Beneficial effects of dietary acarbose in the streptozotocin-induced diabetic rat

Abstract

Diabetes is characterized by hyperphagia, polydipsia, polyuria, and elevations in blood and urinary glucose. It has also been documented that β-adrenergic responsiveness is reduced in diabetes. The intestinal glucosidase inhibitor, acarbose (BAY G 5421), decreases postprandial glycemia by delaying carbohydrate absorption. The purpose of this study was to evaluate the effects of chronic acarbose treatment ( 20 and 40 mg 100 g of diet ) on the metabolic and adrenergic parameters altered in streptozotocin (STZ) (50 mg/kg, intravenously [IV])-induced diabetes. Metabolic parameters were measured daily for 8 weeks. Diabetic rats were hyperphagic, polydipsic, and polyuric within 1 week of STZ treatment. Acarbose treatment did not consistently effect the food intake but did reduce water intake, urinary output, blood glucose, and the urinary loss of glucose associated with STZ-induced diabetes. Adrenergic responses were assessed by monitoring the increase in tail skin temperature (TST) associated with administration of isoproterenol. Diabetic rats were less responsive than controls and acarbose treatment restored responses toward that of the controls. Additionally, 3H-NE release from the tail artery was elevated in the diabetic rat and restored to normal in the acarbose-treated animals. Collectively these data suggest that acarbose treatment is effective in reducing the severity of metabolic and autonomic complications associated with STZ-induced diabetes.