Sexually Dimorphic Regulation of MiR-29a/c-3p in Human Endothelial Cells: Cell Functions and Transcriptome

Preeclampsia (PE) is a major cause of maternal and fetal morbidity and mortality during pregnancy. PE is characterized by widespread endothelial dysfunction in mothers and fetuses. To date, the etiology of PE remains elusive, but the dysregulation of microRNAs (miRNAs) in endothelial cells may contribute to the pathogenesis of PE. We have reported that PE downregulates expression of two miRNAs, miR-29a-3p and miR-29c-3p (miR-29a/c-3p) and knockdown of miR-29a/c-3p impairs functions of human umbilical vein endothelial cells (HUVECs). Herein, we tested the hypothesis that knockdown of miR-29a/c-3p sex-specifically impairs cellular responses to vascular endothelial growth factor-A (VEGFA) and fibroblast growth factor 2 (FGF2) accompanying with disrupted transcriptome in HUVECs. MiR-29a/c-3p were downregulated using miR-29c-3p inhibitors in HUVECs, followed by assessing chemotactic and proliferative responses to VEGFA and FGF2. RNA-seq analysis was conducted to profile transcriptomic changes. Compared with negative control, miR-29c-3p inhibitors suppressed over 90% of miR-29a/c-3p in HUVECs at 48 h. MiR-29c-3p inhibitors decreased VEGFA-stimulated chemotaxis by 25% in male, but not female HUVECs. MiR-29c-3p inhibitors did not alter FGF2-stimulated chemotaxis or VEGFA- and FGF2-stimulated proliferation in HUVECs. RNA-seq revealed that miR-29a/c-3p inhibitors differentially altered the transcriptome between female and male HUVECs. Functional enrichment analyses showed that miR-29a/c-3p-regulated genes were differently associated with hypertension, heart, angiogenesis, and immunology in female and male HUVECs. These data demonstrate that knockdown of miR-29a/c-3p differentially affects cellular responses to angiogenic factors in female and male HUVECs, in association with disrupted transcriptome. These miR-29a/c-3p-regulated genes might serve as sex-specific therapeutic targets for PE-associated vascular dysfunction.