Ingestion of guar gum hydrolysate, a soluble and fermentable nondigestible saccharide, improves glucose intolerance and prevents hypertriglyceridemia in rats fed fructose

Fructose feeding provides a dietary model of insulin resistance accompanied by hypertriglyceridemia. We examined the effects of guar gum hydrolysate (GGH), a soluble and fermentable nondigestible saccharide with low viscosity, on glucose intolerance and hypertriglyceridemia in rats fed high-fructose diets. Rats were fed either a dextrin-based or a fructose-based diet with or without GGH (75 g/kg) for 30 d. Oral glucose tolerance tests (OGTTs) were performed 0, 14, and 28 d after feeding. High-fructose feeding negatively affected glucose tolerance on d 14 and 28. The addition of GGH to the diets improved glucose intolerance on d 28. Fructose feeding induced hyperinsulinemia after an oral glucose load; this was also improved by GGH on d 28. The glycogen concentration in the gastrocnemius muscles of rats was lowered by dietary fructose, and GGH supplementation abolished this decrease. Triglycerides in the plasma and livers of rats fed fructose diets were elevated, and the increases were ameliorated by supplemental GGH. Regardless of the type of carbohydrate, GGH enlarged the cecum and increased the cecal SCFA pools. In conclusion, supplemental feeding of GGH to rats improved the glucose intolerance and hypertriglyceridemia induced by a high-fructose diet. Possible mediators of these beneficial effects of GGH are the SCFAs produced by microbial fermentation of GGH in the large intestine.