ARS | Publication request: ORALLY ADMINISTERED IGF-I INCREASES INTESTINAL MUCOSAL GROWTH IN FORMULA-FED NEONATAL PIGS

Submitted to: Pediatric Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 10, 1995
Publication Date: N/A

Interpretive Summary: We wanted to find out what would happen if we gave formula-fed newborn pigs, by mouth, a substance called insulin-like growth factor I. We were looking for effects on the growth of the piglets small intestine. IGF-I is a growth-related substance that most mammals have in their milk. We chose the piglet for our study because it is the ideal animal model for a human infant. The result was a significant increase in growth of the small intestine. Therefore, we think providing the same therapy to newborn human babies might be a good treatment to increase their small-intestinal growth. This is groundbreaking material, because it is the first time a study has shown a definite, significant effect of any oral dose level of IGF-I on newborns' intestinal growth.

Technical Abstract: Our objective was to determine the potentially anabolic effects of orally administered recombinant human insulin-like growth factor I (rhIGF-I) on small-intestinal growth in formula-fed neonatal pigs. Unsuckled neonatal pigs received formula or formula containing added rhIGF-I (3.5 mg ùkg-1 ùd- 1) from birth to 4 days of age. Pigs in both groups were fed 30 ml/kg formula every 2 h on day 1 and then every 4 h on days 2-4, and blood was sampled daily. Oral administration of rhIGF-I to formula-fed neonatal pigs increased small-intestinal weight, protein and DNA content, but not length. Jejunal and ileal villus height, but not crypt depth or muscularis thickness, also were increased by oral rhIGF-I administration. Neither the circulating IGF-I concentration or the abundance of IGF-binding proteins differed between control and oral rhIGF-treated pigs, suggesting that the absorption of orally administered rhIGF-I from the intestinal lumen into the peripheral circulation was limited. Our results demonstrate that oral administration of rhIGF-I during the first 4 days after birth significantly increased small-intestinal mucosal growth in formula-fed neonatal pigs. These results suggest that oral administration of rhIGF-I may be a viable therapeutic approach to enhance intestinal growth in neonates.