METABOLIC EFFECTS OF TULBAGHIA VIOLACEA HARV. IN A DIABETIC MODEL.

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

Apoptosis-inducing effects of <i>Tulbaghia violacea</i> Harvmethanolic extracts on human Jurkat leukemia T cells

51-58The aim of the present study was to investigate the effects of methonolic extracts of Tulbaghia violacea (TVL), on Jurkat cells (human T lymphocyte). Jurkat cells were treated with IC50 concentrations of TVL (leaf, rhizome and stalk) extracts as determined by MTT assay and glutathione (GSH) concentration was measured using the GSH-Glo assay. The comet and DNA fragmentation assays were used to determine DNA damage induced by the TVL extracts, and mitochondrial membrane potential activity performed by JC-1assay. The results showed that all TVL extracts except leaf increased apoptosis. TVL leaf instead showed increased necrosis when compared to other TVL components. In addition, TVL extracts induced caspase 3/7, 8 and 9 activity and induced PARP cleavage. These findings suggest that TVL exerts anti-cancer activity primarily through the mechanism of apoptosis. The results suggest that TVL rhizome and stalk induce apoptosis through the intrinsic pathway due to increased activation of caspase 9 and 3/7, with TVL rhizome having the greatest effect on human T lymphocyte cells. Thus, this study suggest that TVL extracts have the potential to induce cell death in Jurkat cells by mitochondria mediated pathway through the involvement of caspase-3/7 in particularly in TVL rhizome