Trophic effects of vanadium on beta-cells of STZ-induced insulin dependentdiabetic rats & evidence for long term relief of diabetes mellitus

The effects of one year combined vanadium and insulin treatment (VIT) on bl ood glucose levels of insulin dependent diabetic (IDD) rats were studied. R ats made diabetic by an iv injection of 55-60 mg/kg streptozotocin (STZ), d ivided into two groups and treated with a low dose of NPH insulin (2-4 U/ra t) for two months to survive from hyperglycaemic shock, In group A, hypergl ycaemia ameliorated during one year by increasing the daily dose of insulin to 8.2 +/- 0.4 U/100 g (IT) and in group B by switching over to hydrated v anadium solution (1 mg/ml vanadyl oxide sulphate pentahydrate in drinking w ater; VIT). The results of the study indicated that one year VIT regenerate d new beta-cells, and relieved diabetes both during treatment and after wit hdrawal. However, one year IT showed no trophic effects on the destroyed be ta-cells, hence no improvement in the glycaemic status of the animal was se en after withdrawal. The action of VIT was such that in group B normoglycae meia persisted in 90 per cent of diabetic rats two weeks after insulin with drawal. But in the same group, 45 days after combined vanadium and insulin withdrawal blood glucose was normal in 60 per cent of the rats, it was betw een 250-300 mg/dl in 18 per cent and between 350-400 mg/dl in 24 per cent o f the rats. In conclusion it appears that long term VIT regenerates pancrea tic beta-cells of IDD rats and possibly by improving their secretory functi ons it relieves diabetes mellitus.