PFOS and PFHxS Disrupt Forskolin-Induced Syncytialization but Differentially Affect hCGβ Production in BeWo Cells

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) have been used in a wide range of consumer products and industrial applications. However, because of their long persistence in the environment and the human body, there is growing concern about their effects on health. The detection of PFAS in the blood of pregnant women and the placenta has highlighted the urgent need to evaluate their effects on reproduction and development. In this study, we used perfluorooctane sulfonate (PFOS) and perfluorohexane sulfonate (PFHxS), which are PFAS already regulated by the Stockholm Convention, and investigated their effects on placental syncytialization, a key process in placental development. First, we assessed the effect of PFOS and PFHxS on BeWo cell fusion and showed that both PFAS significantly suppressed fusion at noncytotoxic concentrations. Real-time RT-PCR analysis showed that mRNA levels of syncytialization markers were reduced in both PFOS- and PFHxS-treated cells. The production of hCGβ, normally upregulated during syncytialization, was significantly reduced in PFOS-treated groups but not in PFHxS-treated groups. These results, showing that PFOS and PFHxS both disrupt BeWo cell fusion while only PFOS suppresses hCGβ production, highlight the need for further investigation into the effects of PFAS on placental and fetal development.