Epidermal growth factor (EGF) is present in milk from various mammalian species, but its physiologic function in neonatal development remains unclear. Transforming growth factor-α (TGF-α) is a peptide structurally related to EGF, and its presence is detected in the developing small intestine of rats. The purpose of the present study was to examine the effect of milk-borne EGF on endogenous production of EGF and TGF-α in the small intestine of suckling rats. Neonatal rats were fed via gastrostomy either growth factor-free rat milk substitute (RMS) or RMS supplemented with EGF (100 ng/mL of RMS) from 8 to 12 d of age. Artificially reared rats were then compared with their dam-fed littermates. Animals fed the EGF-deficient diet RMS had markedly increased EGF and TGF-α mRNA levels in duodenum and ileum compared with dam-fed controls and significantly elevated total intestinal content of TGF-α peptide. Intestinal EGF content and EGF serum levels were significantly decreased in the RMS group compared with controls. The addition of EGF to the RMS diet normalized TGF-α mRNA levels in the duodenum and ileum, EGF mRNA levels in the ileum, and total intestinal TGF-α content and EGF serum levels to the levels measured in dam-fed littermates. Motility studies showed that enteral administration of EGF did not affect stomach emptying and intestinal transit. These studies indicate that exogenous milk- borne EGF modulates endogenous production of TGF-α in developing small intestine. It is likely that neither TGF-α nor EGF are solely responsible for small intestinal overgrowth of artificially reared neonatal rats.
|Original language||English (US)|
|Number of pages||7|
|State||Published - Feb 2000|
ASJC Scopus subject areas
- Pediatrics, Perinatology, and Child Health