Knobloch Jürgen, Yanik Sarah Derya, Körber Sandra, Stoelben Erich, Jungck David, Koch Andrea
Medical Clinic III for Pneumology, Allergology, Sleep- and Respiratory Medicine, Bergmannsheil University Hospital, Bochum, Germany.
Medical Clinic III for Pneumology, Allergology, Sleep- and Respiratory Medicine, Bergmannsheil University Hospital, Bochum, Germany.
Biochem Pharmacol. 2016 Sep 15;116:188-99. doi: 10.1016/j.bcp.2016.07.008. Epub 2016 Jul 12.
Pathological proliferation of human airway smooth muscle cells (HASMCs) causes hyperplasia in chronic lung diseases. Signaling pathways that link airway inflammation to HASMC proliferation might provide therapeutic targets for the prevention of airway remodeling and chronic lung diseases. Endothelin-1 (ET-1) signals via endothelin-A- and B-receptors (ETAR, ETBR) to perpetuate HASMC-associated and TNFα-dependent inflammatory processes.
endothelin receptor antagonists (ERAs) suppress HASMC proliferation induced by inflammatory cytokines. HASMCs were stimulated ex vivo with cytokines in the presence or absence of ERAs (ETAR-specific/selective: BQ123, ambrisentan; ETBR-specific: BQ788; non-selective: bosentan, macitentan, ACT-132577) or cytokine-blocking antibodies. Cell counts, DNA-synthesis (BrdU-incorporation assay), cytokine production (ELISA) and ETBR expression (whole-genome microarray data, western blot) were analyzed. ET-1-induced HASMC proliferation and DNA-synthesis were reduced by protein kinase inhibitors and ETAR-specific/selective ERAs but not by BQ788. TNFα-induced HASMC proliferation and DNA-synthesis were reduced by all ERAs. TNFα induced ET-1 and ETBR expression. TNFα- and ET-1-induced GM-CSF releases were both reduced by BQ123 and BQ788. TNFα- and ET-1-induced IL-6 releases were both reduced by BQ123 but not by BQ788. Combined but not single blockade of GM-CSF-receptor-α-chain and IL-6 reduced TNFα- and ET-1-induced HASMC proliferation and DNA-synthesis. Combined but not single treatment with GM-CSF and IL-6 induced HASMC proliferation and DNA-synthesis in the presence of ET-1. In conclusion, TNFα induces HASMC proliferation via ET-1/GM-CSF/IL-6. ETBR requires up-regulation by TNFα to mediate ET-1 effects on HASMC proliferation. This signaling cascade links airway inflammation to HASMC-associated remodeling processes and is sensitive to ERAs. Therefore, ERAs could prevent inflammation-induced airway smooth muscle hyperplasia.
人气道平滑肌细胞（HASMCs）的病理性增殖会导致慢性肺部疾病中的增生。将气道炎症与HASMC增殖联系起来的信号通路可能为预防气道重塑和慢性肺部疾病提供治疗靶点。内皮素-1（ET-1）通过内皮素A和B受体（ETAR、ETBR）发出信号，使与HASMC相关的和TNFα依赖性炎症过程持续存在。
内皮素受体拮抗剂（ERAs）可抑制炎性细胞因子诱导的HASMC增殖。在有或没有ERAs（ETAR特异性/选择性：BQ123、安立生坦；ETBR特异性：BQ788；非选择性：波生坦、马西替坦、ACT-132577）或细胞因子阻断抗体的情况下，用细胞因子对HASMCs进行体外刺激。分析细胞计数、DNA合成（BrdU掺入试验）、细胞因子产生（ELISA）和ETBR表达（全基因组微阵列数据、蛋白质印迹）。蛋白激酶抑制剂和ETAR特异性/选择性ERAs可降低ET-1诱导的HASMC增殖和DNA合成，但BQ788不能。所有ERAs均可降低TNFα诱导的HASMC增殖和DNA合成。TNFα诱导ET-1和ETBR表达。BQ123和BQ788均可降低TNFα和ET-1诱导的GM-CSF释放。BQ123可降低TNFα和ET-1诱导的IL-6释放，但BQ788不能。联合阻断GM-CSF受体α链和IL-6可降低TNFα和ET-1诱导的HASMC增殖和DNA合成，但单一阻断无效。在ET-1存在的情况下，联合使用GM-CSF和IL-6而非单一治疗可诱导HASMC增殖和DNA合成。总之，TNFα通过ET-1/GM-CSF/IL-6诱导HASMC增殖。ETBR需要TNFα上调才能介导ET-1对HASMC增殖的作用。这种信号级联将气道炎症与HASMC相关的重塑过程联系起来，并且对ERAs敏感。因此，ERAs可预防炎症诱导的气道平滑肌增生。
