BackgroundGlucagon-like peptide 1 (GLP-1) is an incretin hormone that stimulates glucose-induced insulin secretion, increases β-cell proliferation, neogenesis and β-cell mass. In adults, plasma concentrations of amidated GLP-1 are typically within the 5–10 pmol/l range in the fasting state and increases to ∼50 pmol/l after ingestion of a mixed meal.Research design and methodsWe measured plasma glucose, insulin and amidated forms of GLP-1 prefeed and then at 20 and 60 min post-feed following

more »

... stion of a 60–70 ml of standard milk feed in preterm (n=10, 34–37 weeks) and term newborn infants (n=12, 37–42 weeks). Reverse-phase fast protein liquid chromatography was used to characterise the molecular nature of the circulating GLP-1.ResultsMean birth weight was 3.18 kg and mean age at sampling for GLP-1 was 7.7 days. The mean basal GLP-1 concentration was 79.1 pmol/l, which increased to 156.6 pmol/l (±70.9, P<0.001) and 121.5 pmol/l (±59.2) at 20 and 60 min respectively. Reverse-phase chromatography analysis suggested that the majority of GLP-1 immunoreactivity (>75%) represented GLP-1 (7–36) amide and (9–36) amide.ConclusionsBasal and post-feed amidated GLP-1 concentrations in neonates are grossly raised with the major fractions of circulating GLP-1 being (7–36) amide and (9–36) amide. Elevated GLP-1 concentrations in the newborn period may have a role in regulating maturation of enteroendocrine system and also of increasing pancreatic β-cell mass and regeneration. The high levels of GLP-1 may be due to immaturity of the dipeptidyl peptidase IV and or lower glomerular filtration rate in the neonatal period. Further studies are required to understand the role of GLP-1 in the neonatal period.