中文摘要：

目的研究煤焦沥青烟提取物对BEAS-2B细胞Nrf2、Keap1、NQO1的基因及其蛋白表达的影响,以探讨煤焦沥青烟提取物在造成细胞氧化损伤过程中Nrf2-Keap1/ARE通路的作用机制。方法设立未处理对照组、0.1%DMSO溶剂对照组、5μg/ml B（a）P阳性对照组、6μmol/L全反式维甲酸组、6μmol/L全反式维甲酸预处理0.5 h后5μg/ml CTP染毒组和CTP染毒组（1、5、10和20μg/ml）,染毒3、6、12和24 h后提取总RNA;RT-PCR检测Nrf2、Keap1、NQO1 mRNA的相对表达量;Western blot测定Nrf2、Keap1、NQO1蛋白的相对表达量。结果不同CTP染毒剂量作用后各个基因mRNA相对表达量差异无统计学意义（P〉0.05）,而不同时间点相对表达量差异有统计学意义（P〈0.05）。Western blot结果显示,随着CTP烟提取物染毒浓度的增加,Keap1蛋白无明显变化,NQO1蛋白表达量逐渐上升;Nrf2蛋白在5μg/ml染毒浓度时表达最高,在5μg/ml CTP染毒浓度作用下,BEAS-2B细胞Nrf2蛋白表达量随时间逐渐升高,在染毒6 h后达到最高,之后表达量又呈下降趋势。结论煤焦沥青烟提取物作用于BEAS-2B细胞后,代谢酶NQO1表达上调,推测Keap1-Nrf2/ARE通路可能通过上调细胞保护性基因NQO1的表达而对抗煤焦沥青毒性作用,降低细胞氧化损伤。

英文摘要：

Objective To study the effect of coal tar pitch（CTP） extract on the expressions of Nrf2,Keapl,NQ01 mRNA, and to explore the mechanism of Nrf2-Keapl/ARE pathway in the process of cell oxidative damage caused by CTP. Methods The control group with 0.1% DMSO, the blank control group, 5 μg / ml B （a） P positive control group, 6μmol / L atl-trans retinoic acid group, the 5 μg/ ml CTP group after pretreatment with 6 μmol / L ATRA for 0. 5h and the CTP group （ 1, 5, 10 and 20 μg/ml） were set up. BEAS-2B cells were treated with CTP and total cell RNA in BEAS-2B cells were extracted at 3, 6, 12 and 24 h by CTP treated. The reverse transcription polymerase chain reaction（RT-PCR） was applied to measure the expressions of Nrf2,Keapl and NQ01 mRNA, and Western blot was used to determine the level of Nrf2,Keapl and NQO1 protein. Results There were statistically significant differences in the relative mRNA level of each gene at different time points instead of different doses of CTP extract. Western blot results showed that there was nothing apparent of Keapl protein changes by increasing the concentration of CTP extract, but the expression of NQ01 protein was increased gradually. The level of Nrf2 proteins was highest at 5 μg/ml of CTP extract among the test groups, and that of Nrf2 protein was highest for 6 h among time points. Conclusion The expression of NQ01 was up-regulated in BEAS-2B cells induced by CTP extract. It is shown that Keapl-Nrf2/ARE pathway may up-regulate cellular protective gene to antagonize the toxicity of CTP.