Background: Although glucocorticoid hormones play important roles in fetal development, the expression of their receptors in the whole blood of preterm infants remains unknown.
Objectives: The aim of this study was to investigate the levels of glucocorticoid receptor (GR) α and β in the whole blood of preterm and term infants.
Study design: The study group consisted of 131 infants, of which 54 (41%) were preterm. Whole blood from preterm and term infants was analyzed by real-time PCR to monitor the levels of each receptor mRNA.
Results: GRβ mRNA were detected in 96.6% and GRα mRNA in 100% of participants. The GRα and GRβ isoforms were detected at a ratio of 1:0.0002. GRβ mRNA/GAPDH expression in preterm infants was significantly higher than that in term infants (p=0.002). There was significant correlation between GRα/GRβ ratio and birth weight in preterm infants (rs=0.317, p=0.019), as well as between GRβ/GAPDH expression and birth weight (rs=-0.296, p=0.030). Furthermore, in preterm infants, GRβ/GAPDH expression was higher in those with SGA than in those without SGA (p=0.022).
Conclusion: Importantly, in preterm infants, both the expression of GRβ and the GRα/GRβ ratio were associated with birth weight. Further studies with larger populations are necessary to determine the relation between the expression of GR and the clinical relevance of preterm infants.