Leptin in the canine uterus and placenta: possible implications in pregnancy

Reproductive Biology and Endocrinology

Research

Livia P Staub¹  Orsolya Balogh¹  Iris M Reichler¹  Aykut Gram²  Mariusz P Kowalewski²  Alois Boos² 

[1] Clinic of Reproductive Medicine, Vetsuisse-Faculty, University of Zurich, Winterthurerstrasse 260, 8057, Zurich, Switzerland;Institute of Veterinary Anatomy, Vetsuisse-Faculty, University of Zurich, Winterthurerstrasse 260, 8057, Zurich, Switzerland;

关键词: Leptin;    Leptin receptor;    Dog;    Gestation;    Uterus;    Placenta;    Immunohistochemistry;    In situ;   

DOI  :  10.1186/s12958-015-0003-6

 received in 2014-10-06, accepted in 2015-02-06,  发布年份 2015

来源: Springer

【 摘 要 】

BackgroundLeptin (Lep) is known for its involvement in the regulation of reproductive functions. It is important for uterine receptivity, implantation, placental growth and maternal energy homeostasis in several species, but Lep’s function in the pregnant dog has not been investigated.MethodsPregnant bitches were ovariohysterectomized at pre-implantation, post-implantation, mid-gestation and prepartum luteolysis. Two additional groups were treated with aglepristone in mid-gestation, and ovariohysterectomized 24 or 72 h later. Lep and leptin receptor (LepR) gene expression was detected by semi-quantitative real-time PCR in pre-implantation and inter-placental uterine sections (Ut) and in utero-placental compartments (Ut/Pl). Immunohistochemistry and in situ hybridization (ISH) were performed for Lep and LepR protein and mRNA localization. Parametric one-way ANOVA, paired t-test and Wilcoxon signed-rank test were used for statistical analysis.ResultsIn the Ut/Pl, Lep expression was higher at post-implantation and prepartum luteolysis than at mid-gestation, while in the Ut, Lep mRNA levels did not change during pregnancy. LepR expression in the Ut/Pl was up-regulated at prepartum luteolysis compared to the earlier stages. In the Ut, highest LepR mRNA was found at pre- and post-implantation. LepR expression was down-regulated in the Ut/Pl compared to the Ut at post-implantation and at mid-gestation. Aglepristone treatment resulted in a decrease of Lep mRNA levels from 24 to 72 h in the Ut without concomitant changes in the Ut/Pl or in LepR levels. Lep and LepR immunoreactivities were strong in the luminal and glandular epithelium in the Ut with abundant LepR signals in the subepithelial stroma. In the Ut/Pl, fetal trophoblasts stained stronger for Lep and LepR than decidual cells, and signals for both proteins were also detected in the glandular chambers. The myometrium, blood vessel media, and sporadically also the endothelium stained for Lep and LepR. ISH showed similar signal distribution in the Ut and Ut/Pl.ConclusionsLep and LepR are differentially expressed in the canine uterus and placenta during pregnancy, and their presence in various cell types indicates paracrine/autocrine roles. The Lep signaling system may be one of the pathways involved in feto-maternal cross-talk, implantation and maintenance of pregnancy, and may have a regulatory role around parturition.

【 授权许可】

CC BY   
© Balogh et al.; licensee BioMed Central. 2015