Oral administration of fructose improves jejunal villous morphology and nutrient digestion and absorption capabilities in a rat model of total parenteral nutrition

Digestive tract functions decline depending on the period of parenteral nutrition treatment, and a gradual transition to enteral nutrition as soon as possible is being encouraged. Rapid treatment via enteral nutrition is important to prevent the decline of intestinal capabilities following a parenteral nutrition state. However, the ideal nutrients leading to the recovery of intestinal functions remain unknown. We investigated what nutrient types more efficiently recover small intestinal capabilities using a rat model of total parenteral nutrition (TPN). We administered TPN conditions for 7 days with Wistar rats (male, 10 weeks old, each experiment n = 5). Selected nutrients [i.e. long-chain triglycerides, medium-chain triglycerides (MCTs), glucose or fructose] were administered orally for 3 days starting from day 8 of TPN. Morphology of the jejunal villus, mRNA expression levels for the digestion/absorption of nutrient-related genes and disaccharidases activity were markedly recovered following oral administration of all nutrients tested in this study. In particular, MCTs comprehensively and fructose specifically for mRNA expression more efficiently recovered small intestinal capabilities. Our results suggest that the difference in the chemical structure even the same kind of nutrient have an impact on the morphology and functions of the small intestine. Especially, fructose intake after TPN may be useful for the recovery of gastrointestinal functions during the transition phase to normal diet.