Qu Fei, Qin Xiao-Qun, Cui Yan-Ru, Xiang Yang, Tan Yu-Rong, Liu Hui-Jun, Peng Li-Hua, Zhou Xiao-Yan, Liu Chi, Zhu Xiao-Lin
Department of Physiology, Central South University Xiangya Medical School, Changsha, Hunan 410078, China.
Chem Biol Interact. 2009 May 15;179(2-3):219-26. doi: 10.1016/j.cbi.2008.10.059. Epub 2008 Nov 17.
To investigate abnormalities of cystic fibrosis transmembrane conductance regulator (CFTR) expression in chronic inflammatory airway diseases and its regulation mechanisms, the present study was designed to observe the expression of CFTR, CFTR chloride current and the possible relevant signal pathways in in vitro and in vivo bronchial epithelium by using real-time PCR, immunofluorescence, Western blot and whole cell patch-clamp. The results demonstrated that CFTR staining was decreased in rat airway epithelium under ozone stress. Ozone stress also down-regulated CFTR protein and mRNA expression and CFTR chloride current in cultured human bronchial epithelial cells (HBEC). STAT1 signal pathway was checked to investigate the signal mechanism. It was found that pretreatment with STAT1 inhibitor attenuated the down-regulated CFTR expression induced by ozone stress. We also observed that ozone stress accelerated the phosphorylation of STAT1 in HBEC, which could be influenced by some signaling molecules related to the early transduction of cellular stress. Furthermore, reactive oxygen species inhibitors N-acetylcysteine and nitric oxide synthase inhibitor aminoguanidine increased the expression of CFTR. Ozone stress could down-regulate the expression of CFTR and decrease CFTR chloride current in HBEC. The signal mechanism which referred to cascade events in cells included early oxidative stress signal transmission molecules, and subsequently transcription modulator STAT1.
为研究慢性炎症性气道疾病中囊性纤维化跨膜传导调节因子（CFTR）表达异常及其调控机制，本研究旨在通过实时定量聚合酶链反应、免疫荧光、蛋白质免疫印迹法及全细胞膜片钳技术，观察体外及体内支气管上皮细胞中CFTR的表达、CFTR氯电流及可能相关的信号通路。结果显示，臭氧应激下大鼠气道上皮细胞中CFTR染色减少。臭氧应激还下调了培养的人支气管上皮细胞（HBEC）中CFTR蛋白和mRNA表达以及CFTR氯电流。检测STAT1信号通路以研究其信号机制。发现用STAT1抑制剂预处理可减弱臭氧应激诱导的CFTR表达下调。我们还观察到臭氧应激加速了HBEC中STAT1的磷酸化，这可能受一些与细胞应激早期转导相关的信号分子影响。此外，活性氧抑制剂N-乙酰半胱氨酸和一氧化氮合酶抑制剂氨基胍可增加CFTR的表达。臭氧应激可下调HBEC中CFTR的表达并降低CFTR氯电流。细胞内涉及级联事件的信号机制包括早期氧化应激信号转导分子，随后是转录调节因子STAT1。
