阿斯巴甜和糖精的基因毒性体外测试研究

In vitro testing studies on the genotoxicity of aspartame and saccharin

中文关键词:  阿斯巴甜  糖精  液相色谱串联质谱技术  高内涵筛选  基因毒性

英文关键词:aspartame  saccharin  liquid chromatography-tandem mass spectrometry  high content screening  genotoxicity

中文摘要:

      目的 探究两种常用甜味剂阿斯巴甜和糖精的基因毒性。方法 采用液相色谱-串联质谱(liquid chromatography-tandem mass spectrometry, LC-MS/MS)技术和高内涵筛选(high content screening, HCS)技术检测阿斯巴甜和糖精暴露后细胞中与DNA损伤修复途径相关的重要生物标志物, 即γ-H2AX、p-H3、Rad51和p53的表达水平, 并考察其量效和时效关系。结果 LC-MS/MS检测结果表明阿斯巴甜和糖精在考察浓度下均不会引起细胞γ-H2AX和p-H3表达增加, 即未呈现染色体断裂和纺锤体毒性; HCS检测结果显示糖精对4种生物标志物均无影响, 阿斯巴甜对p53、γ-H2AX和p-H3这3种DNA损伤生物标志物无明显影响, 但引起DNA同源重组修复(homologous recombination repair, HRR)蛋白Rad51呈现无剂量依赖性的显著增加。结论 本研究表明阿斯巴甜和糖精经两种基因毒性体外测试方法检测, 均未呈现显著DNA损伤基因毒性。

英文摘要:

      Objective To investigate the genotoxicity of two kinds of commonly used sweeteners, aspartame and saccharin. Methods Liquid chromatography-tandem mass spectrometry (LC-MS/MS) techniques and high content screening (HCS) techniques were used to detect the expression levels of the important biomarkers related to the DNA damage repair pathway in cells after aspartame and saccharin exposure. The expression levels of important biomarkers, i.e., γ-H2AX, p-H3, Rad51, and p53, were examined for their quantitative and temporal relationships. Results The LC-MS/MS results indicated that neither aspartame nor saccharin led to an increase in the expression of cellular γ-H2AX and p-H3 at the tested concentrations, suggesting the absence of chromosome breakage and spindle toxicity. The HCS assay revealed that saccharin did not affect any of 4 kinds of biomarkers. As for aspartame, it did not significantly impact the expression of the three DNA damage response biomarkers of p53, γ-H2AX and p-H3. However, aspartame did cause a significant increase in the expression of the DNA homologous recombination repair (HRR) protein Rad51, while this effect was not dose-dependent. Conclusion This study shows that aspartame and saccharin do not exhibit significant DNA damage genotoxicity when tested by two kinds of in vitro genotoxicity test methods.