Homocysteine and lipid peroxidation markers in patients with coronary heart disease

Abstract

Several potential mechanisms of homocysteine (Hcy) influence on the pathogenesis of atherosclerosis including lipid peroxidation are described. The aim of this study was to determine a possible relationship between blood serum Hcy levels and lipid peroxidation in patients suffering from coronary heart disease of various stages. Serum Hcy level was determined by the fluorescence polarization immunoassay (FPIA) method with an IMx ABBOTT analyser. Malondialdehyde (MDA) concentration and catalase (CAT) activity were measured spectrophotometrically. Patients were grouped into: 1) individuals suffering from acute myocardial infarction (AMI, n = 32); 2) patients with unstable angina pectoris (USAP, n = 23); 3) individuals with stable angina pectoris (SAP, n = 25). Eighteen healthy volunteers comprised the control group. The results showed that there were no differences in Hcy levels among all study groups, although the level of the circulating marker of oxidative stress – MDA – was elevated in patients with AMI and with SAP if compared with the control group (3.22 ± 1.27, 3.74 ± 0.73, 2.73 ± 0.29 μmol/l, respectively). A weak positive correlation was found between blood Hcy and MDA levels in patients with SAP (r = 0.13). Total Hcy concentration was shown to have a weak tendency to correlate with blood serum CAT activity in patients with USAP (r = 0.27) and SAP (r = 0.15). Patients in all groups showed a higher CAT activity than the control individuals (53.03 ± 22.47, 52.32 ± 18.43, 52.77 ± 16.41, and 30.63 ± 11.98 nmol/l/min, respectively). The adaptive increase of antioxidative enzyme activity (in the case of catalase) is suggested to be related to oxidative stress as a result of homocysteine action in lipid peroxidation. Keywords: atherosclerosis, lipid peroxidation, malondialdehyde, catalase activity, homocysteine