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1.
Mol Cell Endocrinol ; 358(2): 166-75, 2012 Jul 25.
Article in English | MEDLINE | ID: mdl-21745536

ABSTRACT

Androgens and the androgen receptor (AR) are not only required for male reproductive function, they are also essential for female reproductive physiology. Widely expressed in female reproductive tissues, AR levels fluctuate in a regulated manner in the cycling endometrium. Female androgen production depends on the adrenal glands and expression of key enzymes in the endometrium that facilitate local androgen biosynthesis and conversion. Moreover, levels of circulating androgens, in women of reproductive age, fluctuate in a cycle-dependent manner and a mid-cycle peak is associated with conception. AR and androgen signalling have a decisive role in the differentiation of human endometrial stromal cells into decidual cells. Compelling evidence for androgen signalling in the regulation of endometrial function pertaining to implantation and pregnancy is provided by epidemiological studies demonstrating a strong association between polycystic ovary syndrome, premature ovarian failure or advanced maternal age and adverse pregnancy outcome. Thus, androgen signalling is an essential component of normal endometrial physiology and its perturbation is associated with reproductive failure.


Subject(s)
Androgens/metabolism , Endometrium/metabolism , Menstrual Cycle/physiology , Receptors, Androgen/metabolism , Animals , Female , Humans , Reproduction , Signal Transduction
2.
Endocrinology ; 151(8): 3954-64, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20519371

ABSTRACT

The androgen receptor (AR) is a ligand-dependent transcription factor, expressed in male and female reproductive organs, and essential for normal reproduction in both sexes. The levels of AR are tightly controlled in androgen-responsive cells in which it plays a central role in the regulation of target gene expression. The AR is abundantly expressed in human endometrial stromal cells (HESCs), but levels decline markedly after differentiation into decidual cells in vivo and in primary cultures. Decidualization profoundly down-regulated AR protein levels with no discernible effect on either AR mRNA or protein stability, suggesting that loss of the receptor was a consequence of translational inhibition. Here we show that HESCs express three RNA-binding proteins, Hu antigen R and the poly(C)-binding proteins PCBP1 and PCBP2, that reportedly target the 3'-untranslated region of AR transcripts. Only PCBP1 expression was enhanced in secretory endometrium in vivo and in decidualizing HESCs. Furthermore, knockdown of PCBP1 in decidualizing cells was sufficient to restore AR protein levels, indicating that loss of the AR protein is primarily the consequence of a translational block. PCBP1 also blocked AR translation in a cell-free system, although this did not require binding to the 3'-untranslated region of the receptor mRNA. Furthermore, knockdown of PCBP1 in the prostate cancer LNCaP cell line also increased AR protein. Therefore, PCBP1 plays a major role in the dynamic expression of AR in both male and female androgen-responsive cells.


Subject(s)
Heterogeneous-Nuclear Ribonucleoproteins/physiology , Receptors, Androgen/genetics , Adolescent , Adult , Androgen Receptor Antagonists , Cell Differentiation/genetics , Cells, Cultured , DEAD-box RNA Helicases/antagonists & inhibitors , DEAD-box RNA Helicases/genetics , DNA-Binding Proteins , Endometrium/metabolism , Endometrium/physiology , Female , Gene Expression Regulation , Gene Knockdown Techniques , Heterogeneous-Nuclear Ribonucleoproteins/genetics , Heterogeneous-Nuclear Ribonucleoproteins/metabolism , Humans , Male , RNA, Small Interfering/pharmacology , RNA-Binding Proteins , Receptors, Androgen/metabolism , Ribonuclease III/antagonists & inhibitors , Ribonuclease III/genetics , Stromal Cells/metabolism , Stromal Cells/physiology , Young Adult
3.
Fertil Steril ; 91(3): 937-9, 2009 Mar.
Article in English | MEDLINE | ID: mdl-18279855

ABSTRACT

This pilot study investigates in a group of 20 healthy volunteers with regular cycles and prior experience in natural family planning methods whether self-assessment of the cervical "pupil sign" is feasible and can be used to detect the preovulatory fertile window. All participants were able to assess the cervical pupil sign. Based on this method, the fertile window lasts on average 3 days, which is significantly shorter and more consistent than when defined on basis of the vulvar mucus method.


Subject(s)
Awareness , Cervix Uteri/anatomy & histology , Fertility , Menstrual Cycle , Natural Family Planning Methods , Ovulation Detection , Self Care , Adult , Feasibility Studies , Female , Health Knowledge, Attitudes, Practice , Humans , Mucus/metabolism , Natural Family Planning Methods/instrumentation , Ovulation Detection/instrumentation , Patient Education as Topic , Pilot Projects , Self Care/instrumentation , Surgical Instruments , Time Factors , Vulva/metabolism , Young Adult
4.
Endocrinology ; 149(9): 4462-74, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18511503

ABSTRACT

Progesterone is indispensable for differentiation of human endometrial stromal cells (HESCs) into decidual cells, a process that critically controls embryo implantation. We now show an important role for androgen receptor (AR) signaling in this differentiation process. Decreased posttranslational modification of the AR by small ubiquitin-like modifier (SUMO)-1 in decidualizing cells accounted for increased responsiveness to androgen. By combining small interfering RNA technology with genome-wide expression profiling, we found that AR and progesterone receptor (PR) regulate the expression of distinct decidual gene networks. Ingenuity pathway analysis implicated a preponderance of AR-induced genes in cytoskeletal organization and cell motility, whereas analysis of AR-repressed genes suggested involvement in cell cycle regulation. Functionally, AR depletion prevented differentiation-dependent stress fiber formation and promoted motility and proliferation of decidualizing cells. In comparison, PR depletion perturbed the expression of many more genes, underscoring the importance of this nuclear receptor in diverse cellular functions. However, several PR-dependent genes encode for signaling intermediates, and knockdown of PR, but not AR, compromised activation of WNT/beta-catenin, TGFbeta/SMAD, and signal transducer and activator of transcription (STAT) pathways in decidualizing cells. Thus, the nonredundant function of the AR in decidualizing HESCs, centered on cytoskeletal organization and cell cycle regulation, implies an important role for androgens in modulating fetal-maternal interactions. Moreover, we show that PR regulates HESC differentiation, at least in part, by reprogramming growth factor and cytokine signal transduction.


Subject(s)
Decidua/physiology , Endometrium/physiology , Gene Expression Regulation , Gene Regulatory Networks , Receptors, Androgen/physiology , Receptors, Progesterone/physiology , Cells, Cultured , Decidua/metabolism , Endometrium/metabolism , Female , Gene Expression Profiling , Humans , Oligonucleotide Array Sequence Analysis , Protein Processing, Post-Translational , Receptors, Androgen/metabolism , SUMO-1 Protein/metabolism
5.
Mol Endocrinol ; 21(10): 2334-49, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17609436

ABSTRACT

Differentiation of human endometrial stromal cells (HESCs) into decidual cells is associated with induction of the forkhead transcription factor forkhead box O1A (FOXO1). We performed a genomic screen to identify decidua-specific genes under FOXO1 control. Primary HESCs were transfected with small interfering RNA targeting FOXO1 or with nontargeting control small interfering RNA before treatment with a cAMP analogue and the progestin, medroxyprogesterone acetate for 72 h. Total RNA was processed for whole genome analysis using high-density oligonucleotide arrays. We identified 3405 significantly regulated genes upon decidualization of HESCs, 507 (15.3%) of which were aberrantly expressed upon FOXO1 knockdown. Among the most up-regulated FOXO1-dependent transcriptional targets were WNT signaling-related genes (WNT4, WNT16 ), the insulin receptor (INSR), differentiation markers (PRL, IGFBP1, and LEFTY2), and the cyclin-dependent kinase inhibitor p57(Kip2) (CDKN1C). Analysis of FOXO1-dependent down-regulated genes uncovered several factors involved in cell cycle regulation, including CCNB1, CCNB2, MCM5, CDC2 and NEK2. Cell viability assay and cell cycle analysis demonstrated that FOXO1 silencing promotes proliferation of differentiating HESCs. Using a glutathione-S-transferase pull-down assay, we confirmed that FOXO1 interacts with progesterone receptor, irrespectively of the presence of ligand. In agreement, knockdown of PR disrupted the regulation of FOXO1 target genes involved in differentiation (IGFBP1, PRL, and WNT4) and cell cycle regulation (CDKN1, CCNB2 and CDC2) in HESCs treated with either cAMP plus medroxyprogesterone acetate or with cAMP alone. Together, the data demonstrate that FOXO1 engages in transcriptional cross talk with progesterone receptor to coordinate cell cycle regulation and differentiation of HESCs.


Subject(s)
Cell Differentiation/genetics , Endometrium/metabolism , Forkhead Transcription Factors/metabolism , Gene Expression Regulation, Developmental , Receptors, Progesterone/metabolism , Cell Cycle/genetics , Cells, Cultured , Endometrium/cytology , Female , Forkhead Box Protein O1 , Humans , Oligonucleotide Array Sequence Analysis , Stromal Cells/metabolism , Transcription, Genetic
6.
Arch Gynecol Obstet ; 275(6): 475-9, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17514374

ABSTRACT

INTRODUCTION: The aim of the study is to determine whether a dedicated ectopic pregnancy team improves the management of haemodynamically stable patients with suspected ectopic pregnancy who do not require immediate life-saving surgery. METHODS: A non-randomized population based study involving 210 patients admitted with a suspected ectopic pregnancy over a 2-year period in a university teaching hospital in the UK, was carried out to compare the management of those women before and after the introduction of the ectopic pregnancy team. RESULTS: Following the introduction of an ectopic pregnancy team, there were fewer laparotomies performed, fewer negative diagnostic laparoscopies, a reduced overall surgical intervention rate, and a reduced duration of hospital stay. Although, it was difficult to quantify the extent of improvement of training, yet there were fewer operations performed out-of-hours, more continuity of care, more learning opportunities and acquisition of laparoscopic skills of junior staff. CONCLUSIONS: The introduction of an ectopic pregnancy team led to an improvement in the management of patients with suspected ectopic pregnancies. Efforts aiming at setting up such a specialized team and its implementation in day-to-day clinical practice should be considered in hospitals where the mainstay of treatment remains laparotomy.


Subject(s)
Delivery of Health Care , Pregnancy, Ectopic/diagnosis , Adult , Female , Humans , London , Patient Care Team , Pregnancy , Pregnancy, Ectopic/therapy , Prospective Studies , Retrospective Studies , Urban Population
7.
Hum Reprod ; 22(6): 1725-9, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17452394

ABSTRACT

BACKGROUND: We postulated that impaired endometrial differentiation in women with pelvic endometriosis predisposes for pre-eclampsia. METHODS: A retrospective case-control study set at the University of Ghent IVF centre. The incidence of pre-eclampsia and pregnancy-induced hypertension (PIH) following the clinical and/or laparoscopic diagnosis of endometriosis-associated infertility (case group; n = 245 pregnancies) was compared with the incidence of these obstetric complications in pregnancies following treatment for male-factor infertility (control group; n = 274 pregnancies). Pregnancy data were obtained by searching electronic databases and postal questionnaires. The case and control groups were matched for age, parity and multiple pregnancies. RESULTS: The incidence of pre-eclampsia was significantly lower in the case group (0.8%) when compared with control group (5.8%) (P = 0.002; odds ratio (OR) = 7.5, 95% confidence interval (CI): 1.7-33.3). Analysis of obstetric outcome in the subgroup of patients with laparoscopic data confirmed the lower risk of pre-eclampsia in the case (1.2%) versus control (7.4%) groups (P = 0.032; OR = 6.6, 95% CI: 1.2-37). PIH occurred in 3.5% and 8.7% of case and control pregnancies, respectively (P = 0.018; OR = 2.6, 95% CI: 1.2-6.0). The odds of developing pre-eclampsia were 5.67 times higher in the control group than in pregnancies following endometriosis-associated infertility. In multiple pregnancies, the odds of developing pre-eclampsia increased 1.93 times per additional child, with or without endometriosis. CONCLUSIONS: We found no evidence that endometriosis predisposes for pre-eclampsia. Instead, the risk of hypertensive disorder in pregnancy is significantly reduced in women with endometriosis-associated infertility.


Subject(s)
Endometriosis/complications , Pre-Eclampsia/epidemiology , Uterine Diseases/complications , Adult , Case-Control Studies , Female , Humans , Incidence , Middle Aged , Pregnancy , Risk
8.
Best Pract Res Clin Obstet Gynaecol ; 20(4): 479-91, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16631411

ABSTRACT

Magnetic resonance imaging has revealed that the endometrio-myometrial interface constitutes a distinct, hormone-dependent uterine compartment termed the junctional zone. In the non-pregnant uterus, highly specialized contraction waves originate exclusively from the junctional zone and participate in the regulation of diverse reproductive events, such as sperm transport, embryo implantation, and menstrual shedding. Conversely, growing evidence suggests that disruption of the normal endometrio-myometrial interface plays an integral role in diverse reproductive disorders. This chapter reviews our current understanding of the mechanisms that govern the cyclic changes in the uterine junctional zone and summarizes the evidence implicating the endometrio-myometrial interface in normal uterine physiology and pathological processes.


Subject(s)
Uterus/anatomy & histology , Uterus/physiology , Endometriosis/pathology , Endometriosis/physiopathology , Endometrium/anatomy & histology , Endometrium/physiology , Female , Humans , Myometrium/anatomy & histology , Myometrium/physiology , Pregnancy , Pregnancy Complications/pathology , Pregnancy Complications/physiopathology , Uterine Diseases/pathology , Uterine Diseases/physiopathology , Uterine Neoplasms/pathology , Uterine Neoplasms/physiopathology , Uterus/pathology
9.
Mol Hum Reprod ; 12(4): 237-43, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16556679

ABSTRACT

Heparin is used clinically for the prevention of pregnancy complications associated with prothrombotic disorders, especially antiphospholipid antibody syndrome. Recent studies have suggested that heparin may exert direct effects on placental trophoblast, independently of its anticoagulant activity. We now demonstrate that heparin abrogates apoptosis of primary first trimester villous trophoblast in response to treatment with the pro-inflammatory cytokines interferon (IFN)-gamma and tumour necrosis factor (TNF)-alpha. This multifunctional glycosaminoglycan also inhibited apoptosis induced by other agents, including staurosporin, broad-spectrum kinase inhibitor and thrombin. Furthermore, heparin attenuated caspase-3 activity, a hallmark of apoptosis, in human first trimester villous and extravillous trophoblast cell lines treated with peptidoglycan, a Toll-like receptor-2 agonist isolated from Staphylococcus aureus. The ability of heparin to antagonize cell death induced by such diverse apoptotic signals suggested that it acts as a survival factor for human trophoblast. We demonstrate that heparin, like epidermal growth factor (EGF) and heparin-binding EGF (HB-EGF), elicits phosphorylation of the EGF receptor and activation of the phosphatidyl inositol 3-kinase (PI3K)-, the extracellular signal-related kinase 1/2 (ERK1/2)- and the c-Jun NH2 terminal kinase (JNK)-signal transduction pathways in primary villous trophoblast. In summary, we have demonstrated that heparin activates multiple anti-apoptotic pathways in human trophoblast. Our results suggest that heparin may be useful in the management of at-risk patients, even in the absence of an identifiable thrombophilic disorder.


Subject(s)
Apoptosis/drug effects , Heparin/pharmacology , Caspase 3 , Caspases/metabolism , Cell Line , Cell Survival/drug effects , Cells, Cultured , Epidermal Growth Factor/metabolism , Female , Heparin-binding EGF-like Growth Factor , Humans , Intercellular Signaling Peptides and Proteins , JNK Mitogen-Activated Protein Kinases/metabolism , Mitogen-Activated Protein Kinase Kinases/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Pregnancy , Signal Transduction/drug effects , Signal Transduction/physiology , Trophoblasts/cytology , Trophoblasts/drug effects , Trophoblasts/enzymology , Tumor Necrosis Factor-alpha/metabolism
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