Silica nanoparticles reduce fetal weight in mice and induce an inflammatory response in human extravillous trophoblast cells

Advances in nanotechnology make the exposure to nanoparticles inevitable, potentially resulting in unexpected biological effects, particularly in pregnant women and fetuses. In this study, we used silica nanoparticles with a size of 10 nm (nSP10) and evaluated their toxicity during pregnancy in BALB/c mice. To evaluate the effect of nSP10 on the remodeling of uterine spiral arteries by extravillous trophoblast (EVT) cells, we used the human placental cell line HTR-8/SVneo, a model for EVT cells. On gestational day (GD) 10, mice were intravenously injected with a single dose of nSP10. On GD17, placental weight was not changed significantly, but fetal weight was significantly decreased by the treatment. In wound healing assay, nSP10 treatment significantly decreased the relative migration area of HTR-8/SVneo cells in a concentration-dependent manner, suggesting that nSP10 inhibits cell migration. In the cytokine array assay, nSP10-treated cells tended to produce more IL-6 and IL-8 than non-treated cells. In ELISA, nSP10 significantly increased IL-6 and IL-8 production, and JSH-23 (an inhibitor of NF-κB nuclear translocation) significantly suppressed this effect, suggesting that nSP10 increases IL-6 and IL-8 production by inducing nuclear translocation of NF-κB. Our data suggest that nSP10 reduces mouse fetal weight and may inhibit migration and induce inflammatory response of human extravillous trophoblast cells.