MiR-34a-5p inhibition attenuates LPS-induced endothelial cell injury by targeting FOXM1.

OBJECTIVE

This study aims to investigate the role of miR-34a-5p in the regulation of lipopolysaccharide (LPS)-induced injury of vascular endothelial cells (ECs).

MATERIALS AND METHODS

Human umbilical vein ECs (HUVECs) were exposed to LPS to stimulate endothelial injury in vitro. miRNA microarray analysis was carried out to identify miR-34a-5p expression in HUVECs. MTT and flow cytometry analyses were used to determine cell viability and apoptosis rate, respectively. Furthermore, enzyme-linked immunosorbent assay (ELISA), qRT-PCR, and Western blot were used to examine the factors involved in inflammation and their relative gene expression. Additionally, Matrigel-based tube formation assay was carried out to assess the vasculogenic activity of HUVECs. Luciferase reporter assay was used to analyze the possible relationship between miR-34a-5p and FOXM1.

RESULTS

MiR-34a-5p expression was significantly enhanced in HUVECs after 24 h of LPS treatment. LPS treatment led to a dramatic inhibition of cell viability, enhanced apoptosis, increased production of pro-inflammatory cytokines, and inhibited the vasculogenic activity of HUVECs. MiR-34a-5p inhibitor attenuated LPS-induced damage. MiR-34a-5p directly inhibited the expression of FOXM1, and its overexpression alleviated the protective effect of FOXM1 on cell viability, apoptosis, inflammation factor production, and vasculogenic activity. The activity of the NRF2/HO-1 pathway was inhibited by miR-34a-5p, possibly via FOXM1.

CONCLUSIONS

MiR-34a-5p inhibition attenuates LPS-induced EC injury by targeting FOXM1 via activation of the NRF2/HO-1 pathway.