Preventive and curative effect of Trigonella foenum-graecum L. seeds in C57BL/6J models of type 2 diabetes induced by high-fat diet

Ethnopharmacological relevance: Trigonella foenum-graecum L (TFG) is traditionally used to treat diabetes in North Africa. we therefore tested the effects of the hydro-alcoholic extract of TFG seeds in a C57/BL6J mouse model of diabetes induced by a standardised high-fat diet (HFD). Materials and methods: Plant extracts (2 g/kg daily) were administered orally by gavage at the start of HFD, or after confirmation of established diabetes (17th week), for 20 or 18 weeks, respectively, to male C57BL/6J mice. Animals were weighed: food intake and plasma glucose, lipid profile, insulin and insulin resistance were measured. Results: TFG extracts opposed the development of diabetes: compared with untreated HFD mice, TFG-treated HFD mice had lower mean (+/- SD) plasma glucose (129.3 +/- 39.4 vs. 183.1 +/- 19.1 mg/dL, P < 0.05). plasma insulin (1.3 +/- 0.8 vs. 3.1 +/- 1.8 ng/mL, p < 0.05) and triglycerides (18.9 +/- 12.9 vs. 48.9 +/- 12.1 mg/dL, p < 0.05), and less insulin resistance as estimated by the homeostasis model assessment (HOMA: 9.7 +/- 11.1 vs. 38.3 +/- 26.6, p < 0.05). In mice with established diabetes, TFG reduced fasting plasma glucose (170.4 +/- 24.1 vs. 229.0 +/- 20.8 mg/dL, p < 0.05), plasma insulin (1.7 +/- 1.3 vs. 3.3 +/- 14.3 ng/mL, p < 0.05) and insulin resistance (HOMA: TFG: 19.2 +/- 15.7 vs. HFD control: 38.5 +/- 30.3, p < 0.05). In addition, administration of TFG extract also caused significant reduction in triglycerides (17.9 +/- 9.7 vs. 62.8 +/- 18.3 mg/dL, p < 0.05) and total cholesterol (1.30 +/- 0.20 vs. 1.80 +/- 1.10 g/L, P < 0.05), and an increase in HDL-cholesterol (1.6 +/- 0.2 vs. 1.2 +/- 0.1 g/L). The plant extract had no effect on calorie intake or body weight. Conclusion: TFG extract opposed the development of experimental HFD diabetes in mice, and had an anti-diabetic effect in mice with established diabetes. (C) 2012 Elsevier Ireland Ltd. All rights reserved.