The interleukin-17 (IL-17) has a crucial role during inflammation and has been associated with cardiovascular diseases, but its role in epigenetics is still poorly understood. Therefore, the aim of this study was to evaluate the DNA methylation status of the IL-17A gene promoter to establish whether it may represent a risk factor for subclinical atherosclerosis (SA) or clinical coronary artery disease (CAD). We included 38 patients with premature CAD (pCAD), 48 individuals with SA, and 43 healthy controls. Methylation in the CpG region of the IL-17A gene promoter was assessed via methylation-specific polymerase chain reaction (MSP). Individuals with SA showed increased methylation levels compared to healthy controls and pCAD patients, with p < 0.001 for both. Logistic regression analysis showed that high methylation levels represent a significant risk for SA (OR = 5.68, 95% CI = 2.38-14.03, p < 0.001). Moreover, low methylation levels of the IL-17A gene promoter DNA represent a risk for symptomatic pCAD when compared with SA patients (OR = 0.16, 95% CI = 0.06-0.41, p < 0.001). Our data suggest that the increased DNA methylation of the IL-17A gene promoter is a risk factor for SA but may be a protection factor for progression from SA to symptomatic CAD.
Keywords: DNA methylation; coronary artery disease; epigenetics; interleukin-17A gene; subclinical atherosclerosis.