Objective:

The aim of this study was to investigate the possible relationship between serum oxidized low-density lipoprotein (Ox-LDL) concentration, recently shown to be a cardiovascular risk factor, paraoxonase 1 (PON1) activity and Thiobarbituric Acid Reactive Substance (TBARS) levels, and the severity of Coronary Artery Disease (CAD) as determined by the obstructive vessel number inpatients.

Methods:

We determined plasma PON1 activity, serum Ox-LDL concentration, Apolipoprotein A1 (ApoA1) levels, TBARS levels and lipid profiles, including total cholesterol (TC), triglycerides (TG), Low-Density Lipoprotein cholesterol (LDL-C), High-Density Lipoprotein cholesterol (HDL-C), and Very Low-Density Lipoprotein cholesterol (VLDL-C), in patients with CAD (n=42) and in a healthy control group (n=17). The CAD group was divided into three subgroups with single- (n=13), double- (n=15) and triple-vessel (n=14) disease according to their angiography results. PON1 activity and TBARS levels were measured spectrophotometrically; Ox-LDL levels were determined by ELISA; ApoA1levels were determined immunoturbidometrically; and TC, TG, and HDL-C levels were determined enzymatically.

Results:

In the study we observed that PON1 activity decreases when the number of affected vessels increases (r=-0,537, p<0.01). Ox-LDL levels in single-, double- and triple-vessel disease groups and in the total CAD group were significantly higher than in the healthy control group (p <0.01). TBARS levels in single-, double- and triple-vessel disease groups were significantly higher than the healthy control group (p<0.01). Moreover, ApoA1 levels in the single-, double- and triple-vessel disease groups were significantly lower than in the healthy control group (p<0.01).

Conclusion:

Our results show that low PON1 activity, high Ox-LDL levels, high TBARS levels and low ApoA1 levels may play an important role in the pathogenesis of CAD.

Keywords: PON1, protein, human, oxidized low-density lipoprotein, Thiobarbituric Acid Reactive Substances