Circulating ghrelin levels in the newborn are positively associated with gestational age.
OBJECTIVE
Ghrelin exerts potent GH-releasing activity and stimulates food intake. Circulating ghrelin levels are increased in anorexia and cachexia, reduced in obesity and restored by weight recovery. Newborns are characterized by GH hypersecretion associated with low IGF-I levels reflecting peripheral GH resistance.


METHODS
The aim of our study was to measure cord ghrelin levels in 117 newborns appropriate for gestational age, born either at term or preterm.


RESULTS
Ghrelin levels in cord blood (median; 25th-75th centile: 327.6; 206.0-413.0 pg/ml) were higher (P < 0.0001) than those in maternal blood at delivery (133.0; 89.0-173.7 pg/ml), without gender differences. A positive correlation between ghrelin levels in mothers and newborns (r = 0.26, P < 0.01) was observed. Ghrelin levels in newborns born at term (399.0; 229.0-438.0 pg/ml) were remarkably higher (P < 0.0001) than those in born preterm (208.0; 144.5-278.9 pg/ml). A clear positive association was present between ghrelin levels and gestational age. No association between ghrelin and GH, IGF-I, insulin, glucose and leptin levels were found.


CONCLUSIONS
Cord ghrelin levels show clear gestational age-related dependency. The lack of any direct relationship between ghrelin and anthropometric or biochemical parameters in adequate for gestational age newborns does not support the hypothesis that ghrelin has major role in foetal GH secretion and growth.
Bellone
S
S
Division of Pediatrics, Department of Medical Sciences, University of Piemonte Orientale, Novara, Italy.
Rapa
A
A
Vivenza
D
D
Vercellotti
A
A
Petri
A
A
Radetti
G
G
Bellone
J
J
Broglio
F
F
Ghigo
E
E
Bona
G
G
D000328:Adult; D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000032:analysis; D005260:Female; D005312:Fetal Blood / Q000737:chemistry*; D005865:Gestational Age; D054439:Ghrelin; D019382:Human Growth Hormone / Q000097:blood; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature / Q000097:blood*; D007328:Insulin / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D020738:Leptin / Q000097:blood; D036361:Peptide Hormones / Q000097:blood*; D011247:Pregnancy
D015415:Biomarkers; D001786:Blood Glucose; D054439:Ghrelin; D007328:Insulin; D020738:Leptin; D036361:Peptide Hormones; D019382:Human Growth Hormone; D007334:Insulin-Like Growth Factor I