The antidiabetic and antioxidative effect of osajin was monitored under the conditions of alloxaninduced diabetes mellitus in an in vivo experiment. The animals were divided by random selection into 2 groups (n=7). The treated group was administered osajin in peroral doses of 10 mg/kg in Avicel, the placebo diabetic group was given only the solution of Avicel, and the last group was intact. Selected laboratory parameters (glucose, urea, cholesterol, antioxidative enzymes, total antioxidative capacity, malondialdehyde in serum, diuresis, total glucose and protein losses through urine) were determined in all animals. Kidney tissue and pancreas samples were taken for histopathological analysis. The findings included a statistically significant increase (p≤0.05) in the glutathione peroxidase catalytic activity, total antioxidative capacity (p≤0.01) and a statistically significant decrease (p≤0.01) on malondialdehyde level in the treated group compared to the placebo group. A statistically highly significant decrease (p≤0.01) in diuresis, glucose and protein losses through urine were identified in the treated group compared to the placebo group. The superoxide dismutase catalytic activity, urea and cholesterol levels involved non-significant changes. The results of biochemical examination show a protective antidiabetic and antioxidative effect of osajin. The results of histopathological examination correlate with them only partially.

        Key words: osajin – diabetes mellitus – antioxidants