Therapeutic potential of vitamin D in improving antioxidant defense and blood rheology in a rat model of experimental diabetes mellitus

Objectives: To evaluate the preventive and corrective effects of vitamin D on antioxidant defense and blood rheology in rats with streptozotocin (STZ)-induced diabetes mellitus. Methods: Forty male rats (10 weeks old, ∼200 g) were randomly assigned to four groups: Group I - Intact controls; Group II - Diabetic rats (STZ only); Group III - Preventive (vitamin D for 14 days before STZ and continued throughout the experiment); Group IV - Therapeutic (vitamin D from day 3 post-STZ). DM was induced with streptozotocin (30 mg/kg), and vitamin D was administered orally at 300 IU/day, according to a previous dose-control experiment. Data from the 21st experimental day were evaluated. Blood samples collected at this point were used to determine catalase (CAT), superoxide dismutase (SOD), and blood rheological parameters. Results: Vitamin D supplementation enhanced antioxidant-related parameters and improved blood rheological indices, particularly when administered therapeutically. Conclusions: Vitamin D shows therapeutic potential in attenuating oxidative imbalance and improving blood rheology in streptozotocin-induced diabetes mellitus.