Placental steroids in cattle: hormones, placental growth factors or by-products of trophoblast giant cell differentiation?
| Autor: | G. R. Özalp, Gerhard Schuler, B. Döring, H. Greven, Bernd Hoffmann, Mariusz P. Kowalewski |
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| Přispěvatelé: | Uludağ Üniversites/Veteriner Fakültesi/Kadın Hastalıkları ve Doğum Anabilim Dalı., Özalp, Gözde Rabia, AAE-3607-2019 |
| Rok vydání: | 2008 |
| Předmět: |
Molecular-cloning
Estrogen synthesis Steroidogenic enzymes Estrone sulfate Endocrinology Diabetes and Metabolism medicine.medical_treatment Placenta Giant cell Review Epithelium cell Corpus-luteum Estrone Cows Holstein-Friesian Cattle Progesterone receptor Fetal Development chemistry.chemical_compound Endocrinology Autocrine effect Placental growth factor Fetoplacental unit Estrogen receptor Estrogen receptor beta Conjugated estrogens Aromatase Gonadal Steroid Hormones Progesterone Endocrinology & metabolism Priority journal Late-gestation Trophoblast Cell Differentiation General Medicine Trophoblast giant cell differentiation Trophoblasts Cholesterol medicine.anatomical_structure Bovine placenta Estrogen-receptor-alpha Cell type Placenta development Steroid receptors Female Pregnenolone sulfate medicine.medical_specialty Steroid hormone Steryl sulfatase Functional-differentiation Down regulation Biology Estrogen sulfotransferase Upregulation Internal medicine Internal Medicine medicine Animals Estrogen Sulfotransferase Cholesterol sulfate Parturition Hormone release Cytochrome p450c17 Nonhuman Estrogen Placentation Cholesterol monooxygenase (side chain cleaving) Steroidogenesis chemistry Placenta function biology.protein Protein expression Cell nucleus receptor Cattle Progesterone production |
| Zdroj: | Experimental and clinical endocrinologydiabetes : official journal, German Society of Endocrinology [and] German Diabetes Association. 116(7) |
| ISSN: | 0947-7349 |
| Popis: | The bovine placenta produces large amounts of steroids, mainly estrone (E1) and progesterone (P-4). Specific features of bovine placental steroidogenesis are I) the expression of all enzymes needed for the production of estrogens from cholesterol in the trophoblast 2) an only marginal and temporal contribution to peripheral maternal P4 levels restricted to a period between approx. days 150-240 of gestation 3) the predominance of sulfoconjugated over free El and 4) a complementary setting of steroidogenic enzymes in the two morphologically discriminable trophoblast cell types, the uninucleated trophoblast cells (UTC) and the trophoblast giant cells (TGC). In cattle so far no definite information is available on the specific biological roles of placental estrogens and P4. However, the detection of estrogen receptors and progesterone receptors in the placentomes Suggests a role primarily as local regulators of caruncular growth, differentiation and functions. Inconsistent with a function as a caruncular growth factor is the strong evidence that in cattle placental estrogens enter the maternal compartment almost completely as estrone Sulfate (EIS), which is not active at classical nuclear receptors. Oil the other hand, E IS may be converted locally to free active estrogens via the action of steroid sulfatase (StS), which has been detected in specific parts of the bovine carancular epithelium. Alternatively or in addition, StS expression in the caruncular epithelium may serve the utilization of sulfated neutral steroid precursors (e.g. pregrienolone sulfate or cholesterol sulfate) supplied with maternal blood, thus providing free substrates for further metabolization in the adjacent trophoblast. The down-regulation of P450scc and P450c17 and the Up-regulation of 3B-HSD and aromatase during the differentiation of TGC from UTC in parallel with the up-regulation of ERE and estrogen sulfotransferase in maturing TGC suggests a function of placental estrogens primarily as auto-or intracrine regulators during this process and assigns to conjugated placental estrogens a role as inactivated by-products of TGC differentiation intended for excretion. Collectively, despite some evidence from recent studies for putative roles of placental steroids in cattle their exact functions in the bovine species remain still undefined. German Research Foundation (DFG) The Ewald and Hilde Berge Foundation |
| Databáze: | OpenAIRE |
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