Diabetes mellitus represents a complex metabolic disorder expressed in glucose, lipoprotein disturbances and increased oxidative stress. The effects of the hypolipidaemic drug ciprofibrate on plasma levels of lipids, lipoproteins and the activities of antioxidant enzymes in diabetics (diabetes mellitus type 2) with atherogenic lipoprotein phenotype (ALP) were studied. No differences in glucose (8.85 ± 2.46 vs 8.11 ± 2.65) and HbA1C (7.23 ± 1.35 vs 7.10 ± 1.35) in plasma and BMI (29.4 ± 3.6 vs 29.4 ± 3.6) were found after three months of ciprofibrate therapy. Ciprofibrate treatment significantly decreased total cholesterol (–5%, p<0.05) and triacylglycerol levels (–50%, p<0.001) and increased HDL-cholesterol (+8.5%, p<0.05). Antioxidant enzyme activities, superoxide dismutase in erythrocytes (SOD) (+33%, p<0.05), glutathione peroxidase (GPx) in the blood (+20%, p<0.05) as well as the glutathione levels (GSH) (+27%, p<0.001), the main endogenous antioxidant, increased significantly after cipro- fibrate therapy. Plasma glutathione reductase activity decreased significantly (–12%, p<0.001), while glutathio- ne-S-transferase activities did not change. The results suggest, that the activities of antioxidant enzymes studied, are affected differently by ciprofibrate and their changes might form a powerful protection against oxidative injury.

        Key words: diabetes mellitus, serum lipids, superoxide dismutase, glutathione peroxidase, ciprofibrate.