Exposure to PM2.5 during pregnancy or lactation increases methylation while reducing the expression of Pdx1 and NEUROG3 in mouse pancreatic islets

Abstract

Air pollution is comprised of several substances, including particulate matter (PM). Exposure to air pollution may trigger alterations in DNA methylation thus modifying gene expression patterns. This phenomenon is likely to mediate the relationship between exposure to air pollution and adverse health effects. The purpose of this study was analyzing the effects of exposure to PM2.5 during pregnancy or lactation and whether it would cause multigenerational epigenetic alterations in the promoter region of the genes Pdx1 and NEUROG3 within mouse pancreatic islets. Our results show that maternal exposure to PM2.5 led to an elevation in blood glucose levels within the two following generations (F1 and F2). There was also an increase in DNA methylation in the aforementioned promoter regions accompanied by reduced gene expression in generations F1 and F2 upon F0 exposure to PM2.5 during pregnancy. These data suggest that maternal exposure to PM2.5 from air pollution, particularly during pregnancy, may lead to a multigenerational and lifelong negative impact on glucose homeostasis mediated by an increase in DNA methylation within the promoter region of the genes Pdx1 and NEUROG3 in pancreatic islets.