The Epigenetic Effect Of Environmental Estrogens Bisphenol A On Reproductive System In Male Mice

Bisphenol A is a kind of phenolic environmental estrogens, and it is a precursor tosynthesise of epoxy resin and polycarbonates in industry. Previous research hasshown that bisphenol A can play a weak estrogen like activity. Mother exposure tobisphenol A during pregnancy can lead to bisphenol A pass placental barrier and transferinto the fetus, so bisphenol A can accumulate in the fetal body and lead to fetal injury.The recent study indicates that bisphenol A can change the methylation status of somegenes through an unknown way and affect gene expression, not like it’s estrogen likeactivity.In order to clarify the epigenetic effect of environmental estrogens bisphenol A onreproductive system in male mice, pregnant female mices received intraperitonealinjection of bisphenol A for simulated an environment that mother exposure tobisphenol A during gestation. After injection, research will use gene chip technology toscreen the differentially expressed and methylation status genes in fetal testis betweenthe mice which intraperitoneal injection of BPA or oil, and then, the study will test themicroarray date by real-time quantitative RT-PCR and bisulfite DNA sequencing. Thisstudy not only lay a foundation for explaining the molecular mechanism caused by theenvironmental estrogens BPA on reproductive system disease, but also provided thetheoretical basis for the development of the dugs.Morphological observation and statistical analysisand showed that pregnant motherexposure to bisphenol A can lead the embryo stop the growth and increase the risk ofdeformity, and bisphenol A can increase the weight of placenta. The large-scale mRNAmicroarray data suggested that the genes which expression levels changed are related tometabolism and cancer. The real-time quantitative RT-PCR and DNA methylationmicroarray data revealed that bisphenol A not only play an estrogen activity by changethe expression levels of estrogen receptor genes Esr1、Esr2and androgen receptor geneAR, but also influence the DNA methylation degree of large CpG-rich regions byinhibiting the expression of DNA methyltransferase genes Dnmt3a、Dnmt3b andDnmt3L.Together, these results suggest that bisphenol A not only change gene expressionby its estrogen activity, but also influence the DNA methylation levels through DNA methyltransferase.