Beetch Megan, Lubecka Katarzyna, Kristofzski Heather, Suderman Matthew, Stefanska Barbara
Food, Nutrition and Health Program, Faculty of Land and Food Systems, the University of British Columbia, Vancouver, BC, V6T 1Z4, Canada.
Department of Biomedical Chemistry, Medical University of Lodz, Lodz, 92-215, Poland.
Mol Nutr Food Res. 2018 Jul;62(14):e1800193. doi: 10.1002/mnfr.201800193. Epub 2018 Jun 26.
Searching for correlations between dietary polyphenols and risk of chronic diseases has been a challenge due to the lack of quantitative evaluation methods of long-term exposure. We previously observed substantial DNA methylation changes in human cancer cells upon treatment with polyphenols of the stilbenoid class. When induced in normal cells, such molecular changes may persist and reflect chronic exposure.
Illumina 450K microarray is used to delineate a genome wide DNA methylation landscape in MCF10A human immortalized mammary epithelial cells exposed to resveratrol (RSV) at noncytotoxic 15 μM dose for 9 days. Subtle alterations are observed suggesting remodeling of DNA methylation patterns rather than switch on/off changes. Using pyrosequencing, DNA methylation is quantitatively measured at eight CpG sites located within KCNJ4, RNF169, BCHE, DAOA, HOXA9, RUNX3, KRTAP2-1, and TAGAP, upon exposure to RSV or pterostilbene and shows similar differences induced by both stilbenoids. Two of the probes, Runx3 and Kcnj4, are successfully verified in whole blood DNA from healthy rats on diets supplemented with stilbenoids.
The study provides strong support for testing the utility of polyphenol-mediated changes in DNA methylation as quantitative measures of long-term dietary exposures in nutritional epidemiology and clinical trials.
由于缺乏长期暴露的定量评估方法，寻找膳食多酚与慢性病风险之间的相关性一直是一项挑战。我们之前观察到，用芪类多酚处理人类癌细胞后，DNA甲基化发生了显著变化。当在正常细胞中诱导时，这种分子变化可能会持续并反映长期暴露情况。
使用Illumina 450K微阵列来描绘MCF10A人永生化乳腺上皮细胞在非细胞毒性的15 μM白藜芦醇（RSV）剂量下暴露9天后的全基因组DNA甲基化图谱。观察到细微变化，表明DNA甲基化模式发生重塑，而非开启/关闭变化。使用焦磷酸测序法，对暴露于RSV或紫檀芪后位于KCNJ4、RNF169、BCHE、DAOA、HOXA9、RUNX3、KRTAP2 - 1和TAGAP内的八个CpG位点的DNA甲基化进行定量测量，结果显示两种芪类化合物诱导的差异相似。其中两个探针Runx3和Kcnj4，在补充芪类化合物饮食的健康大鼠的全血DNA中得到成功验证。
该研究为测试多酚介导的DNA甲基化变化作为营养流行病学和临床试验中长期膳食暴露定量指标的效用提供了有力支持。
