Potential value of circulating microRNA-126 and microRNA-210 as biomarkers for type 2 diabetes with coronary artery disease

Background: Macrovascular complications are the main cause of morbidity and mortality among the diabetic patients. MicroRNAs (miRNAs), a family of small non-coding RNAs, play vital roles in the regulation of blood glucose level and the concurrent cardiovascular complications of type 2 diabetes. We hypothesized that plasma miR-126 and miR-210 are linked to coronary artery disease (CAD) in these diabetes patients. Methods: Fasting blood samples were collected from 20 healthy volunteers and 100 patients with diabetes (54 patients without CAD and 46 patients with CAD). Plasma miR-126 and miR-210 expressions were assessed by quantitative real time PCR. Specificity and sensitivity of miR-126 and miR-210 to discriminate CAD with diabetes was determined by receiver operating characteristic curve analysis. Correlations between miR-126 and miR-210 and studied characteristics in diabetes patients with and without CAD were compared. Results: Plasma relative expressions of miR-126 and miR-210 were 0.380.03 and 5.3 +/- 0.56 in diabetes alone vs. 0.08 +/- 0.03 and 21.44 +/- 0.97 in diabetes with CAD, respectively (both p < 0.0001). Levels of miR-126 and miR-210 significantly correlated with certain glycemic and lipid indices. The miRNAs significantly discriminated between diabetes with and without CAD at cut-off values of 0.055 (sensitivity 91.3%, specificity 100%) for miR-126 and of 17.59 (sensitivity 93.5%, specificity 100%) for miR-210. Conclusion: Plasma miR-126 and miR-210 levels may be biomarkers for diabetes with or without CAD.