Inhibitory Impact of Prenatal Exposure to Nano-Polystyrene Particles on the MAP2K6/p38 MAPK Axis Inducing Embryonic Developmental Abnormalities in Mice

Nanoplastics, created by the fragmentation of larger plastic debris, are a serious pollutant posing substantial environmental and health risks. Here, we developed a polystyrene nanoparticle (PS-NP) exposure model during mice pregnancy to explore their effects on embryonic development. We found that exposure to 30 nm PS-NPs during pregnancy resulted in reduced mice placental weight and abnormal embryonic development. Subsequently, our transcriptomic dissection unveiled differential expression in 102 genes under PS-NP exposure and the p38 MAPK pathway emerged as being significantly altered in KEGG pathway mapping. Our findings also included a reduction in the thickness of the trophoblastic layer in the placenta, diminished cell invasion capabilities, and an over-abundance of immature red cells in the blood vessels of the mice. In addition, we validated our findings through the human trophoblastic cell line, HTR-8/SVneo (HTR). PS-NPs induced a drop in the vitality and migration capacities of HTR cells and suppressed the p38 MAPK signaling pathway. This research highlights the embryotoxic effects of nanoplastics on mice, while the verification results from the HTR cells suggest that there could also be certain impacts on the human trophoblast layer, indicating a need for further exploration in this area.