title: Opposing roles of leptin and ghrelin in the equine corpus luteum regulation: an in vitro study.
abstract: Metabolic hormones have been associated with reproductive function modulation. Thus, the aim of this study was: (i) to characterize the immunolocalization, mRNA and protein levels of leptin (LEP), Ghrelin (GHR) and respective receptors LEPR and Ghr-R1A, throughout luteal phase; and (ii) to evaluate the role of LEP and GHR on progesterone (P4), prostaglandin (PG) E2 and PGF2α , nitric oxide (nitrite), tumor necrosis factor-α (TNF); macrophage migration inhibitory factor (MIF) secretion, and on angiogenic activity (BAEC proliferation), in equine corpus luteum (CL) from early and mid-luteal stages. LEPR expression was decreased in late CL, while GHR/Ghr-R1A system was increased in the same stage. Regarding secretory activity, GHR decreased P4 in early CL, but increased PGF2α , nitrite and TNF in mid CL. Conversely, LEP increased P4, PGE2, angiogenic activity, MIF, TNF and nitrite during early CL, in a dose-dependent manner. The in vitro effect of LEP on secretory activity was reverted by GHR, when both factors acted together. The present results evidence the presence of LEP and GHR systems in the equine CL. Moreover, we suggest that LEP and GHR play opposing roles in equine CL regulation, with LEP supporting luteal establishment and GHR promoting luteal regression. Finally, a dose-dependent luteotrophic effect of LEP was demonstrated.
authors.affiliation: C.I.I.S.A., Faculty of Veterinary Medicine, University of Lisbon, Portugal ; Institute of Animal Reproduction and Food Research of PAS, Olsztyn, Poland.
authors.forename: António
authors.initials: A
authors.lastname: Galvão
authors.affiliation: Department of Animal Medicine, Production and Health (MAPS), Faculty of Veterinary Medicine, University of Padua, Viale dell'Università 16, 35020 Legnaro, Padua, Italy.
authors.forename: Angela
authors.initials: A
authors.lastname: Tramontano
authors.affiliation: C.I.I.S.A., Faculty of Veterinary Medicine, University of Lisbon, Portugal.
authors.forename: Maria Rosa
authors.initials: MR
authors.lastname: Rebordão
authors.affiliation: C.I.I.S.A., Faculty of Veterinary Medicine, University of Lisbon, Portugal.
authors.forename: Ana
authors.initials: A
authors.lastname: Amaral
authors.affiliation: C.I.I.S.A., Faculty of Veterinary Medicine, University of Lisbon, Portugal.
authors.forename: Pedro Pinto
authors.initials: PP
authors.lastname: Bravo
authors.affiliation: Institute of Animal Reproduction and Food Research of PAS, Olsztyn, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Szóstek
authors.affiliation: Institute of Animal Reproduction and Food Research of PAS, Olsztyn, Poland.
authors.forename: Dariusz
authors.initials: D
authors.lastname: Skarzynski
authors.affiliation: Department of Animal Medicine, Production and Health (MAPS), Faculty of Veterinary Medicine, University of Padua, Viale dell'Università 16, 35020 Legnaro, Padua, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Mollo
authors.affiliation: C.I.I.S.A., Faculty of Veterinary Medicine, University of Lisbon, Portugal.
authors.forename: Graça
authors.initials: G
authors.lastname: Ferreira-Dias
mesh_terms: D000818:Animals; D003338:Corpus Luteum / Q000378:metabolism*; D005260:Female; D054439:Ghrelin / Q000378:metabolism*; D006736:Horses; D020738:Leptin / Q000378:metabolism*; D008263:Macrophage Migration-Inhibitory Factors / Q000378:metabolism; D054411:Receptors, Leptin / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D054439:Ghrelin; D020738:Leptin; D008263:Macrophage Migration-Inhibitory Factors; D054411:Receptors, Leptin; D014409:Tumor Necrosis Factor-alpha