Lipid and protein oxidation and antioxidant status in patients with angiographically proven coronary artery disease

Objectives We aimed to evaluate the association of lipid peroxidation, protein oxidation and antioxidant system, and to assess an association with the severity of the disease, in patients with and without coronary artery disease (CAD) documented by coronary angiography. Design and methods The population included 208 patients, undergoing clinically indicated coronary angiography. While the subjects with normal coronary angiograms (n = 54) were evaluated as controls, the patients with CAD (n = 154) were divided into three categories according to the number of diseased coronaries; one-vessel (n = 50), two-vessels (n = 51) and three-vessels (n = 53). Lipid parameters were determined by routine laboratory methods. Plasma malondialdehyde and vitamin E concentrations were determined with the high-performance liquid chromatography. Other oxidant and antioxidant parameters were studied spectrophotometrically. Results While plasma malondialdehyde levels, the susceptibilities of erythrocyte and apolipoprotein B containing lipoproteins to in vitro induced oxidative stress, serum protein carbonyls, low density lipoprotein-cholesterol, triglyceride, apolipoprotein B and lipoprotein (a) levels had significantly increased, high-density lipoprotein–cholesterol and apolipoprotein AI levels, erythrocyte glutathione peroxidase, glutathione reductase, glucose 6 phosphate dehydrogenase, serum catalase, paraoxonase and arylesterase activities, plasma vitamin E and C and carotenoid levels had significantly decreased. The odds ratios for one-, two-, and three-vessel disease increased across especially higher tertiles of concentrations for oxidation parameters and lower tertiles of concentrations for antioxidant parameters. Conclusions According to the results, we suggest that increased lipid and protein oxidation products and decreased antioxidant enzymes and vitamins contribute to increased oxidative stress which in turn is related to the severity of the disease.