Abstract
The effects of Nigella sativa L. and Cinnamomum zeylanicum Blume oils on some physiological parameters were investigated in streptozotocin (STZ)-induced diabetic male Wistar rats. STZ-induced diabetic rats showed significant increases in the levels of blood glucose, triglycerides, cholesterol, low density lipoprotein LDL-cholesterol, urea, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) while body weight, high density lipoprotein HDL-cholesterol, total protein and uric acid levels were significantly decreased compared to normal rats. Administration of the tested oils to diabetic rats resulted in a significant decrease in blood glucose, triglycerides, cholesterol, LDL-cholesterol and ALT while HDL-cholesterol level was markedly increased after three weeks compared to untreated diabetic rats. In addition, treating diabetic rats with N. sativa plus C. zeylanicum oils showed significant increases in the levels of total protein, uric acid and creatinine. In contrast, administration of C. zeylanicum oil to diabetic rats resulted in a significant decrease in ALT level compared to the untreated diabetic rats. The results of this study indicate that the tested oils possess hypoglycemic, hypolipidemic and antioxidant effects in STZ-induced diabetic rats.