Effect of cholecalciferol supplementation on blood glucose in an experimental model of type 2 diabetes mellitus in spontaneously hypertensive rats and Wistar rats.

Background: Vitamin D might have an influence on glucose concentrations, due to the presence of VDR receptors on the pancreas. We established an experimental model of type 2 diabetes in spontaneously hypertensive rats (SHR) and Wistar rats in order to investigate the glycemic response.
Methods: SHR males (n=6) and Wistar rats (n=6) weighing approximately 89+/-5.5 g and 123.5+/-6.5 g, respectively, after 7 days of basal period, had the chow pattern substituted (350 kcal/100 g) for a hypercaloric/hyperlipidic (HC/HL) diet (490 kcal/100g) and then injected with 40 mg/kg (SHR) and 20 mg/kg (Wistar) streptozotocin I.P. After the creation of diabetes, the rats suffered daily gavage of cholecalciferol (12.5 microg/kg(-) (1)) for 14 days. The blood glucose was assessed twice a week with a glucometer. The data were analyzed by ANOVA.
Results: SHR and Wistar rats fed on a HC/HL diet gained 60 g and 32 g in once week, vs. the basal period, where they only gained 23 g and 13 g, respectively. The cholecalciferol supplementation did not change the glucose concentration in all of the SHR animals. About 40% of the group responded by treatment with reduction of about 60% in glucose concentrations. We did find a 40% of the blood glucose levels in all Wistar rats.
Conclusions: Cholecalciferol is able to reduce blood glucose in this experimental diabetes model.