Park Il-Ho, Kang Ju-Hyung, Kim Jin Ah, Shin Jae-Min, Lee Heung-Man
Department of Otorhinolaryngology, Head and Neck Surgery, Guro Hospital, Korea University College of Medicine, Seoul, South Korea.
Int Arch Allergy Immunol. 2016;171(3-4):209-216. doi: 10.1159/000453033. Epub 2017 Jan 4.
Diesel exhaust particles (DEPs), the major contributors to air pollution, induce inflammatory responses in the nasal epithelium. Overproduction of airway mucins is an important pathogenic finding in inflammatory airway diseases.
The aims of the present study were to determine the effect of DEPs on the expression of the mucin gene MUC4 and to investigate the underlying mechanism of DEP-induced MUC4 expression in NCI-H292 cells and primary nasal epithelial cells (PNECs).
NCI-H292 cells were stimulated for 24 h with DEPs. Messenger RNA (mRNA) and protein expression of MUC4 was determined by real-time reverse transcription (RT) polymerase chain reaction (PCR) and Western blotting. NCI-H292 cells were exposed to 3 mitogen-activated protein kinase inhibitors (U0126, SB203580, and SP600125) and a CREB (cAMP response element-binding protein) inhibitor prior to stimulation with DEPs, and MUC4 expression was examined by RT-PCR and Western blotting. PNECs were pretreated with a p38 inhibitor and CREB inhibitor prior to stimulation with DEPs, and MUC4 expression was then determined by RT-PCR and/or Western blotting.
DEPs significantly increased the expression of MUC4 mRNA and protein. MUC4 mRNA and protein expression was inhibited by pretreatment with p38 and CREB inhibitors in NCI-H292 stimulated with DEPs. p38 and CREB inhibitors also blocked the expression of MUC4 mRNA and protein in DEP-stimulated PNECs.
We demonstrated that DEPs stimulated the expression of MUC4 via the p38/CREB pathway in NCI-H292 cells and PNECs. The results of the present study pave the way for further studies on the role of MUC4 in DEP-induced hypersecretion in airway epithelium.
柴油尾气颗粒（DEPs）是空气污染的主要来源，可诱导鼻上皮细胞发生炎症反应。气道粘蛋白过度产生是炎症性气道疾病的一项重要致病特征。
本研究旨在确定DEPs对粘蛋白基因MUC4表达的影响，并探究DEPs诱导NCI-H292细胞和原代鼻上皮细胞（PNECs）中MUC4表达的潜在机制。
用DEPs刺激NCI-H292细胞24小时。通过实时逆转录（RT）聚合酶链反应（PCR）和蛋白质印迹法测定MUC4的信使核糖核酸（mRNA）和蛋白质表达。在用DEPs刺激之前，将NCI-H292细胞暴露于3种丝裂原活化蛋白激酶抑制剂（U0126、SB203580和SP600125）和一种环磷腺苷效应元件结合蛋白（CREB）抑制剂中，然后通过RT-PCR和蛋白质印迹法检测MUC4的表达。在用DEPs刺激之前，用p38抑制剂和CREB抑制剂预处理PNECs，然后通过RT-PCR和/或蛋白质印迹法测定MUC4的表达。
DEPs显著增加了MUC4 mRNA和蛋白质的表达。在用DEPs刺激的NCI-H292细胞中，用p38和CREB抑制剂预处理可抑制MUC4 mRNA和蛋白质的表达。p38和CREB抑制剂也可阻断DEPs刺激的PNECs中MUC4 mRNA和蛋白质的表达。
我们证明，DEPs通过p38/CREB途径刺激NCI-H292细胞和PNECs中MUC4的表达。本研究结果为进一步研究MUC4在DEPs诱导的气道上皮细胞分泌亢进中的作用铺平了道路。
