Decabromodiphenyl ethane induces intrauterine growth restriction by suppressing placental angiogenesis via TWIST2/NAT10-mediated ac4C-dependent TGF-β1 mRNA stabilization

Decabromodiphenyl ethane (DBDPE) is a brominated flame retardant widely used for its high flame retardancy and low bioavailability. However, DBDPE exhibits bioaccumulative potential. The placental vasculature, critical for the exchange between maternal and fetal circulation, is susceptible to environmental factors. We aimed to understand the potential toxicity of DBDPE to the placental vasculature. Gestational CD-1 mice and human umbilical vein endothelial cells (HUVECs) were exposed to 0, 0.5, 5, 50 mg/kg·bw·day or 0, 6.25, 12.5, 25, 50 μmol/L DBDPE, respectively. DBDPE exposure impaired placental angiogenesis and inhibited the proliferation and invasion of HUVECs by activating the endothelial-to-mesenchymal transition (EndMT) through the TGF-β1/Smad pathway, in vivo and in vitro . DBDPE upregulated the transcription factor TWIST2 and mRNA acetyltransferase NAT10. Knockdown or overexpression of TWIST2 reversed the vascular dysfunction and EndMT mechanism. DBDPE facilitated the recruitment of NAT10 by TWIST2, promoting N4-acetylcytidine (ac4C) RNA modifications and stabilizing the TGF-β1 mRNA. NAT10 inhibition rescued the effects caused by DBDPE. These findings uncover molecular mechanisms linking DBDPE exposure to adverse pregnancy outcomes, highlighting potential risks to pregnant women.