Corticosteroid metabolism in human granulosa-lutein cells

• Published in: Clinical endocrinology (Oxford) Vol. 48; no. 4; pp. 509 - 513
• Main Authors: THOMAS, F. J, THOMAS, M. J, TETSUKA, M, MASON, J. I, HILLIER, S. G
• Format: Journal Article
• Language: English
• Published: Oxford BSL Blackwell Science Ltd, UK 01.04.1998; Blackwell
• Subjects: 11-beta-Hydroxysteroid Dehydrogenases; Biological and medical sciences; Birth control; Cells, Cultured; Chorionic Gonadotropin - therapeutic use; Cortisone - metabolism; Dexamethasone - metabolism; Embryo Transfer; Female; Fertilization in Vitro; Follicular Phase - physiology; Granulosa Cells - enzymology; Gynecology. Andrology. Obstetrics; Humans; Hydrocortisone - metabolism; Hydroxysteroid Dehydrogenases - metabolism; Luteal Cells - enzymology; Medical sciences; Sterility. Assisted procreation; Treatment Outcome; Human; Corticosteroid; Enzyme; Assisted procreation; Lutein; Exploration; Metabolism; Ovulation; In vitro fertilization embryo transfer; Enzymatic activity; 11β-Hydroxysteroid dehydrogenase; Female; Oxidoreductases; Granulosa; Ovarian follicle
• ISSN: 0300-0664; 1365-2265
• DOI: 10.1046/j.1365-2265.1998.00457.x

OBJECTIVE The aims of this study were to determine the type and level of 11β‐hydroxysteroid dehydrogenase (11βHSD) in human granulosa‐leutein cells (GLE) shortly before ovulation and to correlate activity with the outcome of treatment in patients undergoing in vitro fertilization and embryo transfer (IVF/ET). DESIGN GLC from 32 patients undergoing IVF/ET were tested for type and level of 11βHSD activity in relation to treatment outcome. PATIENTS Periovulatory follicles were aspirated by ultrasound guided transvaginal puncture following a standard controlled ovarian stimulation protocol, ∼36 h after administering an ovulation‐inducing dose of human chorionic gonadotrophin (HCG). GLC were separated from follicular fluid by density‐gradient centrifugation and taken for measurement of 11βHSD activity in vitro; oocytes were used for IVF/ET. MEASUREMENTS Interconversion of cortisol (F) and cortisone (E), and dexamethasone (D) and 11‐dehydrodexamethasone (DHD) was measured in standardized assays comprising incubation of GLC with 3H‐labelled substrate, with separation of substrate and product by thin‐layer radiochromatography. RESULTS Conversion of F to E varied from 10.5 to 30.9% while that of E to F was between 2.4 and 44.6%. In the GLC of 25 patients in whom both activities were measured, dehydrogenase (F to E) activity predominated in 13 and reductase (E to F) in 12. By contrast, D (substrate for 11βHSD2 but not 11βHSD1) showed less than 1% metabolism in this system while DHD (substrate for 11βHSD1 and 11βHSD2) was converted significantly (65.6–90.5%) to D in the four patients tested. There was no significant difference in the interconversion of F and E between patients who became pregnant and those who did not. CONCLUSIONS The dehydrogenase and oxoreductase reactions catalysed by 11βHSD both occur in granulosa‐lutein cells at the time of follicular rupture, probably due to 11βHSD1. A lack of measurable conversion of dexamethasone to 11‐dehydrodexamethasone suggests that dehydrogenation due to 11βHSD2 is low or absent. Neither type nor level of 11βHSD activity measured under the present assay conditions correlates with IVF outcome.