为了探讨甲醛对人肝癌细胞HepG2的遗传毒性效应,该实验以体外培养的HepG2细胞作为实验材料,运用单细胞凝胶电泳(SCGE)技术分析不同浓度甲醛处理2 h后HepG2细胞DNA损伤效应.结果显示,低浓度(5,25μmol/L)甲醛处理后HepG2细胞尾部DNA百分率(tail DNA%)及彗星状拖尾(comet tail)尾长显著增加,并呈剂量-效应依赖性关系,说明低浓度甲醛具有致HepG2细胞DNA链断裂(DNA strand breakages)作用;而较高浓度(125,625μmol/L)甲醛处理后HepG2细胞尾部DNA百分率及彗星状拖尾尾长则以剂量依赖性方式显著降低,提示较高浓度甲醛具有致HepG2细胞DNA-蛋白质交联物(DNA-protein cross-links,DPXs)形成作用.
To observe the genotoxic effects of formaldehyde in human hepatoma cell line HepG2, the cultured HepG2 cells are used as the experimental material and the effects on DNA damage in HepG2 cells exposed to different concentrations of formaldehyde for 2 hours are analyzed by the single cell gel electrophoresis (SCGE) assay. It is found that a significant dose-dependent increment in both tail DNA ~ and comet tail length is detected at low concentrations of formaldehyde (5, 25 ~tmol/L) in HepG2 cells, it indicates that low concentrations of formaldehyde could cause DNA strand breakages; however, at higher concentrations of formaldehyde (125, 625 tzmol/L) a reduction in both tail DNA % and comet tail length is significantly observed in a concentration-related manner, it suggests that higher concentrations of formaldehyde could cause the induction of DNA-protein cross-links in HepG2 ceils.