The relationship between paraoxonase-1 activity and coronary artery disease in patients with metabolic syndrome

Objectives: We investigated the correlation of serum paraoxonase-1 (PON-1) activity with coronary artery disease (CAD) in patients with metabolic syndrome (MetS). Study design: The study included 21 patients (mean age 55 +/- 9 years) with MetS, stable angina pectoris, and angiographically shown CAD, 24 patients (mean age 51 +/- 10 years) with MetS and angiographically normal coroner arteries, and 28 healthy controls (mean age 49 +/- 12 years). Demographic and clinical characteristics, insulin levels, homeostasis model assessment of insulin resistance index, and PON- 1 activity were assessed in all the groups. Severity of CAD was assessed using the Gensini score. Results: Paraoxonase-1 activity was significantly lower in patients with MetS compared to the control group (p= 0.02). The two MetS groups with and without CAD exhibited similar characteristics in all the parameters including PON-1 activity (p>0.05). Univariate correlation analysis performed in MetS-CAD patients showed a significant negative correlation between the Gensini score and PON-1 activity (r=-0.48, p=0.02). The overall PON- 1 activity of all the subjects showed no correlation with the parameters examined. Conclusion: Decreased PON-1 activity in patients with MetS compared to the control group suggests increased oxidative stress in MetS. Detection of similar PON-1 activity levels in MetS groups with and without CAD suggests that disturbance of oxidative- antioxidative balance occurs before the development of CAD. The negative correlation between the Gensini score and PON-1 activity implies that decreased PON-1 activity may be one of the etiologic causes of atherosclerotic progress in MetS.