Antidiabetic effect of hydroethanolic extract of Crocus sativus stigmas, tepals and leaves in streptozotocin-induced diabetic rats

The present study investigated for the first time, the antihyperglycemic effect of tepals and leaves of Crocus sativus in streptozotocin-induced diabetic rats. The effect of these by-products were compared with that of saffron stigma and glibenclamide. Hydroethanolic extracts (stigmas, tepals and leaves) and glibenclamide were administered orally in aqueous solution daily for 21 days. In the present study, 36 male rats were used. Six rats were used in each group. Group 1: normal control rats (N), received distilled water; group 2: diabetic control rats (D), received distilled water; group 3: treated diabetic rats (TPL), received tepal (TPL) extract; group 4: treated diabetic rats (STG), received stigma (STG) extract; group 5: treated diabetic rats (LF), received leaf (LF) extract and group 6: treated diabetic rats (GLB), received glibenclamide (GLB). Blood glucose, body weight, water intake, urine elimination, plasma triglycerides, cholesterol, urea, creatinine, aspartate amino transferase (AST) and alanine amino transferase (ALT) levels were evaluated. The present data indicated that the tepals and stigmas extracts significantly prevented decreasing body weight and protected against elevation of water intake, urine elimination, blood glucose, plasma triglycerides, cholesterol, urea, creatinine, AST and ALT levels in treated diabetic rats as compared to untreated diabetic rats. Leaves extract significantly prevented decreasing body weight. It decreased water intake, blood glucose, plasma triglycerides, cholesterol, creatinine, AST and ALT. Based on our data, the oral administration of tepals, stigmas and leaves extract of Crocus sativus reduces blood glucose levels and improves control of diabetes complications.