title: Placental 11 β-hydroxysteroid dehydrogenase type 2 (11β-HSD2) expression very early during human pregnancy.
abstract: Maternal physiologic stress during gestation has been reported to be associated with negative developmental outcomes, including intra-uterine growth restriction and reduced birth weight, which can impact postnatal development, behavior and health. The human fetus is partially protected from elevated cortisol exposure by placental 11 β-hydroxysteroid dehydrogenase type 2 (11β-HSD2), which oxidizes bioactive cortisol into bio-inactive cortisone. Importantly, despite the critical protective role hypothesized for 11β-HSD2, the onset of its placental expression has yet to be clearly established. To this aim, we present immunocytochemical analysis of placentas collected 3-6 weeks post-conception. 11β-HSD2 was present as early as 3 weeks post-conception in syncytiotrophoblasts, where most maternal-fetal exchange occurs, and in columnar epithelial cells encircling uterine endometrial glands, which provide early histiopathic nutrition to the embryo. 11β-HSD2 expression in these critical maternal-fetal exchange areas is consistent with its hypothesized protective role. Future studies should investigate the mechanisms that may modulate embryonic glucocorticoid exposure earlier, immediately post-conception.
authors.affiliation: 1Maternal and Child Health Lab, Faculty of Health Sciences,Simon Fraser University,Burnaby,BC,Canada.
authors.forename: K G
authors.initials: KG
authors.lastname: Salvante
authors.affiliation: 3Department of Obstetrics,Gynecology and Reproductive Sciences,Yale University,New Haven,CT,USA.
authors.forename: K
authors.initials: K
authors.lastname: Milano
authors.affiliation: 3Department of Obstetrics,Gynecology and Reproductive Sciences,Yale University,New Haven,CT,USA.
authors.forename: H J
authors.initials: HJ
authors.lastname: Kliman
authors.affiliation: 1Maternal and Child Health Lab, Faculty of Health Sciences,Simon Fraser University,Burnaby,BC,Canada.
authors.forename: P A
authors.initials: PA
authors.lastname: Nepomnaschy
mesh_terms: D043209:11-beta-Hydroxysteroid Dehydrogenase Type 2 / Q000378:metabolism*; D005260:Female; D005865:Gestational Age; D006801:Humans; D008431:Maternal-Fetal Exchange; D010920:Placenta / Q000201:enzymology*; D011247:Pregnancy
chemical_list: D043209:11-beta-Hydroxysteroid Dehydrogenase Type 2
keywords: 11 β-hydroxysteroid dehydrogenase type 2 (11β-HSD2); cortisol; peri-conception; placenta; syncytiotrophoblast