Background: Diabetes mellitus (DM) is a cluster of metabolic diseases with chronic hyperglycemia as a defining feature, associated with long-term organ damage and dysfunction. In this study we examined the effect of Tulbaghia violacea rhizome methanolic extract on blood glucose and lipids in normal and streptozotocin-induced diabetic rats.
Materials and methods: Male Wistar rats (250-300g) were injected intraperitoneally (i.p.) with streptozotocin (60mg/kg body weight) to induce diabetes; or provided with distilled water for the control (CON) (3 ml/kg/b.w.) animals and treatment with TVL (60mg/kg.b.w). The rats were divided into 5 groups of 6 animals per group as follows: Non-diabetic control (NDC)-received distilled water (3ml/kg.b.w), Non-diabetic TVL (ND+TVL)-received TVL (60mh/kg b.w), Diabetic control (DC)-received distilled water (3ml/kg.b.w), Diabetic experimental (D+TVL)-received TVL (60mg/kg.b.w), Diabetic experimental (D+M)-received Metformin (250 mg/kg.b.w). All doses were administered daily via oral gavage.
Results: TVL-treated animals showed reduced blood glucose, increased plasma insulin, reduced plasma TG, TC, VLDL and increased HDL. Furthermore we found decreased thiobarbituric acid reactive substances (TBARS) and increased superoxide dismutase (SOD) activity and nitric oxide significantly. Regarding renal parameters we found increased blood urea nitrogen (BUN), and improved renal morphology in TVL-treated animals.
Conclusion: Tulbaghia violacea has a hypoglycaemic effect which could due to its effects on multiple pathways of the hyperglycemic process. Further work is needed to identify the mechanism of its antidiabetic effect.
Keywords: STZ-induced diabetic rats; Tulbaghia violacea; hypoglycemic activity.