Showing papers on "Decidual cells published in 2002"

Expression of vascular endothelial growth factor (VEGF) and its receptors in human endometrium throughout the menstrual cycle and in early pregnancy.

Abstract: Immunohistochemistry for vascular endothelial growth factor (VEGF) and its receptors, fms-like tyrosine kinase (flt-1) and kinase insert domain-containing region (KDR), was performed on human endometrium obtained from patients with normal menstrual cycles, patients given oestrogen and progesterone, and women in early pregnancy. Intense immunostaining of VEGF was observed in both glandular epithelial and stromal cells during the mid-secretory phase; the immunostaining intensity was increased by administration of oestrogen plus progesterone and strong immunostaining was observed in decidual cells of early pregnancy. In addition to the immunostaining in vascular endothelial cells, strong KDR immunostaining was observed in glandular epithelial cells and in decidualized stromal cells induced by administration of oestrogen plus progesterone, whereas flt-1 immunostaining was negligible. Strong immunostaining for flt-1 and KDR was found in both vascular endothelial cells and decidual cells in early pregnancy. Endometrial stromal cells isolated from proliferative phase endometrium were incubated with oestrogen (10(-8) mol l-1) and medroxyprogesterone acetate (MPA; 10(-6) mol l-1) for 18 days to study the regulation of VEGF, flt-1 and KDR in endometrial stromal cells by oestrogen and progesterone. Expression of VEGF and KDR mRNAs was increased significantly by oestrogen and MPA, accompanied by decidualization, whereas flt-1 mRNA expression was not affected. In conclusion, VEGF and its receptors may play important roles in implantation and maintenance of pregnancy.

Pivotal role of CEACAM1 protein in the inhibition of activated decidual lymphocyte functions

Abstract: Lymphocytes in direct contact with embryonic extravillous trophoblasts constitute more than 40% of decidual cells and appear to play major roles in implantation and early gestation. A unique subset of NK cells, making up 70–80% of decidual lymphocytes, express high levels of CD56 but lack CD16. We have recently demonstrated a novel class I MHC–independent inhibitory mechanism of NK cell cytotoxicity that is mediated by CEACAM1 homotypic interactions. This mechanism is used by some melanoma cells to avoid attack, mainly by CD16– NK cells. We now demonstrate that CEACAM1 is expressed on primary extravillous trophoblasts and is upregulated on the vast majority of IL-2–activated decidual lymphocytes, including NK, T, and NKT cells. Importantly, we present evidence that CEACAM1 interactions inhibit the lysis, proliferation, and cytokine secretion of activated decidual NK, T, and NKT cells, respectively. In vivo analysis of decidual lymphocytes isolated from cytomegalovirus-infected (CMV-infected) pregnant women revealed a dramatic increase in the expression of CEACAM1. Finally, we suggest that a novel ligand for this adhesion molecule is present on the surface of CMV-infected fibroblasts. These combined results demonstrate a major role for the CEACAM1 protein in controlling local decidual immune responses.

Interleukin 11 advances progesterone-induced decidualization of human endometrial stromal cells.

Abstract: Differentiation of endometrial stromal cells into decidual cells is crucial for embryo implantation and placentation. Interleukin (IL)-11 signalling is essential for adequate decidualization in the mouse uterus. We examined the role of IL-11 during progesterone-induced decidualization of human endometrial stromal cells over a 10-12 day period, using prolactin (PRL) production as a decidual marker. These cells produced biologically active IL-11 and expressed IL-11, IL-11Ralpha and PRL mRNA during decidualization. Neutralization of endogenous IL-11 with an anti-human (hu)IL-11 antibody (AB) reduced production of PRL from day 8 and insulin-like growth factor binding protein (IGFBP)-1, another marker of decidualization, from day 10 of culture. Following AB washout, PRL and IGFBP-1 secretion increased. Addition of recombinant (r)huIL-11 (10 or 100 ng/ml) to endometrial stromal cells increased secretion of PRL from day 4 and IGFBP-1 from day 6 compared with progesterone alone. Morphological signs of differentiation accompanied biochemical differentiation in the progesterone-treated cells and were further induced by exogenous rhuIL-11. Our observations demonstrate that human endometrial stromal cells produce biologically active IL-11, which promotes progesterone-induced decidualization. These results suggest that IL-11 has both paracrine and autocrine actions on human endometrial stromal cells and plays an important role in preparing the human endometrium for implantation.

Activin A promotes human endometrial stromal cell decidualization in vitro.

Abstract: Decidualization of the endometrium is critical for implantation and placental development. Stromal cells differentiate causing widespread tissue remodeling. The mechanisms involved are unknown, although a number of known paracrine factors play contributory roles. From its known actions on cell differentiation and remodeling, we hypothesized that activin A regulates decidualization. Stromal cells produce activinβ A subunits with the onset of decidualization, and these cells coexpress activin receptors. Utilizing an in vitro model of stromal cell decidualization, we demonstrate that high concentrations of dimeric activin A are produced by decidual cells. Addition of activin A to cells undergoing decidualization resulted in a dose-dependent increase in PRL production, an established marker of decidualization. This response was inhibited by co-treatment with follistatin. Neutralization of endogenous activins significantly reduced the decidual response. This is the first report of dimeric activin A production ...

A dynamic shift of VEGF isoforms with a transient and selective progesterone-induced expression of VEGF189 regulates angiogenesis and vascular permeability in human uterus

Abstract: A key mechanism underlying physiological angiogenesis of the human endometrium is its ability to regenerate the vascular capillary network and to perform vascular remodeling (i.e., development of spiral arteries). Vascular endothelial growth factor (VEGF) is associated with angiogenesis and capillary permeability in this tissue. VEGF is expressed as several spliced variants, its main human isoforms contain 121 and 165 aa; 17β-estradiol (E2) increases endometrial VEGF, possibly in all isoforms. Here we show that progesterone (P) selectively increases the expression of the VEGF189 (V189) isoform in the human uterus. V189 is identified in the conditioned medium of stromal cells treated with E2 + P; its presence in this in vitro model of decidual stromal cells is detected after 6–8 days, using ELISA, and after 8–10 days, using Western blot analysis with different antibodies, including one specific for V189. The secretion pattern of V189 parallels that of the decidual protein IGFBP-1. V189 is secreted as a native isoform, as compared with the migration of recombinant V189 by SDS/PAGE. In situ hybridization and immunocytochemistry, performed on the same biopsies, suggest that decidual cells express V189 during the mid-late secretory phase of the menstrual cycle and early gestation. Finally, using an in vivo permeability assay, we show that native V189 increases capillary permeability. These observations demonstrate that P regulates V189 expression in decidual cells, which could have important implications for understanding uterine vascular remodeling and implantation, and may be relevant in a range of disease states such as edema and irregular bleeding.

Thrombin-enhanced matrix metalloproteinase-1 expression: a mechanism linking placental abruption with premature rupture of the membranes

Abstract: Objective: Given the strong clinical association between the decidual hemorrhage of placental abruption and subsequent preterm premature rupture of the membranes, we assessed the effects of thrombin on the expression of the potent interstitial collagenase, matrix metalloproteinase-1 (MMP-1), in cultured endometrial stromal and decidual cells. Study design: Stromal cells derived from predecidualized cycling endometrium and decidual cells from term decidua were cultured in a defined medium containing estradiol, to mimic the hormonal milieu of the non-pregnant proliferative phase, or estradiol plus medroxyprogesterone acetate (MPA), to mimic the hormonal milieu of pregnancy, in the presence and absence of thrombin. Culture media were examined for MMP-1 protein levels and cell lysates were examined for steady-state MMP-1 mRNA levels. Results: MPA strongly inhibited MMP-1 levels in endometrial stromal and term decidual cells. However, thrombin overcame this suppression, producing MMP-1 levels that were several...

Differential expression of microsomal prostaglandin E synthase at implantation sites and in decidual cells of mouse uterus

Abstract: Prostaglandin E 2 (PGE 2) is considered important for blastocyst spacing, implantation, and decidualization in the rodent uterus. PGE synthase (PGES) catalyzes the isomerization of PGH2 to PGE 2. There are two isoforms of PGES, microsomal PGES (mPGES) and cytosolic PGES (cPGES). However, the expression and regulation of mPGES in the mammalian uterus during early pregnancy are still unknown. The aim of this study was to investigate the differential expression of mPGES in mouse uterus during early pregnancy and its regulation under different conditions by in situ hybridization and immunohistochemistry. Microsomal PGES expression in the preimplantation mouse embryos was also performed by reverse transcription polymerase chain reaction (RT-PCR). Expression of mPGES mRNA and protein was at a basal level in the luminal epithelium from Day 1 to Day 4 of pregnancy. However, mPGES mRNA and protein were highly expressed in the stroma immediately surrounding the blastocyst but not in the luminal epithelium on Day 5 of pregnancy. Microsomal PGES mRNA and protein were not detected in the pseudopregnant uterus from Day 1 to Day 5. During delayed implantation, mPGES mRNA and protein were also not detected in the uterus. Once delayed implantation was terminated by estrogen treatment and embryo implantation initiated, both mPGES mRNA and protein were induced to express in the stroma immediately surrounding the blastocyst, which was similar to the expression pattern on Day 5 of pregnancy. From Day 6 to Day 8 of pregnancy, the signals for mPGES mRNA and protein were strongly detected in the decidualized cells. Microsomal PGES mRNA and protein were also highly expressed in the artificially decidualized cells but not in the control horn. Microsomal PGES mRNA was detected in the oocytes and all the stages of preimplantation embryos. The strong mPGES expression in the implantation site and decidual cells suggests that mPGES might play an important role during implantation and more importantly in decidualization. decidua, early development, female reproductive tract, implantation, uterus

Uterine Sensitization-Associated Gene-1: A Novel Gene Induced Within the Rat Endometrium at the Time of Uterine Receptivity/Sensitization for the Decidual Cell Reaction

Abstract: For successful implantation, the embryo must develop to the blastocyst stage and the endometrium must attain a state that is receptive to the implanting blastocyst. In rodents, the timing, duration, and hormonal regulation of this receptive state has been well defined. However, the molecular cascade of events involved in the onset of the receptive phase remains unclear. In the present study, we sought to identify genes involved in the onset of the receptivity using the technique of suppressive subtraction hybridization. Herein we report the isolation, cloning, and characterization of a novel gene, uterine sensitization-associated gene-1 (UASG-1), that is preferentially expressed within the maximally sensitized/receptive rat endometrium. USAG-1 mRNA encodes a putative protein of 206 amino acids that contains a possible N-terminal secretion signal and a C-terminal cystine knotlike motif. Northern blot analysis revealed that induction of USAG-1 mRNA was restricted to the Day 5 pregnant or pseudopregnant uterus. In situ hybridization experiments demonstrated that this induction was restricted to the uterine glandular epithelial cells. Given the remarkably tight restriction of its expression, USAG-1 may be involved in the onset of endometrial receptivity for implantation/sensitization for the decidual cell reaction.

Expression of hypoxia-inducible factors in human endometrium and suppression of matrix metalloproteinases under hypoxic conditions do not support a major role for hypoxia in regulating tissue breakdown at menstruation

Abstract: BACKGROUND: Classical studies in monkeys suggested that menstruation results from vasoconstriction, hypoxia and necrosis. The heterodimeric hypoxia-inducible factor (HIF) complex is critical in oxygen homeostasis via increased stability of HIF-1α/2α monomers, and these act as markers of hypoxia. We hypothesized that focal hypoxia in perimenstrual endometrium results in locally increased matrix metalloproteinases (MMP), leading to tissue destruction. METHODS: HIF-1α, HIF-2α and HIF-1β were immunolocalized in cycling endometrium. Endometrial stromal cells were cultured under hypoxic and normoxic conditions and MMP measured by zymography and Western blots. RESULTS: HIF-1α and HIF-2α were detected in only some endometrial samples, and not confined to the perimenstrual tissue. Where present, they were primarily cytoplasmic, not nuclear. HIF-1β was localized in epithelium, leukocytes and some decidual cells. Cultured endometrial stromal cells responded to hypoxia with increased cellular HIF-1α and secreted vascular endothelial growth factor. ProMMP-1 and proMMP-3 production was reduced in response to hypoxia regardless of the steroidal milieu (no added steroids, estrogen or estrogen plus progesterone). Active MMP-2 and membrane type 1 MMP but not proMMP-2 or proMMP-9 production were also inhibited by hypoxia. CONCLUSIONS: These results do not support a role for hypoxia in the focally increased production and activation of MMP observed prior to and during menstruation.

Defective Production of Interleukin-11 by Decidua and Chorionic Villi in Human Anembryonic Pregnancy

Abstract: Previous study demonstrated that IL-11 receptor knockout female mice (IL-11R / ) were phenotypically normal but infertile due to defective decidualization. However, the role of IL-11 signaling in human reproduction remains unclear. This study examined the expression of IL-11, IL-11R, and signal transduction factor glycoprotein 130 in different phases of endometrium (six in proliferative phase and four in secretory phase), and the decidua and villi of normal pregnancy (NP; n 25) and anembryonic pregnancy (AP; n 25) in the first trimester (gestational week 7–9). RT-PCR showed IL-11, IL-11R, and glycoprotein 130 mRNA expression in all samples, except the absence of IL-11 signal in the unstimulated MRC-5 cell and the proliferative phase endometrium. Real-time quantitative PCR showed that the relative level of IL-11R mRNA was not significantly different among proliferative phase endometrium (relative level; mean SEM, 1.4 0.5), secretory phase endometrium (1.3 0.1), or decidua from NP or AP (1.7 0.3 and 1.9 0.4, respectively), but was significantly greater in chorionic villi either from NP or AP (7.6 1.3 and 10.6 1.9, respectively; both P 0.05). In situ hybridization localized IL-11R mRNA expression in proliferative phase endometrium (stroma only), secretory phase endometrium (stroma and gland), decidua (stroma and gland), and villi (trophoblast and stroma). The staining intensities were not distinctly different between different groups of samples or between different cell types in a sample. No difference in IL-11R expression was found between NP and AP when either decidua or chorionic villi was analyzed. IL-11 mRNA level was not detected in the proliferative phase (relative level, 0.0 0.0), was barely detectable in the secretory phase (0.03 0.02), and was significantly increased in decidua (1.7 0.2 and 0.1 0.1, respectively, for NP and AP) and chorionic villi (13.0 2.2 and 0.2 0.1). In addition, IL-11 mRNA level was higher in NP than in AP both in decidua (1.7 0.2 vs. 0.1 0.1; P 0.03) and in villi (13.0 2.2 vs. 0.2 0.1; P < 0.001). Immunohistochemistry study showed that IL-11 was nearly absent in endometrium in both phases, but clearly detectable in decidua and villi. Consistent with the results of quantitative PCR, the staining intensity was stronger in villi and decidua from NP than those from AP. The spatial and temporal changes in IL-11 and its receptor observed in this study suggest that IL-11 may be produced both by the embryo (predominantly) and the decidual cells and exerts its action on chorionic villi and decidua in an autocrine or paracrine manner. In the presence of a baseline level of IL-11R, IL-11 may subsequently regulate placentation and decidualization for the maintenance of a NP. The finding of decreased IL-11 expression in the absence of any change in IL-11R in AP suggests that defective expression of IL-11 but not IL-11R may account for certain cases of AP. (J Clin Endocrinol Metab 87: 2320 –2328, 2002)

Calcitonin gene-related peptide (CGRP) and CGRP receptor expression at the human implantation site.

Abstract: Calcitonin gene-related peptide (CGRP) is a 37-amino acid neuropeptide produced by tissue-specific alternative splicing of the primary transcript of the calcitonin gene. The objectives of this study were: 1) to determine the expression of CGRP and its receptor at the human implantation site, and 2) to examine the possible in vitro effect of this neuropeptide on two major partners of implantation, decidual cells and extravillous cytotrophoblasts. Immunohistological analysis of first-trimester placental chorionic villi showed CGRP in decidual cells and glandular cells, but not in extravillous trophoblast cells. CGRP expression was confirmed in cultured decidual cells by Southern blot analysis and immunocytochemistry and by RIA in culture medium. Transcripts of calcitonin receptor-like receptor were detected by Southern blot analysis of RT-PCR amplicons from both decidual and extravillous trophoblast cells, whereas transcripts for the receptor activity-modifying protein 1 were detected in decidual cells only. In vitro, CGRP stimulated cAMP production but not nitric oxide (NO) release by cultured decidual cells; in contrast CGRP increased NO release but not cAMP production in cultured extravillous trophoblasts. The presence of NO synthase (endothelial and inducible) was confirmed by immunodetection in extravillous trophoblasts, both in situ and in vitro. This study points to a paracrine and autocrine effect of CGRP on decidual and extravillous trophoblast cells, two major actors in implantation.

Hox proteins activate the IGFBP-1 promoter and suppress the function of hPR in human endometrial cells

Abstract: Previous studies have shown that progestin activates the transcription of IGFBP-1 (insulin-like growth factor binding protein-1) Four regions in the IGFBP-1 promotor have been identified to enhance the transcription Two of the regions, located at -73 to -65 bp and -319 to -311 bp formed identical DNA-protein complexes with the nuclear extracts of endometrial stromal/decidual cells To identify the binding protein(s) in endometrial cells that interact with these two regions, we have used the TGTCAATTA repeats (-319 to -11 bp of the IGFBP-1 promoter) to screen the human decidual cDNA library by yeast one-hybrid system We found that Hox A10, HoxA11, HoxB2, HoxB4, and HoxD11 interacted with the TGTCAATTA repeats in yeast cells Among these hox genes, the full-length coding region of HoxA10, HoxA11, and HoxB4 were used for functional analysis in three types of endometrial cells, undifferentiated endometrial stromal cells, decidual cells (differentiated stromal cells) and endometrial adenocarcinoma cell line

Embryo Transfer Experiments and Ovarian Transplantation Identify the Ovary as the Only Site in Which Nuclear Receptor Interacting Protein 1/RIP140 Action Is Crucial for Female Fertility

Abstract: Spatial and temporal regulation of gene expression by a number of different nuclear receptors is critical in female reproduction. In this study we investigated whether the nuclear receptor corepressor nuclear receptor interacting protein 1 (Nrip1)/RIP140, which is essential for ovulation, is also required for postovulatory events, leading to pregnancy and parturition. Expression analysis indicated that Nrip1 is present in the uterus in stromal and glandular epithelial cells, primary decidual cells, and subsequently in differentiating decidual cells at the anti-mesometrial side of the implantation site. It also indicated a temporal regulation of Nrip1 in the corpora lutea at different stages of pregnancy, with increased levels at midgestation at approximately d 9.5 postcoitum (pc). By performing both embryo and ovarian transfer experiments we demonstrate that, provided the block to ovulation is by-passed, Nrip1−/− mice are capable of establishing and maintaining pregnancies. However, although the majority ...

Differential expression of secreted frizzled-related protein 4 in decidual cells during pregnancy

Abstract: During pregnancy, the uterus shows marked morphological and physiological changes under the regulation of ovarian steroid. To elucidate the molecular cues of these changes, we tried to identify the transcripts differentially expressed in the pregnant rat uterus by using the suppression subtractive hybridization method. Seven independent clones were isolated and one of the up-regulated genes was secreted frizzled-related protein 4 (sFRP4). sFRP4 contains a Wnt-binding domain and belongs to the secreted frizzled protein family whose members are assumed to function as modulators of the Wnt signal. The expression level of sFRP4 mRNA reached a peak in the pregnant uterus on day 12, when uterine decidualization was almost complete in the rat. In situ hybridization histochemistry revealed that sFRP4 transcripts were observed in the decidual cells. In addition, proliferating cell nuclear antigen (PCNA)-positive cells were shown to be overlapped in decidua, suggesting that sFRP4 mRNA expression was accompanied by the late phase of decidual cell proliferation. Moreover, sFRP4 and estrogen receptor-alpha transcripts were co-localized. Furthermore, we analyzed the regulation of sFRP4 by estrogen using 17 beta-estradiol-treated ovariectomized rats. sFRP4 mRNA was detected in the uterus at 48 h after estrogen treatment, especially in endometrial stroma where PCNA-positive cells were also observed. The results in this study led us to the notion that sFRP4 mRNA may be up-regulated after estrogen treatment in the late phase of uterine cell proliferation.

Control and expression of cystatin C by mouse decidual cultures.

Abstract: During mouse embryo implantation, trophoblast invasion is controlled in part by a balance of trophoblast-derived proteinases and uterine decidual proteinase inhibitors. Our work has focused on cystatin C, the secreted inhibitor of cathepsins B and L. We have previously shown that cystatin C is synthesized by the uterine decidua and localized to the cells in close contact with the trophoblast during implantation in vivo. In the work reported here we have established that decidualizing cultures show a similar upregulation of cystatin C. Using Northern and Western blotting and immunolocalization techniques both cystatin C mRNA and secreted protein increased with the morphological differentiation of stromal or decidual capsule cultures. In an effort to understand the regulation of cystatin C expression, decidual cells were analyzed under various culture conditions. Cystatin C expression was upregulated by increased cell density and by the presence of serum in the media. The growth factors TGF-β1 and EGF were found to induce cystatin C to levels comparable to serum stimulation. Co-culture with ectoplacental cones (EPCs) likewise induced expression and resulted in the localization of cystatin at the decidua:trophoblast interface. This work shows that decidualizing cultures are a good system to study cystatin C expression and that the expression is controlled in part by TGF-β1 and EGF signaling. Mol. Reprod. Dev. 61: 155–163, 2002. © 2002 Wiley-Liss, Inc.

Progesterone and the control of uterine cell proliferation and differentiation.

Abstract: Progesterone is the only steroid hormone that is essential for the establishment and maintenance of pregnancy in all mammalian species that have been studied. Mice lacking the progesterone receptor (PR) by targeted mutagenesis exhibit abnormalities in all aspects of reproduction including sexual behavior, mammary gland development, ovulation, and implantation. Implantation in PR null mice fails, in part, because the uterine stromal cells cannot undergo differentiation (the decidual cell reaction). Uterine stromal cells do not divide without progesterone and proliferation is blocked by progesterone antibodies and PR antagonism. In spite of the preeminence of progesterone in female reproduction, its molecular mechanisms of action on target cell proliferation and differentiation are not well understood. Recent studies suggest that progesterone plays a direct role in regulating cell cycle transit by increasing the expression and activation of cell cycle regulatory complexes. Furthermore, this progesterone-dependent regulation of cell cycle transit may provide a unique window of opportunity for uterine stromal cells to exit the proliferative cycle, and if exposed to appropriate agents, enter into the differentiation pathway.

Expression of prolactin-releasing peptide and its receptor in the human decidua*

Abstract: Human decidua and decidualized endometrial cells produce prolactin (PRL). Several growth factors and cytokines have been shown to regulate decidual PRL release, but a specific PRL-releasing substance remains to be characterized. Prolactin-releasing peptide (PrRP) is a peptide isolated from the brain and distinguished by its potent and specific stimulation of PRL release by cultured pituitary cells. Here, we demonstrate that human decidua expresses immunoreactive PrRP as well as the mRNAs encoding PrRP and its receptor. First trimester deciduas were obtained from women undergoing elective termination of pregnancy. Tissue specimens were stained by immunohistochemistry using a rabbit anti-human PrRP-31 antibody, and PrRP was localized in both epithelial cells of the decidual glands and in stromal cells, with diffuse distribution and no special relation with the neighbourhood of blood vessels. In primary cultures of decidual stromal cells, PrRP and PrRP receptor gene expression were detected using RT–PCR, and the identity of the PCR products was further confirmed by restriction enzyme digestion. The effect of PrRP on decidual PRL release was also evaluated, and there was a significant increase in PRL production (135 4% of control levels, P < 0.05) after incubation of decidual stromal cells with synthetic PrRP. The expression of PrRP and PrRP receptor in human decidual cells and the ability of PrRP to induce PRL secretion by cultured decidual cells suggests that this peptide may be a novel local modulator of decidual PRL release.

Expression and subcellular distribution of the active form of c-Src tyrosine kinase in differentiating human endometrial stromal cells.

Abstract: Decidual growth factors and locally produced cytokines are thought to activate specific phosphorylation signalling pathway(s), thereby eliciting a variety of decidual functions We have previously reported the activation of c-Src tyrosine kinase during ovarian steroid-induced decidualization of cultured human endometrial stromal cells As chicken c-Src is known to be activated upon dephosphorylation of tyrosine 527 (Y527, corresponding to Y530 in human), we here employed a monoclonal antibody, clone 28, directed against the active form of human c-Src whose Y530 is dephosphorylated, and investigated whether c-Src became dephosphorylated at Y530 and thereby activated during decidualization We found that the active form of c-Src was up-regulated and demonstrated increased kinase activity during in-vitro decidualization Immunohistochemistry revealed that decidual cells in early pregnancy decidua were intensely stained with clone 28 when compared with the stromal cells in the non-pregnant endometrium Moreover, the active form of c-Src translocated from a perinuclear region to the cytoplasm upon decidualization Thus, the Y530 dephosphorylation, kinase activation, and subcellular translocation of c-Src may be intracellular signalling events associated with decidualization in vivo as well as in vitro

Ultrastructure of the early human feto-maternal interface co-cultured in vitro

Abstract: BACKGROUND: The study was designed to investigate the ultrastructural features of the early human feto-maternal interface when generated by in-vitro co-culture, and compare these with findings reported previously from human pregnancies. METHODS: Placental villi and decidua parietalis tissues from 8-12 week pregnancies were co-cultured in vitro over a 4-day period. The co-incubations were ended at 24 h intervals and processed for electron microscopical studies, and for immunocytochemistry using anti-cytokeratin antibody (CAM 5.2) for trophoblast. RESULTS: Loss of the syncytium at points of contact with the decidual stroma, cytotrophoblast column formation, differentiation and invasion of extravillous trophoblast (EVT) cells into the decidual stroma over the 4-day period of co-culture were observed. Cellular components, such as actin filaments, microtubules, glycogen granules and lamellipodic processes found in EVT cells were consistent with active cellular locomotion. CONCLUSIONS: These ultrastructural studies emphasize the usefulness of this model in investigating the formation of the feto-maternal interface of human pregnancy. The recruitment of cytotrophoblast to the syncytium by a process involving fusion of the intervening plasma membranes, and the migration of EVT cells causing little or no damage to the surrounding decidual cells, resemble in-vivo data.

Premenstrual disappearance of aminopeptidase A in endometrial stromal cells around endometrial spiral arteries/arterioles during the decidual change.

Abstract: Aminopeptidase A (APA, BP-1) is a membrane-bound zinc metallopeptidase that converts angiotensin II (AngII) into AngIII by selectively hydrolyzing the N-terminal aspartyl residue. AngII has been proposed as a candidate for the initial vasoconstrictor of endometrial spiral arteries/arterioles in the preliminary step of menstruation. In the late secretory phase, endometrial stromal cells (ESC) around the blood vessels begin to differentiate into decidual cells, and AngII has been reported to accumulate around such vessels. However, whether there is a concurrent increase in renin or angiotensin-converting enzyme in this area has not been determined. We hypothesized that APA may be involved in the metabolism of AngII in the cycling endometrium. Western blot analysis in the present study demonstrated that a considerable amount of APA was present in the secretory phase endometrium. ESC in the secretory phase showed strong expression of APA by immunohistochemical analysis and of APA mRNA by in situ hybridization...

Protein kinase C stimulates release of matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 by human decidual cells.

Abstract: Objective: Increased concentrations of amniotic fluid matrix metalloproteinase (MMP)-9 and tissue inhibitor of metalloproteinase (TIMP)-1 have been observed in the context of premature rupture of membranes (PROM) and microbial invasion of the amniotic cavity. However, the source of the stimuli that contribute to the accumulation of these proteins in amniotic fluid remains to be identified. The present study was conducted to investigate MMP-2, MMP-9 and TIMP-1 secretion by decidual cells in response to activated protein kinase C (PKC). Methods: Decidual cells were isolated from term placentae, grown to confluence and incubated with control media or 10-11 to 10-8 mol/l concentrations of phorbol 12-myristate 13-acetate (PMA). Concentrations of MMP-2, MMP-9 and TIMP-1 in the culture supernatant were determined using sensitive and specific immunoassays. Substrate zymography was conducted to confirm MMP-9 assays. Results: PMA induced a concentration-dependent stimulation of release of MMP-9 (control vs. PMA 10-...

Stress neuropeptides in the human endometrium: paracrine effects on cell differentiation and apoptosis.

Abstract: Human endometrium exhibits characteristics of a neuroendocrine-like stress organ in addition to its classical role as the main target of ovarian steroid hormones. Indeed, the epithelial cells of human endometrium express the stress-associated neuropeptide genes corticotropin-releasing hormone (CRH), proopiomelanocortin, proenkephalin and prodynorphin. Furthermore, endometrium stroma cells also express CRH when they differentiate into decidual cells. Multiple lines of evidence suggest that the stress-associated neuropeptides of human endometrium are under the endocrine control of gonadal steroids as well as under an autocrine/paracrine regulation by prostanoids and interleukins. Endometrial stress-associated neuropeptides appear to exert their biological effect locally, i.e. within the uterus since human endometrium and myometrium also express the relevant receptors. More specifically, recent data suggest that endometrial CRH participates in the regulation of intrauterine inflammatory processes taking place in early pregnancy including stroma decidualization, blastocyst implantation and early maternal tolerance. Similarly, endometrial opioids participate in the regulation of uterine tissue remodeling via their effect on endometrial cell apoptosis. Thus, endometrial stress neuropeptides act as paracrine regulators of uterine cell differentiation and tissue remodeling as well as modulators of local immune responses.

Subtilisin proprotein convertase-6 expression in the mouse uterus during implantation and artificially induced decidualization.

Abstract: During implantation, a balance of factors regulates the invasive properties of the embryo and the anti-invasive properties of uterine decidua. Although antiproteinases such as the metalloproteinase inhibitor TIMP-3 are thought to play critical roles in preventing the overaggressive invasion of trophoblasts, the mechanism of antiproteinase regulation is unknown. Recently, the prohormone convertase SPC-6 has been found to be co-expressed in embryo-proximal decidua in association with TIMP-3. As members of this serine proteinase family are known to activate latent TGFβ family members which regulate decidual TIMP-3 levels, we sought to characterize the expression of SPC-6 during pregnancy and artificial decidualization. In this study, we demonstrate that the zone of SPC-6 gene expression exhibits a great degree of temporal and spatial overlap with TIMP-3 gene expression in uterine decidua from E5.5 through to E8.5. Like TIMP-3, we demonstrate that SPC-6 expression is induced during the decidual cell response using an in vivo model of artificial decidualization. Both the secreted and membrane bound forms of SPC-6 are expressed throughout the period of decidualization, suggesting that SPC-6 may play multiple roles during this developmental period. This is confirmed by our observation of the movement of SPC-6 expression to the presumptive placental region, as TIMP-3 expression regresses at the implantation site. Mol. Reprod. Dev. 61:453–459, 2002. © 2002 Wiley-Liss, Inc.

The characteristics of integrins expression in decidualized human endometrial stromal cell induced by 8-Br-cAMP in in vitro.

Abstract: Integrins are heterodimeric glycoproteins that have been found to undergo dynamic temporal and spatial changes in the endometrium during the menstrual cycle and in early pregnancy Specificity of integrins is known to be different in human endometrial stromal cells and decidual cells These shifts of integrins suggested to play an important role in embryo implantation and can be modulated by progesterone, cAMP derivatives, and cytokines The mechanisms of decidualization and its precise physiological role are still not clearly understood and in vitro systems could provide an alternative that overcomes limitations of studying such complex biological phenomena in vivo at the time of implantation This study was undertaken to establish an in vitro model system for human decidualization using 8-bromo-cAMP and to investigate the characteristics of stromal integrin expression in vitro by 8-Br-cAMP Endometrial stromal cells were isolated and cultured, and then were induced to decidualize by 05 mM 8-Br-cAMP for 15 days Immunofluorescence staining and flow cytometric analyses of the integrin subunits (α1, α4, α5, α6, β1 and αvβ3) were performed at day 9 In the presence of 8-Br-cAMP, the staining intensity of αvβ3 was significantly higher than control and measurements for α1, α4, α5, α6, and β1 were similar Immunofluorescent localization of the integrins reflected the differences obtained from the flow cytometric analyses described above In summary, the expression of αvβ3 integrin increased in stromal cells in vitro decidualized by 8-Br-cAMP and this up-regulation of αvβ3 integrin expression during decidualization might influence on human implantation

Immunolocalization of glucose transporter 1 and 3 in the placenta: application to cytodiagnosis of Papanicolaou smear.

Abstract: A positive immunostaining for glucose transporter 1 (GLUT1) was exclusively localized in microvilli on the free surface of syncytiotrophoblasts in the placenta. An enhanced immunoreaction for glucose transporter 3 (GLUT3) was elicited in the cell membrane of intermediate trophoblasts and cytotrophoblasts. Neither GLUT1 nor GLUT3 was positive in decidual cells and epithelial components from cervical dysplasia and carcinoma in situ. Cervicovaginal smears from six pregnant women containing atypical cells of unknown origin were subjected to immunocytochemical testing with antibodies against GLUT1 and GLUT3. Atypical cells in smears from two pregnant women were found to be positive for GLUT3 while no specific immunoreaction for GLUT1 was elicited, indicating their origin from either intermediate trophoblasts or cytotrophoblasts. Through the use of antibodies against vimentin and cytokeratin 17, GLUT3-negative atypical cells were further sorted into decidual cells and epithelial components from cervical dysplasia, respectively. Diagn. Cytopathol. 2002;26:373–379. © 2002 Wiley-Liss, Inc.

Apoptosis and expression of relative genes in early pregnant chorionic villi and decidua

Abstract: OBJECTIVE To investigate the effects of mifepristone on apoptosis and expression of relative genes in early pregnant chorionic villi and decidua. METHODS The specimen of early pregnant chorionic villi and decidua obtained from 10 cases of requesting termination of pregnancy by curettage, 20 cases of mifepriston contragestation. The paraffin sections were used to determine apoptotic cells by TdT-mediated dUTP-biotin nick end labeling method, to identify bcl-2, bax, fas, fasL and proliferating cell nuclear antigen (PCNA) by immunohistochemistry, to demonstrate fas and fasL mRNA by in situ hybridization. RESULTS In normal early pregnant specimens, apoptotic cells were mainly observed in syncytiotrophoblast, but not in cytotrophoblast cells, occasionally seen in decidua cells. The antigen of bax, fas, fasL were present in syncytiotrophoblast cells and decidua with lower amount. While bcl-2 antigen staining was strong in cytotrophoblastic cells and in decidua. PCNA protein was present in cytotrophoblastic and decidual cells only. In the specimens treated with mifepristone, apoptotic cells were increased in syncytiotrophoblastic cells of villi and visualized in decidua cells. The expression of fas, fasL and bax was also higher than that of normal. CONCLUSIONS Mifepristone increased apoptosis in syncytiotrophoblastic and decidua cells, but had no effect on the expression of bcl-2 and PCNA.

Expression of Survivin in Early Villus and Decidua and Its Implication

Abstract: Summary: To investigate the expression and implication of survivin protein and mRNA in decidua and villus and the effects of mifepristone on its expression, survivin levels in decidua and villus collect-ed from 15 normal early pregnant women and 15 early pregnant women pretreated with 150 mg mifepristone and 400 μg misoprostol were assessed by immuno-histochemical techniques and reverse transcriptional-polymerase chain reaction (RT-PCR). Our results showed that survivin proteins were stained in the cytoplasm of trophoblasts and decidual cells and in the nuclei of some of the decidual glandular epithelial cells. The expression was strongest in the trophoblasts and decidual glandular ep-ithelial cells. The expression values in the villus and decidua were (14.56 ± 2.44) and (10. 46 ± 2.81 ) respectively for normal pregnant and (8. 45 ± 2.08), (7.33 ± 1.91) for those pretreated with mifepristone respectively (P＜0. 05). The transcription of survivin mRNA in villus and decidua of those pretreated with mifepristone decreased significantly compared with those in the normal pregnant women (P＜0. 05). It is concluded that survivin can be expressed in the decidua and villus and mifepristone inhibits its mRNA transcription and protein expression, which could possibly be one of the factors inducing decidual and villous apoptosis.