Abstract
Intrauterine growth restriction (IUGR) is associated with detrimental effects on neurodevelopmental progress in childhood and higher risk of degenerative diseases in adulthood. Placental 11β-hydroxysteroid dehydrogenase (HSD11B2) is a key gene involved in glucocorticoid metabolism, which in turn seems to be related to fetal growth impairment. As reduction of placental HSD11B2 gene expression has been associated with reduced human fetal growth, and methylation of HSD11B2 gene promoter has been shown to have an important role in HSD11B2 gene repression, we seek to investigate the relationship between IUGR and HSD11B2 gene promoter methylation in human placentas. We found that methylation levels of all studied CpG sites were significantly higher in IUGR newborns than those in controls. Further, methylation levels of the first and the third CpG sites were inversely associated with measures of fetal growth (birth weight and ponderal index). In addition, consistent with the above negative correlation, methylation levels of the first and the third CpG sites were inversely associated with HSD11B2 gene expression. These results together show a link between the site-specific methylation of placental HSD11B2 promoter and the development of IUGR.