliferative effect of LABA in human primary ASMC, in situations where LABA were applied before, together, or after platelet derived growth factor (PDGF-BB). Cells obtained from controls (n = 5), and asthma patients (n = 5) were stimulated by PDGF-BB (10 ng/ml) before or after the application of formoterol or salmeterol. Proliferation was determined by direct cell counts over three days, cell cycle control proteins p21, p27, signalling proteins Erk1/2 and p38 mitogen activated protein kinase (MAPK) were detected by immuno-blotting. PDGF-BB induced proliferation was significantly stronger in asthmatic ASMC versus controls. Proliferation was prevented by 30 min pre-incubation with LABA. When LABA were applied together or after PDGF-BB, their anti-proliferative effect was no longer significant. In untreated ASMC, LABA increased the expression of p21 and p27 through cAMP, and this mechanism was abolished by the presence of PDGF-BB. The data show that the anti-proliferative effect of cAMP signalling cannot overcome the mitogenic signalling cascade once it was activated. Therefore, remodelling in asthma cannot be reduced by LABA.
气道平滑肌细胞（ASMC）增生导致气道壁重塑，这是对抗治疗的。长效β2-激动剂（LABA）可使气道肌肉松弛，但它们对重塑的影响尚不清楚。本研究比较了 LABA 在人原代 ASMC 中的抗增殖作用，在 LABA 分别在 PDGF-BB 之前、同时或之后应用的情况下。从对照者（n=5）和哮喘患者（n=5）中获得的细胞，在 PDGF-BB（10ng/ml）刺激之前或之后应用福莫特罗或沙美特罗。通过直接细胞计数在三天内确定增殖，通过免疫印迹检测细胞周期控制蛋白 p21、p27、信号蛋白 Erk1/2 和 p38 丝裂原激活蛋白激酶（MAPK）。与对照者相比，PDGF-BB 诱导的增殖在哮喘 ASMC 中明显更强。30 分钟的 LABA 预孵育可预防增殖。当 LABA 同时或在 PDGF-BB 之后应用时，其抗增殖作用不再显著。在未处理的 ASMC 中，LABA 通过 cAMP 增加 p21 和 p27 的表达，而 PDGF-BB 的存在则消除了这种机制。数据表明，一旦 cAMP 信号的促有丝分裂信号级联被激活，cAMP 信号的抗增殖作用就无法克服。因此，哮喘中的重塑不能通过 LABA 来减轻。
