Abstract：
Chronic airway inflammation induced by cigarette smoke (CS) plays an essential role in the pathogenesis of chronic obstructive pulmonary disease (COPD). MALAT1 is involved in a variety of inflammatory disorders. However, studies focusing on the interaction between MALAT1 and CS-induced airway inflammation remain unknown. The present study investigated the effects and mechanisms of MALAT1 in CS-induced airway inflammation in the pathogenesis of COPD. RT-qPCR was employed to determine the mRNA levels of MALAT1, miR-30a-5p and inflammatory cytokines. Protein concentrations of IL-1β and IL-6 in cell culture supernatant and mouse bronchoalveolar lavage fluid (BALF) were assessed by ELISA assay kits. Dual-luciferase reporter assay was conducted to verify the interaction between MALAT1 and miR-30a-5p. The protein expression of JNK and p-JNK was determined by western blot (WB). MALAT1 was highly expressed in cigarette smoke extract (CSE)-treated human bronchial epithelial cells (HBECs) and COPD mice lung tissues. Knockdown of MALAT1 significantly alleviate CS-induced inflammatory response. MALAT1 directly interacted with miR-30a-5p and knockdown of miR-30a-5p significantly inhibit the protective effects of MALAT1 silencing after CS exposure. Additionally, our results showed that miR-30a-5p could regulate inflammation via modulating the activation of JNK signaling pathway. Moreover, our results demonstrated MALAT1 could activate JNK signaling pathway by sponging miR-30a-5p. Our results demonstrated MALAT1 promotes CS-induced airway inflammation by inhibiting the activation of JNK signaling pathway via sponging miR-30a-5p.
摘要：
香烟烟雾（CS）引起的慢性气道炎症在慢性阻塞性肺疾病（COPD）的发病机制中起着至关重要的作用。MALAT1与多种炎症性疾病有关。然而,关于MALAT1和CS诱导的气道炎症之间相互作用的研究仍然未知。本研究探讨了MALAT1在CS诱导的气道炎症中的作用及其机制。采用RT-qPCR测定MALAT1、miR-30a-5p和炎性细胞因子的mRNA水平。通过ELISA测定试剂盒评估细胞培养上清液和小鼠支气管肺泡灌洗液（BALF）中IL-1β和IL-6的蛋白浓度。进行双荧光素酶报告基因测定以验证MALAT1和miR-30a-5p之间的相互作用。通过蛋白质印迹(WB)测定JNK和p-JNK的蛋白表达。MALAT1在香烟烟雾提取物（CSE）处理的人支气管上皮细胞（HBEC）和COPD小鼠肺组织中高表达。MALAT1的敲除显著减轻CS诱导的炎症反应。MALAT1直接与miR-30a-5p相互作用，敲低miR-30a-5p显著抑制CS暴露后MALAT1沉默的保护作用。此外,我们的结果显示miR-30a-5p可以通过调节JNK信号通路的激活来调节炎症.此外，我们的结果表明MALAT1可以通过激活miR-30a-5p激活JNK信号通路.我们的结果表明MALAT1通过抑制miR-30a-5p激活JNK信号通路促进CS诱导的气道炎症。
