Correlates of diabetes markers with erythrocytic enzymes decomposing reactive oxygen species

catalase were assayed in the erythrocytes of a diabetic population on various treatment regimens (diet, oral therapy, and insulin), to investigate any rela-tionships between their activities and diabetes markers (serum glucose, lipids, and fructosamine, as well as glycated haemoglobin). In the group of patients as a whole, there was significant negative correlation of SOD, but not of the other two enzymes with glycated haemoglobin and fructosamine. Specifically, there was a lower activity of the enzyme in the poorly-controlled patients. It is concluded that SOD in particular is potentially an additional marker for long-term diabetic pathophysiology. Clinical chemistry is increasingly concerned with fluxes of intracellular constituents, since plasma is a reflection of cellular patho-physiology. I Among the intracellular enzymes which have attracted much attention is super-oxide dismutase (BC 1.15.1.1) which converts the toxic superoxide radical to water and hydrogen peroxide. Since SOD is also noxious, other enzymes, namely GPX (BC 1.19.1.1) and catalase (BC 1.11.1.6) are present, presumably for the complete removal of reactive oxygen species. SOD catalase superoxide) peroxide) water GPX These enzymes, and the biology of their subs-trates, have recently been the subject of a number of comprehensivereviews,a reflection of burgeoning interest in the field.2 • 3 It has been demonstrated that superoxide dismutase SOD activity in the polymorphonuc-lear leu~es of diabetic adult subjects is diminished, as it is in the lymphocytes and erythrocytes of insulin-dependent diabetic children. ' We showed that the activities of this enzyme, and GPX and catalase, were decreased by about 20 % in the erythrocytes of a group of diabetics.&quot