Background: Colostrum contains a wide variety of crucial nutritional elements including growth factors for newborn infants to adapt to the extrauterine environment.
Objective: To investigate the clinical significance of epidermal growth factor receptor ligands in milk during the first month of lactation.
Methods: The concentrations of epidermal growth factor (EGF), amphiregulin (AR) and transforming growth factor-α (TGF-α) in milk sampled from a total of 31 normal mothers at days 1-3, 5, and 30 postpartum were examined using ELISA.
Results: At days 1-3, the concentration of EGF was extremely high [131.6 ± 20.4 (mean ± SEM) ng/ml] compared to that of AR (4,197.2 ± 1,055.2 pg/ml) or TGF-α (261.7 ± 33.6 pg/ml), while the concentration of AR was significantly elevated compared to that of TGF-α. At days 5 and 30, the concentration of EGF was significantly elevated compared to that of AR or TGF-α. In 16 mothers among the same 31 subjects, samples were longitudinally obtained on days 1, 2, 5, and 30 postpartum. Concentrations of AR were higher on days 1 and 2 and rapidly declined to below 1 ng/ml on day 5, and were maintained at lower levels on day 30. Concentrations of EGF were high on day 1 (greater than 10 ng/ml) but gradually declined by days 2, 5, and 30. Concentrations of TGF-α remained at lower levels of below 1 ng/ml throughout the lactation period from days 1 to 30.
Conclusion: These results suggested that EGF and amphiregulin in colostrum might contribute to the early stage of development of neonatal gastrointestinal function.