Effect of neonatal exposure on male rats to bisphenol A on the expression of DNA methylation machinery in the postimplantation embryo.

Bisphenol A (BPA) is used in the production of polycarbonate plastics and epoxy resins. Our previous studies have demonstrated that neonatal exposure of male rats to BPA causes decrease in sperm count and motility, increase in postimplantation loss (POL), ultimately leading to subfertility during adulthood. Epigenetic mechanisms such as DNA methylation play an important role in embryo development. DNA methyltransferases (Dnmts) are the key players involved in regulating DNA methylation marks. The objective of the present study was to determine the mechanism involved in resorption of embryo as a result of BPA exposure. The results of the present study demonstrate that neonatal exposure of male rats to BPA down regulates the gene expression of Dnmts and related transcription factors in resorbed embryos as compared with the viable embryo. Thereby, suggesting that BPA may have altered the sperm epigenome, which might have affected the embryo development and leading to an increase in the POL.