Background: Cyclophilin A is a secretedmolecule that has a physiological and pathological role in cardiovascular diseases. However, limited information is available on the relationship between cyclophilin A concentration and acute coronary syndromes (ACS). Weinvestigatedwhether cyclophilin A concentration is related to the stability of coronary atherosclerotic plaque in patients with ACS.

Methods: This study included normal controls (n=50), patients with stable angina (SA) (n=60) and patients with ACS, including unstable angina (UA) (n=60) and acute myocardial infarction (AMI) (n=90). Serum soluble cyclophilin A, matrixmetalloproteinase 9 (MMP-9),MMP-3 and C-reactive protein concentrations (CRP) were measured. All coronary stenosis were assessed by angiographic coronary stenosis morphology.

Results: Serumcyclophilin A concentration in ACS (UA and AMI ) subjectswere significantly higher than those in patients with SA and controls (pb0.05). Serumcyclophilin A correlated positivelywith serum MMP-3 andMMP-9 and CRP in ACS patients(r1=0.69, r2=0.52, r3=0.49 pb0.0001), but not in control. Furthermore, the increased cyclophilin A concentrations was associated with the number of complex coronary stenoses (r1=0.63,pb0.0001), but not smooth lesions or stenosis severity, in coronary artery disease patients. Logistic regression analysis also demonstrated that serum cyclophilin A concentration was an independent predictor factor for ACS( OR, 2.721, 95% CI 1.563–4.042, p=0.001).

Conclusion: Patients with ACS showed that increased concentrations of cyclophilin A may be a valuable marker
for predicting the severity of ACS.