Improvement of diabetic states in streptozotocin-induced type 1 diabetic rats by vanadyl sulfate in enteric-coated capsules

• Published in: Journal of pharmacy and pharmacology Vol. 57; no. 5; p. 665
• Main Authors: Fugono, Jun, Yasui, Hiroyuki, Sakurai, Hiromu
• Format: Journal Article
• Language: English
• Published: England 01.05.2005
• Subjects: Administration, Oral; Animals; Biological Availability; Blood Glucose - analysis; Diabetes Mellitus, Experimental - blood; Diabetes Mellitus, Experimental - drug therapy; Diabetes Mellitus, Type 1 - blood; Diabetes Mellitus, Type 1 - drug therapy; Glucose Tolerance Test; Hypoglycemic Agents - administration & dosage; Hypoglycemic Agents - blood; Hypoglycemic Agents - therapeutic use; Male; Rats; Rats, Wistar; Streptozocin; Tablets, Enteric-Coated; Vanadium Compounds - administration & dosage; Vanadium Compounds - blood; Vanadium Compounds - therapeutic use
• ISSN: 0022-3573
• DOI: 10.1211/0022357055993

Chronic oral administration of vanadyl sulfate has recently been shown to improve the state of type 2 diabetic subjects. Mild gastrointestinal symptoms and side effects, however, have been observed in some subjects. To find safer and more effective dosages, we have developed an enteric-coated capsule containing solid vanadyl sulfate (ECC/VS), which enhances the bioavailability of vanadyl sulfate to almost double that of vanadyl sulfate solution. ECC/VS was chronically administered to treat streptozotocin-induced diabetic rats (STZ-rats), an animal model of type 1 diabetes mellitus, and an equivalent blood-glucose-lowering effect was observed at half the doses of vanadyl sulfate alone. In addition, we observed almost the same total vanadium levels in the serum after chronic administration of ECC/VS as those of vanadyl sulfate alone, suggesting that plasma vanadium levels correlate with the hypoglycaemic activity of vanadyl sulfate. These results indicate that oral ECC/VS improves the diabetic state by enhancing the uptake of vanadium in STZ-rats. These findings will be useful in designing clinical trials of vanadyl sulfate for diabetic subjects.