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

The aim of the present study was to evaluate the antioxidant potential of embelin in streptozotocin-induced diabetes. 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 30 mg/kg/day for 21 days. 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. The study proves the potent antioxidant activity of embelin, which has been found to be effective in managing severe hyperglycemia.