Zinc Oxide Nanoparticles Show Antidiabetic Activity in Streptozotocin-Induced Type 1 and 2 Diabetic Rats

Abstract

The correlation of diabetes and an imbalance in zinc homeostasis makes zinc-based therapy an attractive proposition. In this study, zinc oxide nanoparticles were evaluated for antidiabetic effects and safety. Zinc oxide nanoparticles (1, 3 and 10 mg/kg) were tested for antidiabetic activity in streptozotocin-induced Type 1 and 2 diabetic rats. A single-dose pharmacokinetic study, cytotoxicity, hemolysis, acute and subacute toxicity tests, and mechanism-of-action studies were performed. Oral administration of zinc oxide nanoparticles resulted in significant antidiabetic effects--that is, improved glucose tolerance, higher serum insulin (70%), reduced blood glucose (29%), reduced nonesterified fatty acids (40%) and reduced triglycerides (48%). Nanoparticles were systemically absorbed resulting in elevated zinc levels in the liver, adipose tissue and pancreas. Increased insulin secretion and superoxide dismutase activity were also seen in rat insulinoma (RIN-5F) cells. Nanoparticles were safe up to a 300 mg/kg dose in rats. Zinc oxide nanoparticles are a promising antidiabetic agent warranting further studies.