The present study was aimed to evaluate the hypoglycemic properties of individual phytochemicals such as Gymnemic acid, Trigonelline and Ferulic acid as well as a polyherbal preparation (GTF-231) comprising of the above phytoingredients in the ratio of 2:3:1 in HFD fed-low dose STZ induced experimental type 2 diabetes in rats. Healthy, male Wistar rats weighing between 160-180g were used in the present study. The rats were divided into seven groups of six animals each. Group I served as control rats fed with normal pellet diet. Group II served as negative control and fed with a high fat diet for two weeks and intraperitoneally injected with a low dose of STZ (35mg/kg. b.w.) to induce experimental type 2 diabetes. Group III to V were induced with diabetes and treated with individual phytochemicals such as Gymnemic acid, Trigonelline and Ferulic acid for oral administration was fixed as 300 mg/kg.b.w./rat/day, respectively. Group VI was diabetic rats treated with polyherbal preparation at the concentration of 300mg/kg.b.w. Group VII was diabetic rats treated with metformin (200mg/kg.b.w.), a standard drug used for the treatment of type 2 diabetes. Body weight, food and fluid consumption were recorded periodically. At the end of the experimental period, the animals were starved overnight and OGTT was performed. After 30 days of experimental period, the animals were overnight fasted, anesthetized and scarified by cervical decapitation. Blood was collected with and without anticoagulants for the separation of plasma and serum, respectively. The biochemical analysis performed includes fasting blood glucose, HbA1c, plasma insulin, C-peptide and urine sugar. Insulin resistance, β-cell function and insulin sensitivity were also manipulated from HOMA-IR, HOMA β-cell function and QUICK-I index. The results of the present study clearly indicate that the polyherbal preparation as well as individual phytoingredients significantly decreased the levels of fasting blood glucose and HbA1c. Individual phytoingredients and GTF-231 improves the plasma insulin and C-peptide levels. From the arithmetic data, GTF and phytochemicals reduces the insulin resistance and enhances β-cell function and insulin sensitivity. The antidiabetic efficacy was more pronounced in rats treated with GTF-231. The results obtained clearly evidenced that the polyherbal preparation possess significant antidiabetic properties than the individual phytochemicals used in the present study indicating the synergistic effect of phytoingredients present in the polyherbal preparation.
