Cord blood ghrelin, leptin, and IGF-1: their inter-relations and relationships to gestational age, gender and anthropometrics

ABSTRACT

The main purposes of this study was to 1] compare cord blood ghrelin, leptin and IGF-1 concentrations in PT-AGA and FT-SGA infants to that of FT-AGA. 2] determine the independent contributions of these metabolic hormones to intrauterine fetal growth and infant birth size. 3] investigate their inter-relations and relationships to anthropometric parameters. 4] determine the effect of gender on cord blood hormone concentrations. We studied 75 newborns [45 males, 30 females], classified into 3 sub-groups Group A included 45 infants [25 males, 20 females], FT-AGA as controls. Their gestational ages ranged from 37-42 weeks and birth weights ranged from 2575-3930 gm. Group B included 19 infants [12 males, 7 females], PT-AGA. Their gestational ages ranged from 28-36 weeks and birth weights ranged from 1855-2350 gm. Group C included 11 infants [7 males, 4 females], FT-SGA. Their gestational ages ranged from 37-41 weeks and birth weights ranged from 2080-2650 gm. All studied newborns were subjected to a detailed history and clinical evaluation. Demographic and anthropometric characteristics, including body weight, length, HC and BMI were registered immediately after birth. At delivery, cord blood sample was collected from all studied newborns for hormonal assay of ghrelin, leptin and IGF-1. A comparative statistical analysis and correlation studies were done for anthropometric and laboratory data within and between studied groups. Ghrelin, leptin and IGF1 were detectable in cord blood of all newborns. Cord blood ghrelin concentration of group A was significantly lower than that of group B and C, while that of group B was significantly lower than that of group C. Cord blood leptin concentration of group A was significantly higher than that of group B and C, while that of group B was significantly higher than that of group C. Cord blood IGF-1 concentration of group A was significantly higher than that of group B and C, while that of group B was significantly higher than that of group C. Cord blood ghrelin, leptin and IGF-1 were significantly higher in female than in male infants. Cord blood leptin correlated positively with gestational age, birth weight, BMI and cord blood IGF-1. Cord blood ghrelin correlated negatively with birth weight, BMI and cord blood IGF-1. IGF-1 correlated positively with birth weight and BMI. Metabolic hormones, ghreiln, leptin and IGF-1 were detectable in cord blood of all newborns, even at early gestation [as early as 28 weeks gestation] Their interrelations and correlations with gestational age and anthropometric parameters suggest that these hormones are gestation related and may play an important role in energy balance and homeostasis and regulating growth in utero