Preferential Epigenetic Programming of Estrogen Response after in utero xenoestrogen (bisphenol-A) exposure [Illumina]

Bisphenol-A (BPA) is an environmentally ubiquitous estrogen-like endocrine-disrupting compound. Exposure toBPAin utero hasbeen linked to female reproductive disorders, including endometrial hyperplasia and breast cancer. Estrogens are an etiological factor in many of these conditions. We sought to determine whether in utero exposure to BPA altered the global CpG methylation pattern of the uterine genome, subsequent gene expression, and estrogen response. Pregnant mice were exposed to an environmentally relevant dose of BPA or DMSO control. Uterine DNA and RNA were examined by using methylated DNA immunoprecipitation methylation microarray, expression microarray, and quantitative PCR. In utero BPA exposure altered the global CpG methylation profile of the uterine genome and subsequent gene expression. The effect on gene expression was not apparent until sexual maturation, which suggested that estrogen response was the primary alteration. Indeed, prenatal BPA exposure preferentially altered adult estrogen-responsive gene expression. Changes in estrogen response were accompanied by altered methylation that preferentially affected estrogen receptor-a (ERa)–binding genes. The majority of genes that demonstrated both altered expression and ERa binding had decreased methylation. BPA selectively altered the normal developmental programming of estrogen-responsive genes via modification of the genes that bind ERa. Gene– environment interactions driven by early life xenoestrogen exposure likely contributes to increased risk of estrogen related disease in adults.—Jorgensen, E. M.,Alderman,M.H., III,Taylor, H. S. Preferential epigenetic programmingof estrogen response after in utero xenoestrogen (bisphenol-A) exposure. Dams were exposed to 5mg/kg/day of BPA or DMSO (CTL) for day 9-21 of gestation. Offspring were oopherectomized at 6 weeks. At 8 weeks mice were given 300ng E2 or DMSO and uteri were harvested 6h later. Total RNA was analyzed. Samples were pooled by litter.