Antioxidant activity and protection of pancreatic β-cells by embelin in streptozotocin-induced diabetes

Abstract

Objectives: The aim of the present study was to evaluate the antioxidant potential of embelin in streptozotocin-induced diabetes. Methods: Diabetes was induced in rats fasted overnight by the administration of a single dose of streptozotocin, and analyzed for blood, serum, and biological and histological pancreatic tissue parameters in intact control, diabetic, and embelin-treated diabetic rats (n=9) at the dose levels of 15, 25, and 30mg/kg/day for 21days. Results: Diabetes caused highly significant abnormalities in blood, serum, and pancreatic tissue biochemical parameters. Embelin and glibenclamide administration to diabetic rats caused a highly significant decline in the blood glycated hemoglobin and serum glucose levels and nitric oxide activity, with a concomitant increase in the serum insulin level (P<0.001). Furthermore, embelin and glibenclamide treatment increased the pancreatic antioxidant enzyme status (superoxide dismutase, catalase, reduced glutathione, glutathione peroxidase, glutathione S-transferase, and ascorbic acid), and also decreased the thiobarbituric acid reactive oxygen species contents (P<0.001). The histoarchitecture of the diabetic rats typically showed a degenerated pancreas with reduced β-cell counts, while embelin treatment was shown to significantly regenerate islet cells. Conclusion: The study proves the potent antioxidant activity of embelin, which has been found to be effective in managing severe hyperglycemia. © 2012 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and Wiley Publishing Asia Pty Ltd.