广州城区大气细颗粒物对PC-12细胞IL-8表达的影响

目的 研究广州城区大气细颗粒物(PM2.5)对PC-12细胞IL-8表达的影响,并从p38 MAPK途径探索其作用机制,促进对PM2.5毒性的认识.方法 采集广州城区大气中的PM2.5,对PC-12细胞染毒,设对照组、不同浓度PM2.5组和SB203580+PM2.5组(用20 μ mol/L的SB230580预处理1h后再给予100μg/ml的PM2.5),Trizol法提取RNA用定量PCR法检测细胞IL-8表达情况,RIRP法提取细胞总蛋白,用Western blot法检测p38 MAPK的磷酸化改变.结果 定量PCR检测显示用25、50和100μg/ml的PM2.5染毒后PC-12细胞IL-8表达明显增高;Western blot结果显示PM2.5可磷酸化激活p38 MAPK信号分子,加入p38 MAPK抑制剂SB230580可以抑制PM2.5诱导的IL-8表达.结论 PM2.5可通过p38 MAPK途径诱导PC-12细胞表达细胞因子IL-8,这可能是其导致神经细胞毒性的机制之一.

Urban PM2.5 from Guangzhou induced the expression of IL-8 in PC-12 cells

Objective To investigate the secretion ofIL-8 in PC-12 cells exposed to PM2.5 collected from Guangzhou city.Methods PM2.5 were collected from Guangzhou city.PC-12 cells were cultured in vitro and divided into several groups,namely control group,PM2.5 groups (treated with different concentration of PM2.5),and SB203580+PM2.5 group (pretreated with 20μmol/ml SB203580 followed with 100μg/ml PM2.5 exposure).Cells were incubated with PM2.5 with or without SB203580 for different times,then the expression of IL-8 was checked with real time PCR,and the phosphorylation of p38 MAPK was detected with Western blot.Results The results of RT-PCR showed that PM2.5 markedly upregulated the expression of IL-8 in PC12 cells,there was a significant difference between the control group and PM2.5 groups.It was proved by Western blot that PM2.5 increased the phosphorylation of p38 MAPK in PC-12 cells in a dosage dependent manner.Pretreated PC-12 cells with SB203580,a specific inhibitor of p38 MAPK,could significantly diminished the expression of IL-8 in PM2.5-exposed PC-12 cells.Conclusion PM2.5 can induce IL-8 secretion of PC-12 cells by upregulating the phosphorytation of p38 MAPK,which may be one of the mechanisms of PM2.5-induced neurotoxicity.