title: Localization of TGF-β and TGF-β receptor in bovine term placentome and expression differences between spontaneous and induced parturition.
abstract: BACKGROUND
  Mechanisms of detachment of fetal membrane after parturition in cattle are poorly understood. Glucocorticoids trigger the initiation of parturition and may facilitate the placental maturation. We compared the disappearance of trophoblast binucleate cells (BNCs) and expression of transforming growth factor-β (TGFB) in term placentomes between spontaneous and induced parturition to investigate the influences of glucocorticoids on the placental maturity.
  
  
  METHODS
  Cows were delivered spontaneously (SP group) or after the administration of prostaglandin (PG) F(2)α (PG group); dexamethasone, PGF(2)α, and estriol (DEX group); and triamcinolone acetonide, PGF(2)α, and betamethasone (BET group) and placentomes were collected immediately after parturition. The number of BNCs in hematoxylin and eosin stained section was examined. Protein localization and mRNA levels of TGFB and its receptor (TGFBR) were analyzed using immunohistochemistry and qRT-PCR, respectively.
  
  
  RESULTS
  TGFB1 is characteristically localized in the maternal septum in caruncle in contrast to TGFB2 and TGFB3, which are mainly found in cotyledonary villi and maternal epithelial cells. TGFBR1 and TGFBR2 colocalized in BNCs. The number of BNCs was lower in the SP group than in PG and DEX groups. mRNA levels of TGFB1, TGFBR1 and TGFBR2 in the SP group differed from PG and DEX groups. There was no difference between SP and BET groups in all analyses.
  
  
  CONCLUSIONS
  These results indicate that parturition inductions using PGF(2)α or dexamethasone were not able to induce disappearance of BNCs and change of TGFB signaling. Results in the BET group suggest that investigation into types, dose, and dosage schedule of glucocorticoids may facilitate placental maturation.
authors.affiliation: Animal Biotechnology Group, Animal Research Center, Hokkaido Research Organization, Shintoku, Hokkaido 081-0038, Japan. Electronic address: hh205718@bioindustry.nodai.ac.jp.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Hirayama
authors.affiliation: Dairy Cow Group, Konsen Agricultural Experiment Station, Hokkaido Research Organization, Nakashibetsu, Hokkaido 086-1135, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Koyama
authors.affiliation: Department of Animal Science, Faculty of Agriculture, Iwate University, Morioka, Iwate 020-8550, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Sawai
authors.affiliation: Animal Biotechnology Group, Animal Research Center, Hokkaido Research Organization, Shintoku, Hokkaido 081-0038, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Fujii
authors.affiliation: Animal Biotechnology Group, Animal Research Center, Hokkaido Research Organization, Shintoku, Hokkaido 081-0038, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Naito
authors.affiliation: Animal Biotechnology Group, Animal Research Center, Hokkaido Research Organization, Shintoku, Hokkaido 081-0038, Japan.
authors.forename: Shigeo
authors.initials: S
authors.lastname: Fukuda
authors.affiliation: Animal Biotechnology Group, Animal Research Center, Hokkaido Research Organization, Shintoku, Hokkaido 081-0038, Japan.
authors.forename: Soichi
authors.initials: S
authors.lastname: Kageyama
mesh_terms: D000818:Animals; D001623:Betamethasone; D002417:Cattle; D003907:Dexamethasone; D015237:Dinoprost; D005260:Female; D005353:Fibronectins / Q000378:metabolism; D005938:Glucocorticoids / Q000494:pharmacology*; D007751:Labor, Induced; D010920:Placenta / Q000187:drug effects / Q000378:metabolism*; D011247:Pregnancy; D018125:Receptors, Transforming Growth Factor beta / Q000378:metabolism*; D047929:Term Birth; D016212:Transforming Growth Factor beta / Q000378:metabolism*; D014222:Triamcinolone Acetonide
chemical_list: D005353:Fibronectins; D005938:Glucocorticoids; D018125:Receptors, Transforming Growth Factor beta; D016212:Transforming Growth Factor beta; D003907:Dexamethasone; D001623:Betamethasone; D015237:Dinoprost; D014222:Triamcinolone Acetonide
keywords: Betamethasone; Binucleate cells; Cattle; Parturition; Placenta; TGF-beta