Hypoglycemic and Hypolipidemic Effects of Myrtus communis, Trachyspermum copticum and Ferula gummosa Essential Oils on Streptozotocin Induced Diabetic Rats

Background and Objectives: Diabetes is one of the major health challenges in world. Herbal medicines are widely used for the treatment of diabetes. The current study assessed the effects of oral administration of essential oils from Myrtus communis, Trachyspermum copticum and Ferula gummosa on blood glucose and lipid profiles in streptozotocin-induced diabetic rats and inhibitory effects of these oils on α-glucosidase activity in vitro. Materials and Methods: Forty-eight male Wistar rats were divided into six groups of healthy control, diabetic control, healthy control received corn oil and three experimental diabetic groups treated by the essential oils. Four weeks after intraperitoneal injections of 45-mg/kg streptozotocin doses, experimental groups were gavaged with 200 mg/kg/day of the oils for thirty days, then serum glucose and lipid profiles of the rats were assessed. Data were analyzed using one-way ANOVA and Tukey test. Study was carried out in Animal Laboratory of the Translational Ophthalmology Research Center, Tehran, Iran, 2016. Results: Compared to healthy control group, serum glucose, triglyceride (TG) total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) increased in diabetic control group significantly (P < 0.001). No significant differences were observed in high-density lipoprotein cholesterol (HDL-C) between the healthy and diabetic control groups. The M. Communis oil showed the most significant inhibitory effects on α-glucosidase than those two other oils did. Furthermore, M. communis significantly decreased glucose (478±24 vs. 355±48; p<0.001) , TG (167±13 vs. 118±13; p<0.001), TC (107±11 vs. 83±13; p<0.01), and LDL-C (70±8 vs. 47±4; p<0.001) while increased HDL-C (37±5 vs. 53±9; p<0.01). F. gummosa and T. copticum had no effect on glucose levels in diabetic rats. T. copticum lowered TC (107±11 vs. 89±12; p<0.05) and (LDL-C (70±8 vs. 43±10; p<0.001) while increased HDL-C (37±5 vs. 49±8; p<0.05). F. gummosa just decreased TG (167±13 vs. 105±12; p<0.001) and LDL-C (70±8 vs. 30±4; p<0.001) levels in diabetic rats. Conclusions: In general, lipid profile improvement was demonstrated using the three essential oils in diabetic rats; of these essential oils, only M. Communis oil included hypoglycemic effects possibly due to its α-glucosidase inhibitory activity.