Introduction: Vanadyl sulfate (vanadium) has insulin like activity and trophic effects on pancreatic beta cells in experimental-induced moderate diabetic mellitus rats. In this study, we evaluated the ultrastructure of beta cells of normal and diabetic rats and comparing effects of vanadium on the structures using TEM (transmission electron microscopy).
Method: Normal rats were assigned to three groups: Rats of group I were normal (n=12). Diabetes mellitus (blood glucose: 500-600mg/dl) was induced in rats of groups II (n=9) and III (n=10) by streptozotocin (40mg/kg). Groups I and II received tap water and in group III it was replace with vanadium solution (1mg/ml) for 60 days. Finally the animal was anesthetized and sacrificed to remove the pancreas for TEM preparation.
Results: Blood glucose remained high in diabetic rats (552±7mg/dl), whereas, in vanadium treated rats decreased by 40%. Ultra structures of beta cells of diabetic rats of group II showed chromatin clamping, low number and irregular β-granules, cytoplasm reduction, ER fragmentation, irregular mitochondrial membrane plus vacuolization and without crysta, all confirming degeneration and apoptosis of beta cells. Whereas, in vanadium treated rats of group III, these defects were restructured by increasing β-granules with dense core surrounded by an electron-lucent halo and clear membrane with normal intracellular organelles.
Conclusion: Vanadium seems to proliferate or regenerate the degenerated beta cells of Langerhans islets of diabetic rats by repairing and enhancing their intracellular organelles and possibility improve their of synthesis and storage of insulin.