中文摘要：

目的探讨茶黄素对炎症反应时气道上皮细胞黏液分泌的影响。方法通过人中性粒细胞弹性蛋白酶（HNE）刺激人肺腺癌细胞A549，构建炎症反应时气道黏液高分泌模型，以茶黄素和表皮生长因子受体（EGFR）阻断剂表皮生长因子受体阻断剂（AG1478）进行干预，观察黏蛋白5AC（MUC5AC）、EGFR、磷酸化EGFR（P-EGFR）、磷酸化细胞外信号调节激酶1／2（P-ERK1／2）、兔抗磷酸化p38（P-p38）及磷酸化JNK丝裂原活化蛋白激酶（P-JNK）的表达。用四甲基偶氮唑盐法测定细胞活性，再将A549细胞分为对照组、HNE处理组、茶黄素组、AG1478组和茶黄素＋AG1478组。用逆转录PCR方法检测各组MUC5AC mRNA、EGFR mRNA的变化；Western blot法检测EGFR、P-EGFR、P-ERK1／2、P-p38和P-JNK蛋白的表达；酶联免疫吸附测定法观察MUC5AC蛋白表达的变化，并用细胞免疫激光共聚焦显微镜观察作用前后黏蛋白的分布。两样本均数间比较采用t检验，多样本均数间比较采用单因素方差分析。结果HNE处理组MUC5AC的mRNA和蛋白的积分吸光度值分别为0．99±0．03和（169±6）μg／mg，EGFR mRNA和蛋白表达的积分吸光度值分别为0．98±0．02和（0．89±0．03）μg/mg，均较对照组[0．53±0．02、（105±4）μg／mg和0．61±0．11、0．21±0．05]明显升高；P-EGFR、P-ERK1／2的蛋白表达也较对照组显著增加，而P-p38的表达则有较低幅度的增强，P-JNK无明显变化。给予茶黄素及AG1478预处理后，与HNE刺激组相比，EGFR、P-EGFR、P-ERK1／2、P-p38均明显下调，P-JNK无相应改变；而茶黄素＋AG1478组MUC5AC mRNA和MUC5AC的下调较单独用茶黄素或AG1478处理更为明显，其积分吸光度值分别为0．20±0．02和（125±3）μg／mg，差异均有统计学意义（t值分别为3．02和1405．94，均P〈0．05）。结论茶黄素可通过下调EGFR水平、减少EGFR的活化、部分阻遏EGFR信号转导途径及细胞外信

英文摘要：

Objective To investigate the effects of theaflavins （TFs） on airway mucous hypersecretion and on the signal transduction pathway of epidermal growth factor receptor （EGFR）. Methods The cell model of mucous hypersecretion was made by human lung A549 cell stimulated by human neutrophil elastae （HNE）, and treated with TFs and AG1478, a blocking agent of EGFR. The expression of mucin （MUC） 5AC, EGFR, P-EGFR, phosphorylation extracellular signal regulated kinase 1/2 （P-ERKI/2）, P- p38, phosphorylation c-Jun N-terminal kinase （P-JNK） were detected. The cell activity after TFs treatment was assessed by methyl thiazolyl tetrazolium method. The cells were divided into 5 groups ： a negative control group, an HNE treatment group, a TFs pre-treatment group, an AG1478 pre-treatment group and a TFs ＋ AG1478 group. The changes of MUC5AC mRNA and EGFR mRNA were examined by the use of reverse transcriptase-polymerase chain reaction （RT-PCR）. The protein expression changes of EGFR, P-EGFR, P- ERK1/2, P-p38 and P-JNK were measured by Western blot. The protein expression changes of MUC5AC were detected by enzyme-linked immunosorbeut assay, while the protein morphological changes of MUC5AC were observed by immunofluorescence and confocal laser technology. The data were analyzed with SPSS 12.0 software. Differences between groups were assessed for significance by t test. Results The expression levels of MUC5AC mRNA and its protein in the HNE group were （0.99±0. 03）and（169±6） μg/mg, and those of EGFR were （0. 98 ±0. 02） and （0. 89± 0. 03）, both of them increased significantly as compared to those in the control group [ （0. 53±0. 02）, （105±4） μg/mg and （0. 61±0. 11 ）, （0. 21±0.05）].The protein expressions of P-EGFR, P-ERK1/2, P-ERK1/2 were increased significantly as compared with the control group. But the increase of P-p38 was not significant as compared to P-ERK1/2. The protein expression of P-JNK did not change markedly. After the cells were pre-treated with TF