The effect of diabetes on the activities of the peroxide metabolism enzymes.

The lipid peroxidation and (of the peroxide metabolism enzymes) the catalase, superoxide dismutase and glutathione peroxidase activities were determined in red blood cell haemolysates from 20-35-year-old human diabetics of both sexes. The results were compared with the values for normal controls from the same age group. The diabetic haemolysates displayed significantly higher glutathione peroxidase and significantly lower superoxide dismutase activities. The lipid peroxidation too was significantly higher in the diabetic haemolysates. Diabetes was induced with alloxan or streptozotocin in rats, and the enzyme activities of the blood and organ homogenates were similarly compared; in these cases the total peroxidase activity. In experimental diabetes the previously-observed phenomenon of oxidative stress was confirmed; this may serve as a logical explanation for the occurrence of the later diabetic damage.