45 research outputs found
Endometrial stromal cells of women with recurrent miscarriage fail to discriminate between high- and low-quality human embryos
No full textBackground
The aetiology of recurrent miscarriage (RM) remains largely unexplained. Women with RM have a shorter time to pregnancy interval than normally fertile women, which may be due to more frequent implantation of non-viable embryos. We hypothesized that human endometrial stromal cells (H-EnSCs) of women with RM discriminate less effectively between high-and low-quality human embryos and migrate more readily towards trophoblast spheroids than H-EnSCs of normally fertile women.
Methodology/Principal Findings
Monolayers of decidualized H-EnSCs were generated from endometrial biopsies of 6 women with RM and 6 fertile controls. Cell-free migration zones were created and the effect of the presence of a high-quality (day 5 blastocyst, n = 13), a low-quality (day 5 blastocyst with three pronuclei or underdeveloped embryo, n = 12) or AC-1M88 trophoblast cell line spheroid on H-ESC migratory activity was analyzed after 18 hours. In the absence of a spheroid or embryo, migration of H-EnSCs from fertile or RM women was similar. In the presence of a low-quality embryo in the zone, the migration of H-EnSCs of control women was inhibited compared to the basal migration in the absence of an embryo (P<0.05) and compared to the migration in the presence of high-quality embryo (p<0.01). Interestingly, the migratory response H-EnSCs of women with RM did not differ between high- and low-quality embryos. Furthermore, in the presence of a spheroid their migration was enhanced compared to the H-EnSCs of controls (p<0.001).
Conclusions
H-EnSCs of fertile women discriminate between high- and low-quality embryos whereas H-EnSCs of women with RM fail to do so. H-EnSCs of RM women have a higher migratory response to trophoblast spheroids. Future studies will focus on the mechanisms by which low-quality embryos inhibit the migration of H-EnSCs and how this is deregulated in women with RM
Control of human endometrial stromal cell motility by PDGF-BB, HB-EGF and trophoblast-secreted factors
No full textHuman implantation involves extensive tissue remodeling at the fetal-maternal interface. It is becoming increasingly evident that not only trophoblast, but also decidualizing endometrial stromal cells are inherently motile and invasive, and likely contribute to the highly dynamic processes at the implantation site. The present study was undertaken to further characterize the mechanisms involved in the regulation of endometrial stromal cell motility and to identify trophoblast-derived factors that modulate migration. Among local growth factors known to be present at the time of implantation, heparin-binding epidermal growth factor-like growth factor (HB-EGF) triggered chemotaxis (directed locomotion), whereas platelet-derived growth factor (PDGF)-BB elicited both chemotaxis and chemokinesis (non-directed locomotion) of endometrial stromal cells. Supernatants of the trophoblast cell line AC-1M88 and of first trimester villous explant cultures stimulated chemotaxis but not chemokinesis. Proteome profiling for cytokines and angiogenesis factors revealed neither PDGF-BB nor HB-EGF in conditioned media from trophoblast cells or villous explants, while placental growth factor, vascular endothelial growth factor and PDGF-AA were identified as prominent secretory products. Among these, only PDGF-AA triggered endometrial stromal cell chemotaxis. Neutralization of PDGF-AA in trophoblast conditioned media, however, did not diminish chemoattractant activity, suggesting the presence of additional trophoblast-derived chemotactic factors. Pathway inhibitor studies revealed ERK1/2, PI3 kinase/Akt and p38 signaling as relevant for chemotactic motility, whereas chemokinesis depended primarily on PI3 kinase/Akt activation. Both chemotaxis and chemokinesis were stimulated upon inhibition of Rho-associated, coiled-coil containing protein kinase. The chemotactic response to trophoblast secretions was not blunted by inhibition of isolated signaling cascades, indicating activation of overlapping pathways in trophoblast-endometrial communication. In conclusion, trophoblast signals attract endometrial stromal cells, while PDGF-BB and HB-EGF, although not identified as trophoblast-derived, are local growth factors that may serve to fine-tune directed and non-directed migration at the implantation site
Motilität von humanen endometrialen Stromazellen : Rolle in der Implantation und Plazentation
No full textFür die erfolgreiche Implantation einer humanen Blastozyste und Ausbildung der Plazenta ist die tiefe Invasion der Trophoblastzellen in das Endometrium Grundvoraussetzung. Neuere Studien zeigen, dass dezidualisierte endometriale Stromazellen ebenfalls ein migratorisches Potential besitzen. Hierdurch könnte die Umstrukturierung des Gewebes und die Einnistung der Blastozyste aktiv unterstützt werden. In dieser Arbeit wurde die gerichtete (Chemotaxis) und die ungerichtete (Chemokinese) Migration nicht dezidualisierter und dezidualisierter humaner endometrialer Stromazellen verglichen. Faktoren, welche zum Zeitpunkt der Implantation lokal im uterinen Milieu nachgewiesen worden waren, sowie Trophoblast-Sekretionsprodukte wurden hinsichtlich ihres Einflusses auf die Migration untersucht. Zusätzlich sollten die beteiligten Signaltransduktionen aufgeschlüsselt werden.
Es zeigte sich, dass die Dezidualisierung das basale migratorische Potential endometrialer Stromazellen leicht erhöhte. Unter den Chemotaxis auslösenden Faktoren war einzig PDGF-BB in der Lage, auch eine chemokinetische Motilität der endometrialen Stromazellen zu induzieren. Die chemotaktische Antwort auf HB-EGF wurde durch Dezidualisierung der Zellen verstärkt, was mit einer erhöhten Expression seines Rezeptors EGFR korrelierte. Überstandsmedium sowohl von der Trophoblastzelllinie AC-1M88 als auch von primären Chorionzotten-Explantaten löste eine Chemotaxis aus. Anhand einer Proteom-Analyse wurde PDGF-AA als chemotaktisch aktive Komponente der Trophoblast-Überstände identifiziert, wohingegen die Sekretionsprodukte MIF, PLGF, TGF-β1 und VEGF unwirksam waren. PDGF-BB und HB-EGF wurden in den Trophoblast-Überstandsmedien nicht aufgefunden. Inhibitor-Studien zeigten, dass Signalkaskaden unter Beteiligung von PI3K/Akt(Ser473), ERK1/2 und p38 für die Chemotaxis relevant sind, während eine Chemokinese vorrangig von der Aktivierung des PI3K/Akt(Ser473)-Weges abhängig ist. Sowohl Chemotaxis als auch Chemokinese wurden durch Inhibierung der RhoA/ROCK-Signaltransduktion massiv stimuliert.
Zusammenfassend könnte folgendes Modell postuliert werden: Vom Trophoblasten ausgehende chemotaktische Signale, unter anderem PDGF-AA, veranlassen die sich in der Nähe des Invasionsortes befindlichen dezidualisierten Stromazellen, sich in Richtung des „Eindringlings“ zu bewegen. In der sich ausbildenden Dezidua führen von verschiedenen Zelltypen produzierte Faktoren, wie HB-EGF und PDGF-BB, zu einer Migration in Richtung lokaler Gradienten, und PDGF-BB stimuliert darüber hinaus die generelle ungerichtete Motilität der endometrialen Stromazellen. Insgesamt unterstützen diese Prozesse den für Implantation und Plazentation erforderlichen Gewebeumbau.Successful implantation of a human blastocyst and formation of the placenta requires deep invasion of the trophoblast into the decidualized endometrium. It is assumed that decidualized tissue forms a passive barrier that limits trophoblast invasion. Recently, it became evident that human endometrial stromal cells also have remarkable motile and invasive capacities, which may facilitate the extensive tissue remodelling associated with implantation and placentation.
In the present study, directed migration (chemotaxis) and random migration (chemokinesis) of non-decidualized and decidualized human endometrial stromal cells were characterized. Local factors, present in the uterine environment at the time of implantation, and trophoblast-derived factors were tested for their ability to modulate stromal cell motility. Further, involved signalling pathways were dissected.
A modest increase of basal motility was observed in human endometrial stromal cells upon decidualization. Among the factors inducing chemotactic migration, solely PDGF-BB also elicited a chemokinetic response. Chemotaxis towards HB-EGF was increased in decidualized human endometrial stromal cells compared to non-decidualized human endometrial stromal cells, coincident with up-regulation of the HB-EGF receptor EGFR. Chemotaxis of endometrial stromal cells was stimulated by supernatants prepared from the trophoblast cell line AC-1M88 and from first trimester villous explant cultures. Proteome profiling of trophoblast supernatants revealed PDGF-AA as a chemotactic component, whereas other prominent trophoblast secretions, including MIF, PLGF, TGF-β1 and VEGF, were ineffective. PDGF-BB and HB-EGF were not detectable as trophoblast secretory products.
By using specific pathway inhibitors, signalling through ERK1/2, PI3K/Akt(Ser473) and p38 were demonstrated to be involved in chemotaxis. Chemokinesis, on the other hand, appeared to depend mainly on activation of the PI3K/Akt(Ser473) pathway. Chemotaxis and chemokinesis were both massively stimulated by inhibition of the RhoA/ROCK signalling cascade.
In conclusion, we postulate the following scenario for early human pregnancy: Trophoblast-derived products, including PDGF-AA, induce a chemotactic response in decidualized endometrial stromal cells towards the implanting intruder. Within the developing decidua, various cell populations produce factors like HB-EGF and PDGF-BB, which trigger endometrial stromal cell migration in response to local gradients. PDGF-BB additionally stimulates random endometrial stromal cell motility. In concert, these processes contribute to tissue remodelling at the fetal-maternal interface
CCAAT/Enhancer-binding Proteins Are Mediators in the Protein Kinase A-dependent Activation of the Decidual Prolactin Promoter
No full textHoney, we need to talk about the membrane progestin receptors
No full textThe recent discovery of three closely related cell surface receptors that bind to progesterone and mediate its actions on various cytoplasmic signalling cascades has been heralded as a major break-through. The reason for this is all too obvious. Progesterone is an essential regulator of all major reproductive events and progestins and antiprogestins are widely used in the treatment of many different gynaecological and obstetrical disorders. The novel membrane progestin receptors (mPRα, β, γ) reportedly resemble and function as G-protein-coupled receptors and therefore are promising pharmaceutical targets. However, our studies failed to corroborate that mPRs are expressed on the cell surface, that they mediate rapid progesterone signalling events, and even that they are bona fide progestin binding moieties. While the reason for these startling opposing results remains unclear, a critical review of existing data may help to shed some light onto the controversial mPRs. Time has come to talk
HoxA-11 and FOXO1A Cooperate to Regulate Decidual Prolactin Expression: Towards Inferring the Core Transcriptional Regulators of Decidual Genes
No full textDuring the menstrual cycle, the ovarian steroid hormones estrogen and progesterone control a dramatic transcriptional reprogramming of endometrial stromal cells (ESCs) leading to a receptive state for blastocyst implantation and the establishment of pregnancy. A key marker gene of this decidualization process is the prolactin gene. Several transcriptional regulators have been identified that are essential for decidualization of ESCs, including the Hox genes HoxA-10 and HoxA-11, and the forkhead box gene FOXO1A. While previous studies have identified downstream target genes for HoxA-10 and FOXO1A, the role of HoxA-11 in decidualization has not been investigated. Here, we show that HoxA-11 is required for prolactin expression in decidualized ESC. While HoxA-11 alone is a repressor on the decidual prolactin promoter, it turns into an activator when combined with FOXO1A. Conversely, HoxA-10, which has been previously shown to associate with FOXO1A to upregulate decidual IGFBP-1 expression, is unable to upregulate PRL expression when co-expressed with FOXO1A. By co-immunoprecipitation and chromatin immunoprecipitation, we demonstrate physical association of HoxA-11 and FOXO1A, and binding of both factors to an enhancer region (−395 to −148 relative to the PRL transcriptional start site) of the decidual prolactin promoter. Because FOXO1A is induced upon decidualization, it serves to assemble a decidual-specific transcriptional complex including HoxA-11. These data highlight cooperativity between numerous transcription factors to upregulate PRL in differentiating ESC, and suggest that this core set of transcription factors physically and functionally interact to drive the expression of a gene battery upregulated in differentiated ESC. In addition, the functional non-equivalence of HoxA-11 and HoxA-10 with respect to PRL regulation suggests that these transcription factors regulate distinct sets of target genes during decidualization
