Cyclophilin A: a novel biomarker for cardiovascular disease in patients with type 2 diabetes

Background and aims Type 2 diabetes mellitus (DM) is a strong independent risk factor for coronary heart disease. Cyclophilin A (CyPA) is a protein secreted from vascular smooth muscle cells in response to reactive oxygen species. It is suggested that CyPA plays an important role in later stages of atherosclerosis and plaque rupture. It was demonstrated that plasma levels of CyPA are significantly higher in patients with coronary artery disease (CAD) in proportion to severity of disorder. Moreover, several studies have demonstrated a role of CyPA as a biomarker of CADs. Indeed studies revealed significantly higher plasma levels of CyPA in patients with CAD with type 2 DM. Objective To assess the severity of CAD among diabetic and prediabetic patients and predict future cardiovascular events. Patients and methods The study was conducted on 65 patients with CAD diagnosed by coronary angiography, stratified according to GRACE score into low/intermediate/high death risk categories and subdivided into diabetic, prediabetic, and nondiabetic, and 20 age-matched and sex-matched patients, who had normal angiography as a control group. Blood samples were collected for determination of glycated hemoglobin (HbA1c), serum creatinine, cardiac troponin, and CyPA level using double-antibody sandwich enzyme-linked immunosorbent assay technique. Results There were significantly higher levels of CyPA among patient group than control group (P<0.001). Moreover, significantly higher CyPA levels were detected in diabetic group when compared with normal and prediabetic groups (P<0.029). CyPA was positively correlated with HbA1c in all patients and with diabetic patients. HbA1c was negatively correlated with serum creatinine and positively with estimated glomerular filtration rate in prediabetic group and with systolic blood pressure in diabetic group. The number of occluded vessels was positively correlated with both CyPA and HbA1c. The diagnostic sensitivity and specificity of CyPA were 76.92 and 95%, respectively, at a cutoff value of more than 13 ng/ml. Conclusion CyPA can be used as an early predictor of CAD in patients with type 2 DM and also in prediabetic patients.