Issa Razao, Xie Shaoping, Lee Kang-Yun, Stanbridge Rex D, Bhavsar Pankaj, Sukkar Maria B, Chung Kian Fan
National Heart and Lung Institute, Imperial College, Dovehouse St., London SW3 6LY, UK.
Am J Physiol Lung Cell Mol Physiol. 2006 Jul;291(1):L66-74. doi: 10.1152/ajplung.00384.2005. Epub 2006 Apr 14.
Airway smooth muscle cells (ASMC) are a source of inflammatory chemokines that may propagate airway inflammatory responses. We investigated the production of the CXC chemokine growth-related oncogene protein-alpha (GRO-alpha) from ASMC induced by cytokines and the role of MAPK and NF-kappaB pathways. ASMC were cultured from human airways, grown to confluence, and exposed to cytokines IL-1beta and TNF-alpha after growth arrest. GRO-alpha release, measured by ELISA, was increased by >50-fold after IL-1beta (0.1 ng/ml) or 5-fold after TNF-alpha (1 ng/ml) in a dose- and time-dependent manner. GRO-alpha release was not affected by the T helper type 2 cytokines IL-4, IL-10, and IL-13. IL-1beta and TNF-alpha also induced GRO-alpha mRNA expression. Supernatants from IL-1beta-stimulated ASMC were chemotactic for neutrophils; this effect was inhibited by anti-GRO-alpha blocking antibody. AS-602868, an inhibitor of IKK-2, and PD-98059, an inhibitor of ERK, inhibited GRO-alpha release and mRNA expression, whereas SP-600125, an inhibitor of JNK, reduced GRO-alpha release without effect on mRNA expression. SB-203580, an inhibitor of p38 MAPK, had no effect. AS-602868 but not PD-98059 or SP-600125 inhibited p65 DNA-binding induced by IL-1beta and TNF-alpha. By chromatin immunoprecipitation assay, IL-1beta and TNF-alpha enhanced p65 binding to the GRO-alpha promoter, which was inhibited by AS-602868. IL-1beta- and TNF-alpha-stimulated expression of GRO-alpha from ASMC is regulated by independent pathways involving NF-kappaB activation and ERK and JNK pathways. GRO-alpha released from ASMC participates in neutrophil chemotaxis.
气道平滑肌细胞（ASMC）是炎症趋化因子的一个来源，可能会传播气道炎症反应。我们研究了细胞因子诱导ASMC产生CXC趋化因子生长相关癌基因蛋白α（GRO-α）的情况以及丝裂原活化蛋白激酶（MAPK）和核因子κB（NF-κB）信号通路的作用。从人气道培养ASMC，使其生长至汇合，生长停滞后用细胞因子白细胞介素-1β（IL-1β）和肿瘤坏死因子-α（TNF-α）处理。通过酶联免疫吸附测定（ELISA）测量，GRO-α释放量在IL-1β（0.1纳克/毫升）作用后增加了50多倍，在TNF-α（1纳克/毫升）作用后增加了5倍，呈剂量和时间依赖性。GRO-α释放不受2型辅助性T细胞细胞因子IL-4、IL-10和IL-13的影响。IL-1β和TNF-α也诱导GRO-α信使核糖核酸（mRNA）表达。IL-1β刺激的ASMC的上清液对中性粒细胞有趋化作用；这种作用被抗GRO-α阻断抗体抑制。IKK-2抑制剂AS-602868和细胞外信号调节激酶（ERK）抑制剂PD-98059抑制GRO-α释放和mRNA表达，而应激活化蛋白激酶（JNK）抑制剂SP-600125减少GRO-α释放但对mRNA表达无影响。p38 MAPK抑制剂SB-203580无作用。AS-602868而非PD-98059或SP-600125抑制IL-1β和TNF-α诱导的p65与DNA结合。通过染色质免疫沉淀测定，IL-1β和TNF-α增强p65与GRO-α启动子的结合，这被AS-602868抑制。IL-1β和TNF-α刺激ASMC表达GRO-α受涉及NF-κB激活以及ERK和JNK信号通路的独立途径调控。ASMC释放的GRO-α参与中性粒细胞趋化。
