Pentraxin 3 (PTX3) promoter methylation associated with PTX3 plasma levels and neutrophil to lymphocyte ratio in coronary artery disease

Background Pentraxin 3 (PTX3) is expressed in the heart under inflammatory conditions and plays an important role in atherogenesis. Patients with increased PTX3 levels may suffer from higher rates of cardiac events. Regulation of specific genes by promoter methylation is important in atherogenesis. The factors influencing PTX3 levels and the association between epigenetics and PTX3 levels have not been investigated. Methods Blood samples were collected from 64 patients admitted to the Department of Cardiology, 35 who had coronary artery disease (CAD), and 29 who were CAD-free. Plasma levels of PTX3 were measured by ELISA. PTX3 promoter methylation was evaluated via methyl-specific PCR. The severity of coronary artery lesion was evaluated by angiography. Results The level of PTX3 promoter methylation in the CAD group was 62.69% ± 20.57%, significantly lower than that of the CAD-free group, which was 72.45% ± 11.84% (P = 0.03). Lower PTX3 promoter methylation levels in the CAD group were associated with higher plasma PTX3 concentrations (r = -0.29, P = 0.02). Furthermore, lower PTX3 promoter methylation levels were associated with higher neutrophil to lymphocyte ratio (NLR) in men (r = -0.58, P = 0.002). Conclusions The present study provides new evidence that methylation of the PTX3 promoter is associated with PTX3 plasma levels and NLR in coronary artery disease. This study also shows that modification of epigenetics by chronic inflammation might be a significant molecular mechanism in the atherosclerotic processes that influence plasma PTX3 concentrations.