1-硝基芘和苯并[a]芘对人肺上皮A549细胞的联合细胞毒性

Combined effects of 1-nitropyrene and benzo(a)pyrene on cytotoxicity and DNA damage in human lung epithelial A549 cells

1-硝基芘(1-nitropyrene,1-NP)是柴油车尾气中检测浓度最高的硝基多环芳烃.以1-NP为主体,人肺上皮A549细胞为研究对象,探讨了1-NP和苯并[a]芘(benzo(a)pyrene,B[a]p)的联合细胞毒性及其对DNA的损伤.联合染毒实验结果表明:当B[a]p和1-NP同时作用于A549细胞时,B[a]p能明显减弱由1-NP造成的细胞增殖抑制和细胞内活性氧簇(reactive oxygen species,ROS)水平升高,但对DNA的损伤与1-NP单独染毒组相近;利用B[a]p预染毒A549细胞24 h,能明显减弱由1-NP造成的细胞增殖抑制和ROS水平升高,但对DNA的损伤加剧.以上结果说明,1-NP和B[a]p联合作用可能是通过抑制ROS的生成来降低对细胞增殖的抑制,但所造成的对DNA损伤的加剧可能是通过其他的作用途径.

Using human lung epithelial A549 cells, combined toxic effects of 1-nitropyrene （1-NP） and benzo（a）pyrene （B[a]p） were evaluated. The 1-NP caused a significantly concentration-dependent viability decrease, DNA damage and reactive oxygen species （ROS） generation. Compared with the groups treated with 1-NP alone, viability was significantly increased and ROS generation was significantly reduced in combined-treated groups with 1-NP and B[a]p. However, the DNA damage was significantly increased in the combined- treated groups compared with the groups treated with 1-NP alone. These results suggested that 1-NP may mediate the cytotoxic effects through ROS generation, and pretreatment, with B[a]p may inhibit ROS generation induced by 1-NP, and thereby reducing the cell death in A549 cells. However mechanisms of DNA damage deserves further investigations.