Synergistic action of estradiol and PGE2 on endometrial transcriptome in vivo resembles pregnancy effects better than estradiol alone†

Abstract

Successful pregnancy establishment in mammals depends on numerous interactions between embryos and the maternal organism. Estradiol-17β (E2) is the primary embryonic signal in the pig, and its importance has been questioned recently. However, E2 is not the only molecule of embryonic origin. In pigs, prostaglandin E2 (PGE2) is abundantly synthesized and secreted by conceptuses and endometrium. The present study aimed to determine the role of PGE2 and its simultaneous action with E2 in changes in porcine endometrial transcriptome during pregnancy establishment. The effects of PGE2 and PGE2 acting with E2 were studied using an in vivo model of intrauterine hormone infusions, and were compared to the effects of E2 alone and conceptuses’ presence on day 12 of pregnancy. The endometrial transcriptome was profiled using gene expression microarrays followed by statistical analyses. Downstream analyses were performed using bioinformatics tools. Differential expression of selected genes was verified by quantitative PCR. Microarray analysis revealed 2413 differentially expressed genes (DEGs) in the endometrium treated simultaneously with PGE2 and E2 (P < 0.01). No significant effect of PGE2 administered alone on endometrial transcriptome was detected. Gene ontology annotations enriched for DEGs were related to multiple processes such as: focal adhesion, vascularization, cell migration and proliferation, glucose metabolism, tissue remodeling, and activation of immune response. Simultaneous administration of E2 and PGE2 induced more changes within endometrial transcriptome characteristic to pregnancy than infusion of E2 alone. The present findings suggest that synergistic action of estradiol-17β and PGE2 resembles the effects of pregnancy on endometrial transcriptome better than E2 alone.

Novel role for conceptus signals in mRNA expression regulation by DNA methylation in porcine endometrium during early pregnancy

“…The effects of E 2 , PGE 2 , and an E 2 + PGE 2 treatment were studied using a previously described in vivo model [ 4 , 25 , 27 ]. Prepubertal crossbred gilts of 6 months of age and a similar genetic background (Pietrain × Duroc) after the second natural estrus following puberty were treated hormonally with 750 IU of Pregnant Mare Serum Gonadotrophin (PMSG; Folligon, Intervet, Boxmeer, The Netherlands) and 500 IU of human chorionic gonadotropin (hCG; Chorulon, Intervet) given 72 h later to induce estrus.…”

“…The effects of E 2 , PGE 2 , and E 2 acting simultaneously with PGE 2 on endometrial DNMT1, DNMT3A, and DNMT3B protein expression were studied by using Western blot as described earlier [ 25 ]. Equal amounts of nuclear protein extracts (40 μg) were dissolved in SDS gel-loading buffer (50 mM/L Tris–HCl, pH 6.8; 4% SDS, 20% glycerol, and 2% β-mercaptoethanol), then denatured at 95°C for 4 min, and separated on 4–20% stain-free polyacrylamide gels (Bio-Rad, Hercules, CA, USA).…”

“…Genes important for processes accompanying development of early pregnancy such as metabolism ( ADH1C ), cell cycle regulation ( PSAT1 ), cell proliferation ( RASFF1 and DMBT1 ), and tissue remodeling ( ADAMTS20 , BGN and WNT5A ) [ 4 , 25 , 26 , 35 ] have been selected for local methylation analyses. DNA methylation assays for selected sequences of ADH1C , BGN , PSAT1 , and RSSF1 genes were designed earlier [ 26 , 35 ].…”

“…Functional annotation clustering analyses linked these alterations to the processes important for pregnancy establishment (i.e., tissue remodeling, regulation of immune response, cell proliferation, differentiation, and migration). Interestingly, within the identified processes, we found those that are related to DNA methylation [ 4 , 25 ]. Moreover, studies on the epigenetic effect of exogenous estradiol administration revealed E 2 -induced subtle but consistent hypomethylation of DNA within the promoter region of cyclin-dependent kinase inhibitor 2D ( CDKN2D ) and in exon 1 of phosphoserine aminotransferase 1 ( PSAT1 ) not only in the porcine endometrium and corpora lutea (CL) but also in F1 preimplantation embryos at day 10 of development [ 26 ].…”

The Top 100 Most Cited Articles on Intrauterine Adhesion: a Bibliometric Analysis

“…In order to reduce the recurrence rate of IUA and improve reproductive prognosis, the application of other preventative and treatment measures for comprehensive management of adhesions after the surgery is recommended [16][17][18]. These measures mainly include devices to keep opposing endometrial surfaces separated, such as intrauterine device (IUD) [19]; Foley catheter balloon [20]; auto-crosslinked hyaluronic acid (ACP) gel [21][22][23][24]; and interventions to promote endometrial regeneration, such estrogen [25,26], stem cell [27][28][29], stem cell exosome [30], amniotic epithelial cells [31], granulocyte colony-stimulating factor [32], platelet-rich plasma [33], and aspirin [34]. However, the efficacy of these measures is still not ideal: the reformation rate is as high as 48% [35], the conception rate is about 44.3%, and the live birth rate is 37.8% [36].…”