石英对人胚肺成纤维细胞DNA损伤作用

Silica-induced DNA damage in human embryo lung fibroblasts

目的探讨石英粉尘对DNA及染色体的损伤作用,为尘肺病防治提供理论依据。方法标准α石英刺激人胚肺成纤维细胞(HELF),采用免疫荧光技术检测H2AX磷酸化(γH2AX)水平以及分析中性彗星实验Olive矩,作为DNA双链断裂(DSBs)损伤程度的指标,微核实验观察染色体损伤情况。结果依次用0、100、200、400μg/mL石英刺激HELF细胞,γH2AX水平呈增高趋势,半定量结果分别为(521.9±233.1)、(823.3±201.5)、(1 375.5±311.5)、(1 545.6±145.7);Olive矩亦呈增高趋势,分别为(1.74±0.24)%、(2.67±0.36)%、(9.23±0.72)%、(14.16±1.05)%,差异均有统计学意义(P<0.05)。相同剂量的石英刺激下,微核率增加,但差异无统计学意义。结论石英粉尘可引起DNA双链断裂,且存在剂量-效应关系。

Objective To study silica-induced DNA damage in human embryo lung fibroblasts（HELF） for pneumoconiosis prevention and treatment.Methods After exposed to silica,DNA double strand breaks of HELF were detected with immunofluorescence and neutral comet experiment and the micronucleus were detected with micronucleus test.Results The levels of γH2AX and Olive moments were increased significantly in dose-dependent manner after the HELF were treated with 0,100,200,and 400 μg/ml silica,with the semi-quantitative values of 521.9±233.1,823.3±201.5,1375.5±311.5,and 1545.6±145.7 and 1.74±0.24%,2.67±0.36%,9.23± 0.72%,and 14.16±1.05%,respectively.However,the micronucleus frequency was increased insignificantly compared with that of the control group.Conclusion Silica can induce DNA double strand breaks in human embryo lung fibroblasts.