Genome-wide microRNA expression profiling in placentas from pregnant women exposed to BPA

Background: Bisphenol A (BPA) is an environmental compounds is known to possess endocrine disruption potentials. Bisphenol A has epigenetic effects as deregulated expression of microRNAs; such epigenetic marks can induce up/ down alterations in gene expression that may persist throughout a lifetime. Bisphenol A (BPA) exposure has been documented in pregnant women, but consequences for development of offspring after BPA exposure during pregnancy are not yet widely studied. Therefore, the aim of this study was to gain a comprehensive understanding of microRNAs changes in the placenta transcriptome from pregnant women subjected to therapeutic abortion for fetal malformation and correlate the impact of gestational exposure to BPA on these developmental changes. Methods: We performed a comparative analysis of genome wide miRNA expression in placentas from pregnant women exposed to BPA using microarray technology to identify miRNAs which were aberrantly expressed in placentas from malformed fetuses. The expression changes of differential expressed miRNAs in the samples used for microarray were confirmed by qPCR. Beside, we applied various bioinformatics tools to predict the target genes of the identified miR-146a and explore their biological function and downstream pathways. Results: We found that miR-146a was significant overexpressed and correlated significantly with BPA accumulation in the placenta from pregnant women living in a polluted area and undergoing therapeutic abortion due to fetal malformations. Beside, we applied various bioinformatics tools to predict the target genes of miR-146a and explore their biological function and downstream pathways. Conclusions: For the first time, we found, in humans, that miR-146a was significant over-expressed and correlated significantly with BPA accumulation in the placenta. Our results lead to the suggestion that miRNAs could be potential biomarkers to clarify the mechanisms of environmental diseases.