彗星电泳法检测阿魏酸 咖啡酸对脱氧核糖核酸氧化损伤的影响

The effects of ferulic acid and caffeic acid on DNA damage with comet assay

目的研究在细胞水平阿魏酸、咖啡酸对脱氧核糖核酸(DNA)氧化损伤的影响。方法分别用不同浓度(50、100、500μmol/L)阿魏酸、咖啡酸对人外周血淋巴细胞预处理后,过氧化氢(H2O2)于4℃下作用10 min,并用500μmol/L咖啡酸对细胞进行处理(未经H2O2作用),采用单细胞凝胶电泳法,以彗星尾距为指标进行测量、分析。结果阿魏酸各浓度组彗星尾距较阳性对照组都有显著减小,并随剂量的增加,尾距呈减小趋势;咖啡酸在100μmol/L时尾距较阳性对照组显著减小,而在500μmol/L时尾距较低浓度组有所增加,并与100μmol/L浓度之间差异有统计学意义;用500μmol/L咖啡酸对细胞进行处理(未经H2O2作用),尾距较对照组显著增加。结论阿魏酸在细胞水平显示出较强的抗氧化保护DNA的作用,而且保护作用有随作用浓度增加而增强的趋势;咖啡酸保护DNA的作用较弱,高浓度组咖啡酸(500μmol/L)表现出明显的DNA损伤作用,证明咖啡酸具有抗氧化和氧化增强的双重作用。

Ojective To investigate the effects of ferulic acid and caffeic acid on DNA damage.Methods The single cell gel electrophoresis（comet assay） was employed to assess DNA damage of human lymphocytes pre-treated with various concentrations（50,100,500 μmol/L） of ferulic acid and caffeic acid,then challenged with H2O2 at 4 ℃ for 10 min,or treated with 500 μmol/L caffeic acid（without H2O2 challenged）.The fluorescence microscope（200×） was introduced to observe DNA damage.ANOVA analysis was performed on tail moment.Results Compared to positive control,the tail moments were all reduced after pretreatment of the cells with ferulic acid at different concentrations and then challenged with H2O2,and the decreasing trend was shown with the increased dose.Whereas caffeic acid at high dose（500 μmol/L） exhibited greater tail moment than low doses（50,100 μmol/L） groups.The tail moment showed markedly increasing compared to control group after treatment of the cells with caffeic acid（500 μmol/L） at 37 ℃ for 30 min（without H2O2 challenged）.Conclusion Ferulic acid offered significant DNA protective effects,which showed a dose-dependent trend.Caffeic acid exhibits both antioxidative and pro-oxidative effects.