A systematic review of microRNA expression studies with exposure to bisphenol A.

Bisphenol A (BPA), as a common industrial component, is generally consumed in the synthesis of polymeric materials. To gain a deeper understanding of the detrimental effects of BPA, BPA-induced microRNA (miRNA) alterations were investigated. A systematic search was performed in the PubMed, SCOPUS and Web of Science databases to evoke relevant published data up to August 10, 2019. We identified altered miRNAs that have been repeated in at least three studies. Moreover, miRNA homology analysis between human and nonhuman species was performed to determine the toxicity signatures of BPA in human exposure. In addition, to reflect the effects of environmental exposure levels of BPA, the study designs were categorized into two groups, including low and high doses according to the previous definitions. In total, 28 studies encountered our criteria and 17 miRNAs were identified that were differentially expressed in at least three independent studies. Upregulating miR-146a and downregulating miR-192, miR-134, miR-27b and miR-324 were found in three studies. MiR-122 and miR-29a were upregulated in four studies after BPA exposure, and miR-21 was upregulated in six studies. The results indicate that BPA at low-level exposures can also alter miRNA expression in response to toxicity. Finally, the miRNA-related pathways showed that BPA seriously can affect human health through various cell signaling pathways, which were predictable and consistent with existing studies. Overall, our findings suggest that further studies should be conducted to examine the role of miRNA level changes in human BPA exposure.