MicroRNA-139-5p upregulation is associated with diabetic endothelial cell dysfunction by targeting c-jun.

Dysfunction of endothelial cells (ECs) and their progenitor cells is an important feature of diabetic vascular disease. MicroRNA (miR)-139-5p is involved in inhibiting the metastasis and progression of diverse malignancies. However, the role of miR-139-5p in ECs still remains unclarified. Here we demonstrated that miR-139-5p expression was elevated in endothelial colony-forming cells (ECFCs) isolated from patients with diabetes, ECs derived from the aorta of diabetic rodents, and human umbilical vein endothelial cells (HUVECs) cultured in high glucose media. MiR-139-5p mimics inhibited tube formation, migration, proliferation, and down-regulated expression of c-jun, vascular endothelial growth factor (VEGF), and platelet-derived growth factor (PDGF)-B, in ECFCs and HUVECs, respectively; moreover, miR-139-5p inhibitors reversed the tendency. Further, gain- and-loss function experiments and ChIP assay indicated that miR-139-5p regulate functions of ECFCs by targeting c-jun-VEGF/PDGF-B pathway. In vivo experiments (Matrigel plug assay and hindlimb ischemia model) showed that miR-139-5p downregulation further promoted ECFC-mediated angiogenesis and blood perfusion. In conclusion, diabetes-mediated high miR-139-5p expression inhibits the c-jun-VEGF/PDGF-B pathway, thus decreasing ECFCs migration, tube formation and proliferation, which subsequently reduces ECs survival. Therefore, miR-139-5p might be an important therapeutic target in the treatment of diabetic vasculopathy in the future.