Plasma circulating microRNAs in patients with stable coronary artery disease - impact of different cardiovascular risk profiles and glomerular filtration rates

Plasma circulating microRNA (miRNA)-126, -145, and -155 are associated with vascular remodeling, atherosclerotic lesion formation, and plaque vulnerability. In this study, we evaluated the levels of plasma circulating miRNAs in patients with stable coronary artery disease (CAD), different cardiovascular risk profiles, and different glomerular filtration rates (GFR).Forty patients with stable CAD admitted for elective percutaneous coronary intervention (PCI) were enrolled in a prospective study. Before PCI, fasting blood samples were obtained to evaluate clinical parameters and miRNA-126 and miRNA-155 expression. The GFR was calculated by the MDRD and CKD-EPI formulas, and the severity of CAD was calculated according to the SYNTAX score. All these parameters were correlated with miRNAs. The association between miRNA levels and clinical characteristics was evaluated. The expression of miRNA-126 positively correlated with a higher SYNTAX score (r = 0.337; p=0.034); however, no significant correlations between miR-126, GFR, and clinical characteristics were observed. Higher plasma levels of miRNA-155 correlated with increased levels of triglycerides (r = 0.317; P = 0.049), C-peptide (r = 0.452; P = 0.011), and the HOMA index (r = 0.447; P = 0.012) and a higher body mass index (BMI) (r = 0.385; P = 0.015). GFR and miRNA-155 (MDRD - Rho=0.353; P = 0.027. CKD-EPI - Rho=0.357; P = 0.026) were found to have a moderate correlation, although miRNA-155 had no correlation with the SYNTAX score.Plasma circulating miRNA-126 levels were increased in patients with severe atherosclerosis as determined by the SYNTAX score. Elevated miRNA-155 expression was observed in patients with Stage 1 GFR but was lower in patients with Stages 2 and 3 GFR. Plasma circulating miRNA-155 had positive correlations with higher levels of BMI, HOMA index, C-peptide, and triglycerides.Although further investigations are needed to confirm the role of miRNA-155 and miRNA-126, they may serve as potential biomarkers detecting severity of CAD, lowering of kidney function and metabolic syndrome.