Analysis of epigenetic changes induced by exposure to a mixture of endocrine disrupting chemicals in the mouse brain and a hippocampus mouse cell model

Abstract: Prenatal exposure to mixture N1, a chemical mixture consisting of four phthalate diesters,three pesticides and Bisphenol A, has been associated with behavioural changes as well as changes in gene expression in mice. In this study it was investigated whether the changes in gene expression could be explained by changes in DNA methylation. Mixture N1 was found to significantly change DNA methylation in three different genes (Nr3c1, Nr3c2 and Crhr1) on totally eight different Cytosine Guanine dinucleotides (CpG) positions. To further investigate whether these changes could be induced already during differentiation of cells, a hippocampal cell model HT22 was exposed to mixture N1 during differentiation. In this mode, mixture N1 induced a statistically significant change in the promoter region of Nr3c1. Unfortunately, this change could however not be validated, and the experiments would need to be repeated. In conclusion, this study showed that exposure to mixture N1 can result in changes in DNA methylation.