氧化剂致CHL细胞DNA损伤及酪醇的保护作用

目的 检测阿霉素、重铬酸钾和过氧化氢所致中国仓鼠肺成纤维细胞(CHL)DNA的损伤效应及酪醇对真核细胞DNA氧化损伤的保护作用.方法 CHL细胞用不同浓度化学物作用一定时间后(阿霉素:1.25h;重铬酸钾:1.75h;过氧化氢:2.5min),收获细胞用单细胞凝胶电泳技术检测DNA链断裂情况;CHL细胞先用不同浓度酪醇作用1.58h,再加入0.4mmol/L过氧化氢共同培养25min,然后用单细胞凝胶电泳技术测定DNA链断裂情况,分析酪醇的抗氧化损伤作用.结果 0.1μmol/L阿霉素、0.1mmol/L重铬酸钾及0.1mmol/L过氧化氢作用一定时间后,均可引起DNA链断裂,随着各组处理物浓度的增加,DNA迁移长度和拖尾细胞百分率也相应增加,两者剂量反应关系明显.10μg/ml、20μg/ml酪醇的预处理可使过氧化氢染毒细胞的拖尾百分率和DNA迁移长度显着降低.结论 阿霉素、重铬酸钾和过氧化氢均是强烈的DNA链断裂剂;酪醇对真核细胞DNA氧化损伤具有抑制作用.

DNA Oxidative Damage Induced by Oxidants and P-tyrosol Protection Against Hydrogen Peroxide in CHL Cells

Objective To detect the DNA strand breaks induced by adriamycin,potassium chromate or hydrogen peroxide and to study the effect of p-tyrosol on DNA oxidative damage in CHL cells.Methods Single cell gel electrophoresis assay(SCGE)was used to detect DNA strand breaks when CHL cells were induced by different concentration of compounds for certain time(adriamycin:1.25h,potassium chromate:1.75h,hydrogen peroxide:25min);SCGE was used to detect DNA strand breaks and to analyze p-tyrosol protection against oxidative damage in CHL cells which were exposed to different concentration of p-tyrosol for 1.58h firstly,and then cultured with 014mmol/L hydrogen peroxide for 25min.Results Adriamycin,potassium chromate or hydrogen peroxide tested at all concentrations,caused a significant increase in DNA migration measured as tail length and percentage of cells with migrated DNA in exposed CHL cells,and the dose-response relationships are apparent between the tail length and the concentration of compound.The pretreatment of p-tyrosol(10μg/ml or 20μg/ml)markedly decreased the tail length of CHL cells treated by hydrogen peroxide.Conclusion Adriamycin,potassium chromate and hydrogen peroxide are violent DNA breaking agent.P-tyrosol has the ability to inhibit oxidative DNA damage in eukaryote.