Susceptibility of erythrocyte lipids to oxidation and erythrocyte antioxidant status in myocardial infarction

Objective: We evaluated the erythrocyte lipid susceptibility to oxidation and erythrocyte antioxidant status in patients with myocardial infarction (MI). Design and methods: Patients with MI were divided into two group according to the severity of the disease as severe (n = 30) or milder (n = 25). Malondialdehyde as a marker of lipid peroxidation was measured to show the lipid susceptibility to oxidation. Erythrocytes were stressed in vitro by hydrogen peroxide acting as the oxidative agents for 120 min. After designated time, erythrocyte MDA production was significantly higher in patients with severe MI than in controls and in patients with milder MI (p < 0.001, p < 0.001, respectively). Antioxidant status was determined by measuring the reduced glutathione levels and glutathione peroxidase activity of erythrocyte. Results: In patients with MI, antioxidant status was significantly lower than in controls, and there was no significant difference between the patient groups. Conclusion: Determination of erythrocyte lipid susceptibility to oxidation may be a useful in vitro test to evaluate the degree of oxidative stress in myocardial infarction. (C) 1998 The Canadian Society of Clinical Chemists.