Background:Critical ischemia leads to the production of reactive oxygen species (ROS) at concentrations exceeding the body’s antioxidant capacity, causing inflammation and necrosis in ischemic tissues. The protein CO group content is presently the most general indicator and commonly used marker of protein oxidation. The aim of the present study was to evaluate the concentration of serum CO groups as an effect of protein oxidative damage, and relate it to the activity of ceruloplasmin (Cp).Material/Methods:The study group consisted of 12 patients, males 43–73 years of age, with chronic arterial occlusion of the lower limbs (AO). Serum carbonyl groups were measured using reaction with dinitrophenylhydrazine (DNPH), leading to the formation of stable hydrazone products. The oxidase activity of ceruloplasmin in serum was measured according to the spectrophotometric method of Schosinsky by using o-dianisidine dihydrochloride as a substrate.Results:The average value of concentration of CO groups in subjects with AO was found to be significantly higher than in the control group. The changes in the concentration of CO groups during postoperative treatment were negatively and significantly correlated with the value found before surgery. The average oxidase activity of Cp was found to be significantly higher than in the controls.Conclusions:Prolonged ischemia of the lower limbs of patients with chronic arterial occlusion causes increased concentration of protein CO groups in serum, as the result of the oxidative modification of protein side chains, and in the oxidase activity of Cp, due to acute phase reaction.

Keywords: Ischemia - blood, Lower Extremity - blood supply, Arterial Occlusive Diseases - therapy, Blood Proteins - chemistry, Ceruloplasmin - metabolism, Ischemia - therapy, Lower Extremity - surgery, Oxidation-Reduction, Reactive Oxygen Species - metabolism