铀矿尘对人正常支气管上皮细胞株细胞凋亡相关蛋白表达的影响

Effects of uranium dust on expression levels of apoptosis-related protein in human bronchial epithelial cells

目的探讨铀矿尘对人正常支气管上皮细胞株HBE细胞凋亡相关蛋白表达的影响及凋亡的可能机制。方法体外培养HBE细胞,分为对照组、铀矿尘组（12.5、25、50、100、200μg/ml）。细胞染毒12 h后,用MTT法检测HBE细胞存活率,流式细胞仪检测细胞凋亡率,免疫组化法检测凋亡相关蛋白B细胞淋巴瘤/白血病-2（Bcl-2）蛋白、Bcl-2相关X蛋白（Bax）及细胞色素C（CytC）、半胱天冬酶-3（caspase-3）和半胱天冬酶-9（caspase-9）的蛋白表达。结果当铀矿尘浓度为25~200μg/ml时,HBE细胞存活率均低于对照组,细胞凋亡率和坏死率均高于对照组,差异均有统计学意义（P〈0.01）。随着铀矿尘浓度的升高,HBE细胞Bax、Bcl-2、CytC、caspase-3、caspase-9蛋白表达量逐渐增加,均高于对照组,差异均有统计学意义（P〈0.05或P〈0.01）。结论铀矿尘对HBE细胞的凋亡作用可能是通过线粒体途径实现的。

Objective To understand the apoptosis mechanisms of human bronchial epithelial （HBE） cell induced by uranium dust. Methods HBE cells were divided into two groups： control group and uranium dust exposure groups （12.5, 25, 50, 100 and 200 μg/ml）. After 12 h of incubation, cytotoxicity was tested with MTr assay. Cell apoptosis ratio was measured with flow cytometer and the expression of mitochondrial pathway related apoptosis proteins were detected by immunocytochemistry. Results With the increase of uranium dust exposure level, the survival rate of HBE cells decreased and apoptosis ratio increased. The expression of Bcl-2, Bax, caspase-3 and caspase-9 increased with the increase of uranium dust exposure. Conclusion Uranium dust can induce HBE cells apoptosis and a mitochondrial-related pathway may be involved.