Attempt to prevent the development of diabetes in non-obese diabetic mice by oral vanadate administration

Despite current treatment protocols, the long-term complications of insulin-dependent diabetes mellitus have prompted the investigation of strategies for the prevention of IDDM.

To investigate the effect of oral vanadate in reducing diabetes type I in non-obese diabetic mice.

Sodium metavanadate, 3.92 mmol/L, was added to the drinking water of 8-week-old female NOD mice. Blood glucose levels, water consumption and body weight were measured, and the end point of the study was judged by the appearance of hyperglycemia in the mice.

Treatment with vanadate did not significantly reduce the incidence of type I diabetes as compared to the control group. However, oral vanadate therapy significantly reduced the blood glucose levels after the fourth week of treatment compared to the control group (3.83 +/- 0.67 vs. 4.44 +/- 0.83 mmol/L, P < 0.03). There was a consistent and significant increase in body weight of the vanadate-treated pre-diabetic NOD mice compared to the controls. Diabetic mice treated with vanadate had significantly lower levels of serum insulin as compared to control diabetic mice (104 +/- 27 vs. 151 +/- 36 mumol/L, P < 0.03). Histologically, no significant differences were found in inflammatory response of the islets of Langerhans between the control and treated groups.

This study suggests that the post-receptor insulin-like effect induced by vanadate is not sufficient to prevent the development of diabetes and insulitis in pre-diabetic NOD mice.