Abstract: Objective To investigate high-concentration uric acid-induced endothelial dysfunction mediated by miR-155.
Methods Human umbilical vein endothelial cells (HUVECs) were incubated with 600 μmol/L uric acid for 24 and 48 h, and
eNOS expression and NO content in the cell culture were measured. The target genes of miR-155 were predicted using on-line
analysis software and validated by dual-luciferase system. Real-time PCR was used to detect the expression of miR-155 in
endothelial cells incubated with high-concentration uric acid. The effect of miR-155 on endothelial dysfunction was assessed
by transfection of its inhibitor into HUVECs. Results The expression of eNOS and NO secretion decreased obviously in
HUVECs incubated with 600 μmol/L uric acid. MicroRNA on-line analysis software and dual luciferase reporter experiments
suggested that the level of eNOS translation was directly regulated by miR-155. The expression of miR-155 in endothelial cells
was upregulated after stimulation with high-concentration uric acid, and was inhibited by transfection of miR-155 inhibitor.
Expression of eNOS and secretion of NO were elevated in endothelial cells transfected with miR-155 inhibitor after incubation
with high-concentration uric acid. Conclusion High-concentration uric acid can down-regulate eNOS expression via miR-155
to induce endothelial dysfunction.