Antidiabetic effects of sage (Salvia officinalis L.) leaves in normal and streptozotocin-induced diabetic rats

Background: Sage (Salvia officinalis L.) has a wide range of biological activities, such as anti-oxidative properties, anti-bacterial, hypoglycemic, anti-inflammatory, fungistatic, virustatic, astringent, eupeptic and anti-hydrotic effects. This study was designed to examine the antidiabetic effect of sage ethanolic extract in normal and streptozotocin-induced diabetic rats. Methods: Oral administration of sage extract (0.1, 0.2, and 0.4 g/kg body weight) and glibenclamide (600 mg/kg) for 14 days on the level of serum glucose, triglycerides, total cholesterol, urea, uric acid, creatinine, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in normal and streptozotocin-induced diabetic rats were evaluated. Results: Oral administration of 0.2 and 0.4 g/kg body wt. of the sage extract for 14 days exhibited a significant reduction in serum glucose, triglycerides, total cholesterol, urea, uric acid, creatinine, AST, ALT and increased plasma insulin in streptozotocin-induced diabetic rats but not in normal rats. Glibenclamide was used as reference and showed similar antidiabetic effect. Conclusions: It is concluded that the traditional use of S. officinalis as an antidiabetic agent is justified and that extracts from this plant show a dose-dependent activity which is comparable to the standard antidiabetic drug glibenclamide. (C) 2009 Published by Elsevier Ltd on behalf of Diabetes India.