Circulating endothelium-enriched microRNA-126 as a potential biomarker for coronary artery disease in type 2 diabetes mellitus patients.

Circulating microRNAs (miRNAs) have been shown as promising biomarkers for various diseases. We investigated the predictive potential of circulating endothelium-enriched miR-126 in type 2 diabetes patients (T2D) without chronic complications and T2D patients with coronary artery diseases (CAD). The expression levels of circulating miR-126, determined by quantitative real time PCR, were decrease in peripheral blood of T2D patients and T2D with CAD compared with healthy controls. MiR-126 strongly associated with T2D and CAD, negatively correlated with LDL in CAD patients and differentiated between T2D patients, T2D patients with CAD and healthy subjects. Circulating miR-126 may serve as a biomarker for predicting patients with T2D and diabetic CAD.

Decreased expression of circulating microRNA-126 in patients with type 2 diabetic nephropathy: A potential blood-based biomarker.

Circulating microRNAs (miRNAs) have been proposed as promising biomarkers for multiple diseases. miR-126 is reported to be associated with type 2 diabetes mellitus (T2D), diabetic nephropathy (DN) and end stage renal disease. The aim of this study was to investigate the expression of circulating miR-126 and to assess its potential as a blood-based biomarker for DN in T2D patients. In 52 patients with T2D without history of DN (with noromoalbuminuria), 50 patients with T2D and DN (29 with microalbuminuria and 21 with macroalbuminuria), and 50 non-diabetic healthy controls, the expression of circulating miR-126 in peripheral whole blood was evaluated by quantitative polymerase chain reaction. The expression levels of circulating miR-126 were significantly decreased in T2D patients and further decreased in DN patients compared with those in the controls. Multivariate logistic regression analysis confirmed the independent association of lower miR-126 levels with T2D [adjusted odds ratio (OR), 0.797; 95% confidence interval (CI), 0.613-0.960] and DN (adjusted OR, 0.513; 95% CI, 0.371-0.708). miR-126 levels were associated with the degree of albuminuria and showed significantly low expression in DN patients with microalbuminuria (adjusted OR, 0.781; 95% CI; 0.698-0.952) and further lower expression in DN patients with macroalbuminuria (adjusted OR, 0.433; 95% CI, 0.299-0.701), respectively compared with T2D patients with normoalbuminuria. miR-126 levels negatively correlated with albuminuria positively with glomerular filtration rate (P<0.05), and in addition, negatively correlated with fasting glucose, glycated hemoglobin, triglyceride and LDL (P<0.05). Stepwise multiple regression analysis identified albuminuria as a significant predictor of miR-126 (P<0.001). miR-126 in peripheral blood yielded area under the receiver operating characteristic curves of 0.854 (95% CI, 0.779-0.929) and 0.959 (95% CI, 0.916-1.000) in the differentiation of DN patients from T2D patients and DN patients from non-diabetic controls respectively. These data suggest that decreased expression of circulating miR-126 is associated with the development of DN in T2D patients, and may be a promising blood-based biomarker for DN risk estimation.

Peripheral blood microRNA-15a is a potential biomarker for type 2 diabetes mellitus and pre-diabetes.

MicroRNAs (miRNAs) are small non-coding RNAs that function as crucial regulators of gene expression. Recently, dysregulation of miRNA expression in the blood has been demonstrated to be associated with various diseases, including type 2 diabetes mellitus (T2D), suggesting a potential for their use as biomarkers of disease prognosis. The present study examined the expression levels of T2D­associated miR­15a in peripheral whole blood samples from patients with T2D, pre­diabetes individuals exhibiting impaired fasting glucose (IFG) and impaired glucose tolerance (IGT), as well as healthy control subjects, in order to investigate the potential of peripheral blood plasma miR­15a as a biomarker for the prediction of T2D and pre­diabetes. The present study included 24 patients with T2D, 22 IFG/IGT individuals and 24 healthy controls. The expression levels of miR­15a were analyzed by reverse transcription-quantitative polymerase chain reaction. The results indicated that the peripheral blood miR­15a expression levels were significantly decreased in patients with T2D and IFG/IGT individuals, compared with healthy control subjects (P<0.05). As determined by multivariate logistic regression analysis, lower miR­15a expression was significantly associated with T2D (odds ratio [OR]; 95% confidence interval [CI]: 0.51; 0.16­0.73, respectively; P<0.05) and pre­diabetes (OR; 95% CI: 0.56; 0.23­0.79, respectively; P<0.05). This association remained statistically significant following adjustment for age, body mass index and hypertension, as well as other biochemical indicators. Furthermore, a receiver operating characteristic analysis revealed that blood miR­15a distinguished patients with T2D and IFG/IGT individuals from healthy controls (area under the curves; 95% CI: 0.864; 0.751­0.977 and 95% CI: 0.852; 0.752­0.953, respectively). These results demonstrated that peripheral blood miR­15a expression levels were significantly lower in patients with T2D and IFG/IGT individuals, compared with healthy individuals. Thus, miR­15a in peripheral whole blood may serve as a potential biomarker for T2D and pre-diabetes.