title: 11Beta-hydroxysteroid dehydrogenase type 2 in human pregnancy and reduced expression in intrauterine growth restriction.
abstract: The type 2 isoform of 11beta-hydroxysteroid dehydrogenase (11beta-HSD2), which inactivates cortisol (F) to cortisone (E), has been suggested to play a role in the ontogeny of the fetal pituitary-adrenal axis and also protect the developing fetus from the deleterious effects of circulating maternal glucocorticoids. The abundance of 11beta-HSD2 in the placenta and other fetal tissues was inferred from the F/E ratio in 17 term deliveries in both umbilical arterial (1.73 +/- 0.24, mean +/- SE) and umbilical venous blood (1.16 +/- 0.14) compared with adult peripheral venous blood (7.76 +/- 0.57, n = 70). Using sensitive assays for 11beta-HSD2 and an in-house human 11beta-HSD2 antibody, the expression and activity of this enzyme in fresh frozen human placenta increased progressively from first (8-12 weeks, n = 16) and second (13-20 weeks, n = 9) to third trimester (term) pregnancies (39-40 weeks, n = 50). Placental 11beta-HSD2 activity was significantly reduced in deliveries complicated by intrauterine growth restriction (IUGR) [25-36 weeks, n = 12, activity 380 pmol/mg/h median (225-671; 95% confidence interval)], compared with the term deliveries [888 (725-1362)] and with appropriately grown pre-term deliveries [27-36 weeks, n = 14, activity 810 (585-1269)], P < 0.05. In human pregnancy placental 11beta-HSD2 activity increases markedly in the third trimester of pregnancy at a time when maternal circulating levels of glucocorticoid are rising. The finding of attenuated placental 11beta-HSD2 activity in IUGR suggests that glucocorticoids may, in part, contribute to impaired fetal growth and that this is closely controlled in normal gestation through placental 11beta-HSD2 expression.
authors.affiliation: Department of Medicine, Queen Elizabeth Hospital, University of Birmingham, Edgbaston, UK.
authors.forename: M
authors.initials: M
authors.lastname: Shams
authors.forename: M D
authors.initials: MD
authors.lastname: Kilby
authors.forename: D A
authors.initials: DA
authors.lastname: Somerset
authors.forename: A J
authors.initials: AJ
authors.lastname: Howie
authors.forename: A
authors.initials: A
authors.lastname: Gupta
authors.forename: P J
authors.initials: PJ
authors.lastname: Wood
authors.forename: M
authors.initials: M
authors.lastname: Afnan
authors.forename: P M
authors.initials: PM
authors.lastname: Stewart
mesh_terms: D042842:11-beta-Hydroxysteroid Dehydrogenases; D005260:Female; D005317:Fetal Growth Retardation / Q000378:metabolism*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D006913:Hydroxysteroid Dehydrogenases / Q000378:metabolism*; D007150:Immunohistochemistry; D007527:Isoenzymes / Q000378:metabolism*; D007743:Labor, Obstetric / Q000378:metabolism; D010920:Placenta / Q000098:blood supply / Q000201:enzymology; D011247:Pregnancy / Q000378:metabolism*; D011264:Pregnancy Trimesters / Q000378:metabolism; D012016:Reference Values; D014469:Umbilical Arteries
chemical_list: D007527:Isoenzymes; D006913:Hydroxysteroid Dehydrogenases; D042842:11-beta-Hydroxysteroid Dehydrogenases; D006854:Hydrocortisone