OXIDATIVE STRESS IN DIABETES MELLITUS
Biophysics group, Department of Biochemistry, National Research Centre, Dokki, Cairo, Egypt
Abstract. Our aim was to evaluate oxidative stress in diabetes mellitus by the measurement of biophysical parameters (changes) of hemoglobin macromolecule and some biochemical parameters on two groups of diabetic patients, non-insulin dependent diabetes mellitus (NIDDM), and insulin-dependent diabetes mellitus (IDDM). This study has been conducted on 45 NIDDM, 30 IDDM, compared to 20 healthy subjects. Blood glucose, glycosylated hemoglobin (HbA1c), fructosamine, plasma insulin, plasma malondialdehyde (MDA), erythrocyte reduced glutathione (GSH), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and glutathione reductase (GSH-Red) were measured. Also the biophysical parameters, electrical conductivity of hemoglobin, auto-oxidation rate of hemoglobin, and hemoglobin derivatives were measured. Diabetic patients (NIDDM, IDDM) have significant increases in blood glucose, glycosylated (HbA1c), fructosamine with a concomitant signifant decrease in Plasma insulin compared to control. Diabetic patients (NIDDM, IDDM) have a significant high level of MDA compared to control. Diabetic patients (NIDDM, IDDM) have a significant increase in SOD activity, and a significant decrease of GSH compared to control. Significant increases in electrical conductivity of Hb, hemoglobin auto-oxidation rate and hemoglobin derivatives in diabetic patient compared to control. IDDM have a higher level of hemoglobin auto-oxidation rate when compared to NIDDM. Diabetic patients undergo an important oxidative stress that is low in NIDDM compared to IDDM, suggesting metabolic differences between the two types of diabetes. Met-Hb is an important indicator for oxidative stress in diabetes.
Key words: IDDM, NIDDM, electrical conductivity, hemoglobin, SOD, MDA, GSH.