Low‐glycemic index diets prevent type 2 diabetes in the Nile rat

Abstract

The Nile rat (NR) is a novel model for type 2 diabetes (T2DM) and metabolic syndrome sensitive to metabolic stress from simple carbohydrates (CHO). Three experiments assessed the effects of a low‐glycemic index CHO (green lentils, GL) on T2DM. Expt 1 compared a GL diet directly with a semipurified hiCHO diet having identical %En from CHO:fat:protein (70:10:20). Expt 2 assessed reversibility of hyperglycemia by comparing a modCHO‐GL diet (45:25:30) to diabetogenic semipurified hiCHO (70:10:20) or lab chow (#5020) diets in 3 separate studies. Expt 3 examined young Nile rats “primed” from weaning for 7wks with the modCHO‐GL diet (45:25:30) before being challenged with stressful semipurified hiCHO (70:10:20) or modCHO (40:40:20) diets based on glucose and starch. 1. Compared to the hiCHO semipurified diet with the same macronutrient composition, the GL diet induced significantly less diabetes. 2. GL substantially reversed hyperglycemia, especially in young (<4mo) diabetic rats. 3.”Priming” rats with GL prior to hiCHO resulted in less severe diabetes compared to previous studies without priming. Positive influences on other metabolic parameters such as liver and kidney weight and plasma lipids also were observed. Since the NR mimics T2DM in humans, GL or components therein may represent a potentially useful adjunct for T2DM control in humans.Funding source: Foster Biomed Res Lab and the Malaysian Palm Oil Board