Hypoglycemic activity and antioxidant potential of some medicinal plants traditionally used in Turkey for diabetes

Cydonia oblonga Mill. (Rosaceae) leaves, Helianthus tuberostis L (Asteraceae) tubers, and Album porrum L (Liliaceae) bulbs are used as a folk remedy for the treatment of diabetes and they are also consumed as food in Turkey. In the present study, the anticliabenc and antioxidant activities of the ethanol extracts of these plants were studied in normal and streptozotocin-induced diabetic rats for 5 days All extracts were administrated orally to rats at the doses of 250 and 500 mg/kg Blood glucose level was measured according to glucose oxidase method In order to determine antioxidant activity, thlobarbituric acid reactive substance (TBARS) and reduced glutathione (GSH) levels in liver, kidney, and heart tissues were measured by using spectrophotometric methods. Oral administration of Cydonia oblonga (500mg/kg) and Album pornim (500 mg/kg) extracts for 5 days in diabetic rats caused a decrease in blood glucose levels by 33.8% and 18 0%, respectively Moreover, Album porrum and Cydonia oblonga extracts induced significant alleviation on only heart tissue TBARS levels (44 6 and 45 7%), Helianthus tuberosus and Album porrum extracts showed an inhibitory effect on kidney tissue TBARS levels (24 5 and 14.8%) None of the extracts restored GSH levels in kidney, liver, and heart tissues of diabetic rats (C) 2010 Elsevier Ireland Ltd All rights reserved