姜黄素致人结肠癌HT-29细胞DNA损伤作用

目的 探讨姜黄素致人结肠癌HT-29细胞线粒体DNA(mtDNA)和核DNA(nDNA)损伤作用。方法 人结肠癌HT-29细胞暴露于不同质量浓度的姜黄素(0.0,2.5,5.0,10.020.0μg/ml)2h后,采用长链PCR方法分别扩增mtDNA和nDNA片段,琼脂糖凝胶电泳检测扩增产物量。结果 mtDNA扩增产物在5.0μg/ml姜黄素作用下明显下降,在5.0,10.020.0μg/ml作用下mtDNA损伤频率分别为(1.23±0.10),(1.97±0.24)和(5.78±0.62)/10kb,与对照组比较,差异均有统计学意义(P<0.01);nDNA扩增产物在20.0μg/ml姜黄素作用下才明显下降,在5.0,10.0,20.0μg/ml作用下nDNA损伤频率分别为(0.27±0.04),(0.61±0.11)和(1.61±0.12)/10kb,与对照组比较,除5.0μg/ml作用组外差异均有统计学意义(P<0.01)。结论 姜黄素对HT-29细胞的mtDNA和nDNA损伤均呈剂量依赖关系,并且对mtDNA的损伤作用明显大于nDNA。

Comparison of curcumin-induced damage of mitochondrial DNA and nuclear DNA by long PCR

Objective To compare the damage effects of crown in on mitochondrialDNA (mtDNA)and nuclea DNA (nDNA)in human colon cancer cell line HT-29.Methods After HT-29 cells were exposed to various concentrations of cureum in (0,2.5,5.0,10.0,20.0μg/ml) for 2h,high molecular weight DNA was isolated and long polymerase chain reaction (LPCR) assay was perfouned to deteun ine the damage of mtDNA and nDNA.Results A 2h exposure of HT-29 cells to cureum in led to a dose-dependent decrease in the amplification of both mtDNA and nDNA.Loss of amplification of the mtDNA occurred at a lower dose of curcum in (5μg/ml) compared with the nDNA(10μg/ml).For mtDNA,DNA lesion frequencies for groups with different concentrations of cureum in (5,10 and 201μ/ml) were 1.23±0.10,1.97±0.24 and 5.78±0.62 lesions/10kb(P<0.01),and that of for nDNA were 0.27±0.04,0.61±0.11 and 1.61±0.12 lesions/10kb,respectively.Conclusion In HT-29 cells,curcum in induces DNA dam age to both m1DNA and nDNA,and the damage to mtDNA is more serious as compared with nDNA.