Downregulation of MicroRNA-130a Contributes to Endothelial Progenitor Cell Dysfunction in Diabetic Patients via Its Target Runx3

Shu Meng,Lu Fang,Jiatian Cao,Yuqi Fan,Changqian Wang,Da Fu,Yigang Li,Xiaoping Zhang,Zhongwei Lv,Gian Paolo Fadini

doi:10.1371/journal.pone.0068611

Abstract

Dysfunction of endothelial progenitor cells (EPCs) contributes to diabetic vascular disease. MicroRNAs (miRs) have emerged as key regulators of diverse cellular processes including angiogenesis. We recently reported that miR-126, miR-130a, miR-21, miR-27a, and miR-27b were downregulated in EPCs from type II diabetes mellitus (DM) patients, and downregulation of miR-126 impairs EPC function. The present study further explored whether dysregulated miR-130a were also related to EPC dysfunction. EPCs were cultured from peripheral blood mononuclear cells of diabetic patients and healthy controls. Assays on EPC function (proliferation, migration, differentiation, apoptosis, and colony and tubule formation) were performed. Bioinformatics analyses were used to identify the potential targets of miR-130a in EPCs. Gene expression of miR-103a and Runx3 was measured by real-time PCR, and protein expression of Runx3, extracellular signal-regulated kinase (ERK), vascular endothelial growth factor (VEGF) and Akt was measured by Western blotting. Runx3 promoter activity was measured by luciferase reporter assay. A miR-130a inhibitor or mimic and lentiviral vectors expressing miR-130a, or Runx3, or a short hairpin RNA targeting Runx3 were transfected into EPCs to manipulate miR-130a and Runx3 levels. MiR-130a was decreased in EPCs from DM patients. Anti-miR-130a inhibited whereas miR-130a overexpression promoted EPC function. miR-130a negatively regulated Runx3 (mRNA, protein and promoter activity) in EPCs. Knockdown of Runx3 expression enhanced EPC function. MiR-130a also upregulated protein expression of ERK/VEGF and Akt in EPCs. In conclusion, miR-130a plays an important role in maintaining normal EPC function, and decreased miR-130a in EPCs from DM contributes to impaired EPC function, likely via its target Runx3 and through ERK/VEGF and Akt pathways.

Highlights

Coronary artery disease (CAD), a leading cause of death worldwide, is largely initiated with various endothelial injuries
We reported that miR-130a was downregulated in endothelial progenitor cells (EPCs) derived from patients with diabetes [25], suggesting that the low level of miR-130a in diabetic EPCs may be involved in functional impairment of EPCs in these patients
Our findings suggest that miR-130a plays an important role in maintaining normal EPC function, and decreased miR130a in EPCs from Diabetes mellitus (DM) contributes to impaired EPC function, which is likely due to increased Runx3 and decreased vascular endothelial growth factor (VEGF)

Summary

Introduction

Coronary artery disease (CAD), a leading cause of death worldwide, is largely initiated with various endothelial injuries. EPC dysfunction may play an important role in atherosclerosis and CAD. Diabetes mellitus (DM) is one of the most important risk factors for CAD, and CAD, in turn, is a major cause of death in patients with type II DM [4]. The loss of the modulatory role of endothelium is a critical and initiating factor in the development of diabetic vascular disease. Studies have demonstrated that DM reduces the number of EPCs and adversely affects the functional capacity of existing EPCs [5,6], leading to a subsequent reduction in the ability of EPCs to repair the vascular endothelium [7,8,9]. Elucidating the basic mechanisms responsible for the diabetes-associated defects in EPC function is exceptionally important and has a high clinical impact on future interventional research

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