Effects of Three Medicinal Plants Extracts in Experimental Diabetes: Antioxidant Enzymes Activities and Plasma Lipids Profiles in Comparison with Metformin

In the present study we aimed to evaluate the effects of methanolic extracts of the bulbs of Garlic (Allium sativum L., Alliaceae) and Persian shallot (Allium ascalonicum L., Alliaceae ) and leaves of Sage (Salvia officinalis L., Lamiaceae ), ASE, AAE and SOE respectively, on the antioxidant enzymes such as superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT) activities and on the levels of plasma lipids profiles such as triglycerides (TG), total cholesterol (TC), high-density lipoproteins (HDL), low-density lipoproteins (LDL) and very low-density lipoproteins (VLDL) in Alloxan diabetic Wistar rats. In comparison with diabetic control rats in diabetic treated rats, AAE increases the activities of SOD (65%), GPX (43%) and CAT (55%). ASE and SOE increase SOD activity by 60% and 33% respectively. ASE reduces TC (34%), SOE decreases TG (40%) and LDL (30%) and AAE reduces VLDL (24%). Metformin exhibits mild antioxidant and hypolipidemic properties. Results of quantitative phytochemical analysis show that the methanolic garlic and Persian shallot bulbs extracts contain secondary metabolites including alkaloids (3.490% and 3.430%), glycosides (18.023% and 13.301%) and saponins (0.812% and 0.752%). Methanolic sage leaves extract contains flavonoids (1.014%), glycosides (23.142%) and saponins (2.096%). The total phenolic contents of ASE, AAE and SOE were in order 4.273, 3.621 and 6.548 mg GAE/g dry weight (DW). These results suggest that Allium sativum, Allium ascalonicum and Salvia officinalis are beneficial in the control of diabetes by noticeable antioxidant and hypolipidemic properties.