Regulatory role and molecular mechanism of METTL14 in vascular endothelial cell injury in preeclampsia

Preeclampsia (PE) is a pregnancy-related disease characterized by vascular endothelial cell injury. This study aimed to investigate the role of methyltransferase-like protein 14 (METTL14) in vascular endothelial cell injury in PE. The PE cell model was established by treating human umbilical vein endothelial cells (HUVECs) with tumor necrosis factor-alpha (TNF-α) in vitro. METTL14 and forkhead box protein 1 (FOXP1) were silenced, and miR-34a-5p was overexpressed in HUVECs to evaluate their effects. HUVEC viability, apoptosis, and the levels of intercellular adhesion molecule 1, vascular cell adhesion molecule 1, and endothelin-1 were measured. The N6-methyladenosine (m6A) modification of pri-miR-34a-5p was quantified. The interactions between miR-34a-5p, DiGeorge syndrome critical region 8, and m6A enrichment in miR-34a-5p were analyzed. The relationship between miR-34a-5p and FOXP1 was also verified. The results showed that the expressions of METTL14, FOXP1, and miR-34a-5p were determined. METTL14 expression was elevated in the TNF-α-induced HUVEC injury model. Silencing METTL14 improved HUVEC viability, inhibited apoptosis, and reduced endothelial inflammation. METTL14 promoted miR-34a-5p expression through m6A modification. Overexpression of miR-34a-5p or silencing of FOXP1 reversed the protective effects of METTL14 silencing on cell injury in the PE model. In conclusion, METTL14 mediated m6A modification to promote miR-34a-5p expression, leading to the inhibition of FOXP1 expression, which aggravated endothelial cell damage in the PE cell model.