Two representative DNA adducts from acrylamide exposure, N7-(2-carbamoyl-2-hydroxyethyl) guanine (N7-GA-Gua) and N3-(2-carbamoyl-2-hydroxyethyl) adenine (N3-GA-Ade), are important long-term exposure biomarkers for evaluating genotoxicity of acrylamide. Catechins as natural antioxidants present in tea possess multiple health benefits, and may also have the potential to protect against acrylamide-induced DNA damage. The current study developed an ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC−MS/MS) method for simultaneous analysis of N7-GA-Gua and N3-GA-Ade in tissues and urine. The validated UHPLC−MS/MS method showed high sensitivity, with limit of detection and limit of quantification ranging 0.2–0.8 and 0.5–1.5 ng/mL, respectively, and achieved qualified precision (RSD<14.0%) and spiking recovery (87.2%–110.0%) with elution within 6 min, which was suitable for the analysis of the two DNA adducts in different matrices. The levels of N7-GA-Gua and N3-GA-Ade ranged 0.9–11.9 and 0.6–3.5 μg/g creatinine in human urine samples, respectively. To investigate the interventional effects of catechins on the two DNA adducts from acrylamide exposure, rats were supplemented with three types of catechins (tea polyphenols, epigallocatechin gallate, and epicatechin) 30 min before administration with acrylamide. Our results showed that catechins effectively inhibited the formation of DNA adducts from acrylamide exposure in both urine and tissues of rats. Among three catechins, epicatechin performed the best inhibitory effect. The current study provided evidence for the chemo-preventive effect of catechins, indicating that dietary supplement of catechins may contribute to health protection against exposure to acrylamide.

丙烯酰胺暴露的两个代表性 DNA 加合物 N7-(2-氨基甲酰基-2-羟乙基) 鸟嘌呤 (N7-GA-Gua) 和 N3-(2-氨基甲酰基-2-羟乙基) 腺嘌呤 (N3-GA-Ade) 很重要用于评估丙烯酰胺遗传毒性的长期暴露生物标志物。作为茶中存在的天然抗氧化剂儿茶素具有多种健康益处，并且还可能具有防止丙烯酰胺引起的 DNA 损伤的潜力。目前的研究开发了一种超高效液相色谱串联质谱 (UHPLC-MS/MS) 方法，用于同时分析组织和尿液中的 N7-GA-Gua 和 N3-GA-Ade。经验证的 UHPLC-MS/MS 方法显示出高灵敏度，检测限和定量限分别为 0.2-0.8 和 0.5-1.5 ng/mL，并达到合格的精密度（RSD<14.0%）和加标回收率（87.2%） –110。0%)，6 分钟内洗脱，适用于不同基质中两种 DNA 加合物的分析。人体尿液样本中 N7-GA-Gua 和 N3-GA-Ade 的水平分别为 0.9-11.9 和 0.6-3.5 μg/g 肌酐。为了研究儿茶素对丙烯酰胺暴露的两种 DNA 加合物的干预作用，在给予丙烯酰胺前 30 分钟向大鼠补充三种儿茶素（茶多酚、表没食子儿茶素没食子酸酯和表儿茶素）。我们的结果表明，儿茶素可有效抑制大鼠尿液和组织中因丙烯酰胺暴露而形成的 DNA 加合物。在三种儿茶素中，表儿茶素的抑制效果最好。目前的研究为儿茶素的化学预防作用提供了证据，