Physiological changes in maternal cortisol do not alter expression of growth-related genes in the ovine placenta

• Published in: Placenta (Eastbourne) Vol. 31; no. 12; pp. 1064 - 1069
• Main Authors: Jensen, E.C, Rochette, M, Bennet, L, Wood, C.E, Gunn, A.J, Keller-Wood, M
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.12.2010; Elsevier
• Subjects: 11-beta-Hydroxysteroid Dehydrogenase Type 1 - metabolism; 11-beta-Hydroxysteroid Dehydrogenase Type 2 - metabolism; Angiotensin receptor; Animals; Biological and medical sciences; Cortisol; Embryology: invertebrates and vertebrates. Teratology; Female; Fetal Development; Fundamental and applied biological sciences. Psychology; Gene Expression; Hydrocortisone - metabolism; Insulin-like growth factor; Internal Medicine; Obstetrics and Gynecology; Placenta - metabolism; Placentomes; Pregnancy - metabolism; Receptor, Angiotensin, Type 1 - metabolism; Receptor, Angiotensin, Type 2 - metabolism; Receptors, Glucocorticoid - metabolism; Receptors, Mineralocorticoid - metabolism; Sheep; Somatomedins - metabolism; Cortisol; Angiotensin receptor; Insulin-like growth factor; Placentomes; Corticosteroid; Fetal membrane; Steroid hormone; Growth; Antiinflammatory agent; Gene expression; Hydrocortisone; Glucocorticoid; Vertebrata; Mammalia; Placenta; Mother; Animal; Adrenal hormone; Sheep; Artiodactyla; Ungulata
• ISSN: 0143-4004; 1532-3102
• DOI: 10.1016/j.placenta.2010.09.010

Abstract Objectives The aim of this study was to investigate the effect of cortisol on growth-related genes in the ovine placenta. Study design Ewes carrying singleton pregnancies were operated on between 112 and 116 days of gestation (115 ± 0.4, term = 147 days) and randomly assigned into three groups: six control animals, five ewes that were administered cortisol by continuous intravenous infusion (1 mg/kg/day, high cortisol ), and five ewes that were adrenalectomized and replaced with 0.5–0.6 mg cortisol/kg/day and 3 μg aldosterone/kg/day to produce cortisol concentrations equivalent to pre-pregnancy values ( low cortisol ). At necropsy (130 ± 0.2 days of gestation), placental tissue was frozen and stored at −80 °C for mRNA analysis. Main outcome measures To assess potential molecular mechanisms by which cortisol alters placental structure and function and fetal growth. Results Cortisol levels did not significantly affect 11β-hydroxysteroid dehydrogenase 1 and 2 enzymes, glucocorticoid receptor, mineralocorticoid receptor and angiotensin II receptor, type 1 (AT1R) expression levels. Gene expression levels of AT2R were increased in the high cortisol group for type B placentomes. There was little effect of cortisol on the insulin-like growth factor (IGF) axis. There was significantly more IGF-I mRNA in B versus A type and more IGFBP-2 mRNA in B and C type versus A type placentomes regardless of treatment ( p  < 0.05). Conclusions These data suggest that cortisol increases placental AT2R expression at high concentrations whereas it has little effect on the placental IGF axis.