Background: Partial enteral nutrition is administered to infants on parenteral nutrition to stimulate intestinal function. Herein, the hypothesis that supplementation of partial enteral nutrition with insulin-like growth factor-I would augment intestinal development was investigated.
Methods: One-day-old piglets (n = 29) were randomly assigned to five dietary treatment groups: 100% of energy as enteral formula, 100% of energy as total parenteral nutrition, or 80% parenteral nutrition/20% enteral formula supplemented with either 0, 0.2, or 1 mg/kg insulin-like growth factor-I for 7 days. Weight gain, intestinal weight, morphology, protein, and DNA content and disaccharidase activity and mRNA expression were assessed.
Results: Parenterally fed piglets had similar whole body weight gain and serum hormone concentrations but reduced intestinal mucosal weight, villus height, and sucrase and lactase activity compared with 100% enterally fed pigs. Partial enteral nutrition alone increased mucosal weight and protein content, villus height, and disaccharidase activity compared with 100% parenterally fed piglets. No effect of the lower dose of insulin-like growth factor-I (0.2 mg/kg per day) was observed, but supplementing partial enteral nutrition with 1 mg insulin-like growth factor-I/kg further increased villus width and cross-sectional area and disaccharidase activity compared with partial enteral nutrition alone. Lactase mRNA expression was not affected by insulin-like growth factor-I, suggesting that the primary site of regulation of lactase by insulin-like growth factor-I occurs after transcription.
Conclusions: Enteral insulin-like growth factor-I augmented intestinal morphology and disaccharidase activity in parenterally fed piglets over that observed with partial enteral nutrition alone. Thus enteral insulin-like growth factor-I may represent an efficacious clinical adjunct to promote intestinal development of parenterally fed neonates.