Importance of lipid peroxidation, protective enzymes and trace elements in chronic leg ischaemia

The aim of this study was to assess the lipid peroxidation in chronic leg ischaemia by determining thiobarbituric acid reactants. Furthermore, Cu, Zn-superoxide dismutase and glutathione peroxidase activities as well as the trace element profile (Zn, Cu, Se, Mg) were determined. Fasting blood samples from the common femoral artery and vein were taken from both legs of 15 patients (57 +/- 7 years) with peripheral arteriosclerosis and 9 individuals (54 +/- 9 years) of the control group without chronic leg ischaemia. Patients with peripheral arteriosclerosis showed significantly decreased venous thiobarbituric acid reactant levels (2.01 +/- 0.37 vs. 2.39 +/- 0.59 mumol/l in controls, p < 0.05). Both arterial and venous samples from patients showed lower Cu, Zn-superoxide dismutase activities and higher glutathione peroxidase activities than controls. Venous activities of glutathione peroxidase were significantly higher than arterial activities in both groups (patients 0.52 +/- 0.18 vs 0.43 +/- 0.15 mukat/g Hb, p < 0.001, control group 0.51 +/- 0.12 vs 0.39 +/- 0.19 mukat/g Hb, p < 0.01). The trace element profile of the patients showed a highly significant decrease in magnesium levels (p < 0.001) and increased venous copper levels (p < 0.05). No significant changes were found in zinc and selenium levels. The results of this study show that during chronic leg ischaemia the production of free oxygen radicals at rest is well controlled, but the activity of antioxidant enzymes seems to be impaired.