Glucagon-like peptide-2 in umbilical cord blood from mature infants.

Background: Glucagon-like peptide-2 (GLP-2) seems to be a highly specific intestinotrophic mediator. From animal studies, GLP-2 is known to increase in the early neonatal period before it falls to adult level. No studies in newborn infants addressing this specific subject have been published so far.

Objectives: To measure GLP-2 concentrations in umbilical cord blood from healthy mature infants and to assess any influence from the processes associated with spontaneous birth to GLP-2 production.

Subjects: Twenty-one children delivered by elective cesarean section for maternal reasons and 18 children delivered spontaneously vaginally and without complications were included. Gestational age (GA) was median (range) 38.7 (40.7-37.1) weeks and 40.2 (41.9-38) weeks, and birth weight was median (range) 3,210 (4,820-2,100) g and 3,396 (4,225-3,050) g, respectively. The infants had no diagnosed diseases or malformations.

Methods: Umbilical cord blood was collected shortly after birth. Plasma was separated and GLP-2 immunoreactivity was measured with a specific NH(2)-terminal radioimmunoassay.

Results: GLP-2 was detected in all samples. Mean values +/-SD were 16.7 +/- 3.9 pmol/l and range was 32-11 pmol/l, which is comparable to adult fasting levels. No significant correlation to birth weight (p = 0.087) or to cesarean section (p = 0.059) was found. In multiple linear regression analysis (GLP-2 vs. GA + cesarean section), neither vaginal delivery nor GA were statistically significantly related to the level of GLP-2 (p = 0.28 and 0.18), respectively.

Conclusions: GLP-2 is present in human cord blood by the time of birth. The level of GLP-2 is comparable to adult fasting levels. Spontaneous birth at most induces a minor increase in GLP-2 in term infants. In the narrow age interval studied, no significant effect of maturation was seen.