IL-11 and IL-11Ralpha immunolocalisation at primate implantation sites supports a role for IL-11 in placentation and fetal development

Comparison of serum levels of cell adhesion molecules (E-selectin, P-selectin, ICAM-1, VCAM-1, LRG-1) in placental invasion and adhesion anomalies with patients with vaginal delivery and former cesarean

OBJECTIVE

It is aimed to be a technique that can be used for diagnosis and to prevent maternal deaths in cases where the serum levels of cell adhesion molecules are different in patients with abnormal placentation compared to healthy pregnant women.

MATERIALS AND METHODS

Patients between March 2020 and September 2021 were included in the study. While 56 patients, out of 153 cases formed the placental adhesion and/or localization anomaly group, 55 cases without placental adhesion anomaly (placental invasion anomaly and/or previa pathology) constituted the cesarean section group and 42 cases constituted the vaginal birth control group. Demographic characteristics and histories of 153 patients were questioned. I-CAM-1, V-CAM-1, E-Selectin, P-Selectin, LRG-1 levels were studied. The parameters measured by the ELISA method were studied in the Thermo Fisher Scientific Multiscan Go (Finland) device at the Hatay Mustafa Kemal University Medical Faculty Medical Biochemistry USA ELISA Laboratory. Wholehouse and One Way Anova analysis methods were used to compare the results.

RESULTS

There were significant differences in E-Selectin, P-Selectin, ICAM-1 and LRG-1 values between the groups (p < 0.05). There was a significant difference between the vaginal birth (VB) and previa/percreata (PP) groups in terms of E-Selectin (p = 0.038). In terms of P-Selectin, there was a significant difference between the C/S and previa/percreata (PP) groups (p < 001). P-Selectin was higher in the previa/percreata (PP) group. There was a significant difference between the Vaginally birth (VB), C/S group (p = 0.041) and the vaginal birth (VB), previa/percreata (PP) group (p = 0.013) in terms of ICAM-1, but there was no significant difference between the C/S and previa/percreata (PP) groups. In terms of LRG-1, there was a significant difference between all 3 groups (p < 0.05).

DISCUSSION

A recent study investigated the potential modulatory effects of trans-resveratrol (RSV), arginase and endothelial dysfunction biomarkers in patients with PE. Another reflection of endothelial dysfunction in PE is increased endothelial activation biomarkers such as intercellular adhesion molecule-1 (ICAM-1), von Willebrand factor (vWF), and Caspase-3 (CASP-3). The study, regarding vWF expression, the preeclampsia (PE) group showed higher levels compared to endothelial cells incubated with healty pregnant (HP) plasma [Bueno-Pereira et al 2022 Antioxidants 2111]. From this and similar studies, the hypothesis that the role of cell adhesion molecules in endothelial damage may be the underlying cause of invasion and location anomalies emerges. This hypothesis is the starting point of our study.

CONCLUSIONS

In our study, all adhesion molecules except V-CAM-1 were found to be significantly higher in the previa/percreata (PP) group. E-Selectin and LRG-1 adhesion molecules were found to be significantly higher even in C/S patients compared to normal delivery. As a result; these adhesion molecules can be studied as a marker in previa/percreata (PP) patients.

The Update Immune-Regulatory Role of Pro- and Anti-Inflammatory Cytokines in Recurrent Pregnancy Losses

Recurrent pregnancy losses (RPL) is a common reproductive disorder with various underlying etiologies. In recent years, rapid progress has been made in exploring the immunological mechanisms for RPL. A propensity toward Th2 over Th1 and regulatory T (Treg) over Th17 immune responses may be advantageous for reproductive success. In women with RPL and animals prone to abortion, an inordinate expression of cytokines associated with implantation and early embryo development is present in the endometrium or decidua secreted from immune and non-immune cells. Hence, an adverse cytokine milieu at the maternal-fetal interface assaults immunological tolerance, leading to fetal rejection. Similar to T cells, NK cells can be categorized based on the characteristics of cytokines they secrete. Decidual NK (dNK) cells of RPL patients exhibited an increased NK1/NK2 ratio (IFN-γ/IL-4 producing NK cell ratios), leading to pro-inflammatory cytokine milieu and increased NK cell cytotoxicity. Genetic polymorphism may be the underlying etiologies for Th1 and Th17 propensity since it alters cytokine production. In addition, various hormones participate in cytokine regulations, including progesterone and estrogen, controlling cytokine balance in favor of the Th2 type. Consequently, the intricate regulation of cytokines and hormones may prevent the RPL of immune etiologies. Local or systemic administration of cytokines or their antagonists might help maintain adequate cytokine milieu, favoring Th2 over Th1 response or Treg over Th17 immune response in women with RPL. Herein, we provided an updated comprehensive review regarding the immune-regulatory role of pro- and anti-inflammatory cytokines in RPL. Understanding the roles of cytokines involved in RPL might significantly advance the early diagnosis, monitoring, and treatment of RPL.

Inflammation-Related Molecules at the Maternal-Fetal Interface during Pregnancy and in Pathologically Altered Endometrium

The blastocyst expresses paternally derived alloantigens and induces inflammation during implantation. However, it is necessary for the onset of pregnancy. An abnormal response might result in a pathological course of pregnancy or pregnancy failure. On the other hand, a state of maternal immune tolerance is necessary to ensure the normal development of pregnancy by suppressing inflammatory processes. This article discusses recognized mechanisms and the significance of inflammatory processes for embryo implantation and pregnancy establishment. We would also like to present disorders involving excessive inflammatory response and their influence on events occurring during embryo implantation. The chain of correlation between the processes responsible for embryo implantation and the subsequent physiological course of pregnancy is complicated. Many of those interrelationships are still yet to be discovered. Undoubtedly, their recognition will give hope to infertile couples for the emergence of new treatments that will increase the chance of giving birth to a healthy child.

Prenatal stress, anxiety and depression alter transcripts, proteins and pathways associated with immune responses at the maternal-fetal interface†

During pregnancy, the immune system is modified to allow developmental developmental tolerance of the semi-allogeneic fetus and placenta to term. Pregnant women suffering from stress, anxiety and depression show dysfunctions of their immune system that may be responsible for fetal and/or newborn disorders, provided that provided that placental gene regulation is compromised. The present study explored the effects of maternal chronic self-perceived stress, anxiety and depression during pregnancy on the expression of immune related-genes and pathways in term placenta. Pregnancies were clinically monitored with the Beck's Anxiety Inventory (BAI) and Edinburgh Postnatal Depression Scale (EPDS). A cutoff threshold for BAI/EPDS of 10 divided patients into two groups: Index group (≥10, n = 11) and a Control group (<10, n = 11), whose placentae were sampled at delivery. The placental samples were subjected to RNA-Sequencing, demonstrating that stress, anxiety and depression during pregnancy induced a major downregulation of placental transcripts related to immune processes such as T-cell regulation, interleukin and cytokine signaling or innate immune responses. Expression differences of main immune related genes such as CD46, CD15, CD8α & β ILR7α and CCR4 among others, were found in the index group (P < 0.05). Moreover, the key immune-like pathway involved in humoral and cellular immunity named "Primary immunodeficiency" was significantly downregulated in the index group compared to controls. Our results show that mechanisms ruling immune system functions are compromised at the maternal-fetal interface following self-perceived depressive symptoms and anxiety during pregnancy. These findings may help unveil mechanisms ruling the impact of maternal psychiatric symptoms and lead to new prevention/intervention strategies in complicated pregnancies.

A Critical Review and Scientific Prospective on Contraceptive Therapeutics from Ayurveda and Allied Ancient Knowledge

Commonly used synthetic or prescribed hormonal drugs are known to interfere with the endocrine system and may have adverse reproductive, neurological, developmental, and metabolic effects in the body. These may also produce adverse effects such as polycystic ovarian disorder, endometriosis, early puberty, infertility or toxicity to gonads, testicular germ cell cancer, breast or prostate cancer, brain developmental problems, and even birth defects. Globally, the emergence of renewed interest in natural products for reproductive health is on the rise, which offers opportunities for new contraceptive developments. The search for alternate, safer contraceptive products or agents of natural origin is of scientific interest. Ayurvedic classical texts offer knowledge and information about the reproductive function and therapeutics including those for enhancement and limiting male and female fertility. Review of ancient, medieval, and recent—including texts on erotica that provide information on approaches and large numbers of formulations and drugs of plant, mineral or animal origin—claimed to have sterilizing, contraceptive, abortifacient, and related properties is presented. Few among these are known to be toxic and few are not so common. However, most of the formulations, ingredients, or modes of administration have remained unattended to, due to issues related to consumer compliance and limitations of standardization and lack of appropriate validation modalities. Several of these ingredients have been studied for their phytoconstituents and for the variety of pharmacological activities. Efforts to standardize several classical dosage forms and attempts to adapt to modern technologies have been made. List of formulations, ingredients, and their properties linked with known constituents, pharmacological, biological, and toxicity studies have been provided in a series of tables. The possible effectiveness and safety of selected formulations and ingredients have been examined. Suggestions based on new drug delivery systems integrated with advances in biotechnology, to provide prospects for new therapeutics for contraception, have been considered. Ayurveda is built on a holistic paradigm of biological entity rather than limited gonadal functions. Graphic presentation of a few carefully chosen possibilities has been depicted. New approaches to standardization and ethnopharmacological validation of natural contraceptive therapeutics may offer novel mechanisms and modalities and therapeutic opportunities to satisfy unmet needs of contraception.

Therapeutic Targeting of IL-11 for Chronic Lung Disease

Interleukin (IL)-11 was originally recognized as an immunomodulatory and hematopoiesis-inducing cytokine. However, although IL-11 is typically not found in healthy individuals, it is now becoming evident that IL-11 may play a role in diverse pulmonary conditions, including IPF, asthma, and lung cancer. Additionally, experimental strategies targeting IL-11, such as humanized antibodies, have recently been developed, revealing the therapeutic potential of IL-11. Thus, further insight into the underlying mechanisms of IL-11 in lung disease may lead to the ability to interfere with pathological conditions that have a clear need for disease-modifying treatments, such as IPF. In this review, we outline the effects, expression, signaling, and crosstalk of IL-11 and focus on its role in lung disease and its potential as a therapeutic target.

Prednisolone Alters Endometrial Decidual Cells and Affects Decidual-Trophoblast Interactions

Poor pregnancy outcomes such as recurrent pregnancy loss (RPL) and preeclampsia are associated with impaired decidualization and abnormal trophoblast invasion. Emerging evidence suggests that use of corticosteroids, including prednisolone affects fertility by altering uterine function and may be associated with preeclampsia incidence. In this study, using primary and gestational-age appropriate tissue, we aimed to define the effect of prednisolone on human endometrial stromal fibroblast (hESF) decidualization and determine whether hESF decidualization in the presence of prednisolone would alter hESF regulation of trophoblast function. We found that prednisolone treatment reduced hESF cytokine expression (IL6, IL11, IL18, LIF, and LIFR) but had no effect on hESF expression or secretion of the classic markers of decidualization [prolactin (PRL) and IGFBP1]. Using proteomics we determined that prednisolone altered decidualized hESF protein production, enriching hESF proteins associated with acetylation and mitrochondria. Conditioned media from hESF decidualized in the presence of prednisolone significantly enhanced trophoblast outgrowth and trophoblast mRNA expression of cell motility gene PLCG1 and reduced trophoblast production of PGF. Prednisolone treatment during the menstrual cycle and 1st trimester of pregnancy might alter decidual interactions with other cells, including invasive trophoblast.

Cytokine imbalance at materno-embryonic interface as a potential immune mechanism for recurrent pregnancy loss

Recurrent pregnancy loss (RPL) is a prominent reproductive disease that distresses about 2%-5% of couples. RPL is the loss of two or more successive spontaneous pregnancies prior to the 20th week of embryo development. The commencement of pregnancy necessitates implantation of the embryo into responsive maternal decidua synchronized with the process of placentation, decidual and myometrial trophoblast incursion as well as refashioning of spiral blood arteries of uterus. The collapse of any of the processes fundamental for pregnancy success may result into an array of pregnancy problems including spontaneous pregnancy loss. Endometrium of human female manufactures an extensive range of cytokines during the proliferative and secretory stage of the menstrual cycle. These endometrial cytokines are thought as major players for making the uterus ready for embryo implantation and placental development during pregnancy. Decidual cytokines regulate the invasion of trophoblast and remodeling of spiral arteries as well as take part in immune suppression to accomplish the pregnancy. Deterrence of maternal rejection of embryo needs a regulated milieu, which takes place essentially at the embryo-maternal interface and the tissues of the uterus. The reasons of RPL remain anonymous in a large number of cases that lead to difficulties in management and severe trauma in couples. Cytokine modulatory therapies have been shown promising for preventing RPL. Further study of novel factors is wanted to establish more effective RPL treatment protocols. The present study aims to review the outcome of cytokine breach at materno-embryonic interface and the efficacy of cytokine modulatory therapies in RPL.

Structural Understanding of Interleukin 6 Family Cytokine Signaling and Targeted Therapies: Focus on Interleukin 11

Cytokines are small signaling proteins that have central roles in inflammation and cell survival. In the half-century since the discovery of the first cytokines, the interferons, over fifty cytokines have been identified. Amongst these is interleukin (IL)-6, the first and prototypical member of the IL-6 family of cytokines, nearly all of which utilize the common signaling receptor, gp130. In the last decade, there have been numerous advances in our understanding of the structural mechanisms of IL-6 family signaling, particularly for IL-6 itself. However, our understanding of the detailed structural mechanisms underlying signaling by most IL-6 family members remains limited. With the emergence of new roles for IL-6 family cytokines in disease and, in particular, roles of IL-11 in cardiovascular disease, lung disease, and cancer, there is an emerging need to develop therapeutics that can progress to clinical use. Here we outline our current knowledge of the structural mechanism of signaling by the IL-6 family of cytokines. We discuss how this knowledge allows us to understand the mechanism of action of currently available inhibitors targeting IL-6 family cytokine signaling, and most importantly how it allows for improved opportunities to pharmacologically disrupt cytokine signaling. We focus specifically on the need to develop and understand inhibitors that disrupt IL-11 signaling.

Two patterns of cytokine production by placental macrophages

INTRODUCTION

Macrophages participate in the regulation immune and morphogenetic events in the placenta. However, these roles remain unclear for placental macrophages (Hofbauer cells). The aims of this study were to characterize the consecutive steps of cytokine production (intracellular synthesis and secretion) in placental macrophages in early and late gestation and to compare the secretory profiles of placental macrophages and villous tissue.

METHODS

Macrophages and villous tissue were isolated from placentas obtained from normal pregnancies at either 9-12 or 38-40 weeks of gestation. Intracellular cytokines were determined by flow cytometry after staining with monoclonal antibodies. Secreted cytokines were quantified by cytometric bead array and ELISA.

RESULTS

Two patterns of cytokine production were revealed in placental macrophages. Cytokines in the first group (IL-1, IL-6, IL-8, IL-10, TNFα) demonstrated low basal production and were stimulated by bacterial endotoxin. Cytokines in the second group (IL-11, IL-17A, IL-17F, TGF-β, VEGF) were characterized by constitutive production and did not respond to stimulation. Gestational age-dependent changes were observed: basal secretion of TNFα and IL-8 increased whereas IL-11 and IL-17 secretion decreased in third-trimester macrophages compared with the first-trimester cells. Comparison of cytokine production at the cellular and tissue levels suggested the contribution of the placental macrophages both in intraplacental and extraplacental cytokine production.

DISCUSSION

It would be safe to assume that the two patterns of cytokine production, revealed in our study, correspond to two regulatory roles of placental macrophages: "immune" and "morphogenetic". The inflammatory phenotype of macrophages is attenuated in early gestation and increases with the progression of pregnancy. The cytokines of the first group supposedly contribute to both local and extraplacental levels, whereas the cytokine effects of the second group are more likely confined to the placental tissue.

Interleukin 11 is upregulated in preeclampsia and leads to inflammation and preeclampsia features in mice

Preeclampsia is a dangerous pregnancy complication, which is often associated with fetal growth restriction and can have serious life-long effects for both mother and baby. While the establishment of the placenta in the first trimester is the sentinel event in the development of preeclampsia little is known of the critical mechanisms of placentation that lead to the syndrome. Locally produced inflammatory cytokines are thought to play a role in the development of preeclampsia. This review summarizes the evidence that interleukin 11 is dysregulated in preeclampsia and contributes to the initiation of preeclampsia via effects on placentation. It discusses the benefits and drawbacks of targeting IL11 as a novel treatment option for preeclampsia.

A phytoestrogen supplement prevents the altered gene expression associated with pregnancy implantation induced by IL-1β in endometrial epithelial cells

Phytoestrogens stimulate expression of the uterine estrogen receptor and regulate uterine functions in reproductive tissues. However, comprehensive understanding of the beneficial impacts of phytoestrogens on uterine biology at the molecular level remains unexplored. Interleukin-1β (IL-1β) expression is increased in the inflamed decidua and is associated with first trimester pregnancy loss. AglyMax-Sup has the same composition as that of the phytoestrogen supplement AglyMax but with added vitamins and other components. Expression of genes associated with implantation may be enhanced by AglyMax-Sup compared with AglyMax. We tested the hypothesis that AglyMax-Sup has greater effects on implantation compared with AglyMax, using RT-PCR and Western blotting in the endometrial epithelial cell line. Furthermore, we investigated the protective effect of AglyMax-Sup on IL-1βinduced changes in estrogen-responsive gene expression in endometrial epithelial cells. The purpose of this study was to compare the effects of the phytoestrogen supplement AglyMax-Sup with those of AglyMax on estrogen-responsive gene expression. AglyMax and AglyMax-Sup significantly (p<0.05) induced gene expression of glycodelin-A, HoxA10, IL-11, LIF, MEG-E8 and TGFβ1. AglyMax-Sup induced high levels of these genes compared with the levels induced by AglyMax. The enhanced expression of LIF, IL-11, integrin αV, and HOXA10 induced by AglyMax-Sup was abolished by the ER antagonist fulvestrant and the ERK inhibitor PD98059. Meanwhile, IL-1β inhibited progesterone plus estrogen-induced TGFβ1, glycodelin-A, HOXA10, and integrin αV expression. IL-1β-induced suppression of these expression was reversed by AglyMax-Sup. These results indicate that expression of genes associated with implantation may be increased by AglyMax-Sup compared with AglyMax. AglyMax-Sup might abrogate IL-1β-mediated changes that can affect embryo implantation via the MAPK pathway.

Interleukin 11: similar or opposite roles in female reproduction and reproductive cancer?

During placental development and carcinogenesis, cell invasion and migration are critical events in establishing a self-supporting vascular supply. Interleukin (IL)-11 is a pleiotropic cytokine that affects the invasive and migratory capabilities of trophoblast cells that form the placenta during pregnancy, as well as various malignant cell types. The endometrium is the site of embryo implantation during pregnancy; conversely, endometrial carcinoma is the most common gynaecological malignancy. Here, we review what is known about the role of IL-11 in trophoblast function and in gynaecological malignancies, focusing primarily on the context of the uterine environment.

Chronic endometritis and infertility

Chronic endometritis (CE) is a condition involving the breakdown of the peaceful co-existence between microorganisms and the host immune system in the endometrium. A majority of CE cases produce no noticeable signs or mild symptoms, and the prevalence rate of CE has been found to be approximately 10%. Gynecologists and pathologists often do not focus much clinical attention on CE due to the time-consuming microscopic examinations necessary to diagnose CE, its mild clinical manifestations, and the benign nature of the disease. However, the relationship between CE and infertility-related conditions such as repeated implantation failure and recurrent miscarriage has recently emerged as an area of inquiry. In this study, we reviewed the literature on the pathophysiology of CE and how it may be associated with infertility, as well as the literature regarding the diagnosis and treatment of CE. In addition, we discuss the value of hysteroscopic procedures in the diagnosis and treatment of CE.

IL-11 signaling as a therapeutic target for cancer

IL-11 is a member of the IL-6 family of cytokines. While it was discovered over 20 years ago, we have very little understanding of the role of IL-11 during normal homeostasis and disease. Recently, IL-11 has gained interest for its newly recognized role in the pathogenesis of diseases that are attributed to deregulated mucosal homeostasis, including gastrointestinal cancers. IL-11 can increase the tumorigenic capacity of cells, including survival of the cell or origin, proliferation of cancerous cells and survival of metastatic cells at distant organs. Here we outline our current understanding of IL-11 biology and recent advances in our understanding of its role in cancer. We advocate that inhibition of IL-11 signaling may represent an emerging therapeutic opportunity for numerous cancers.

Interleukin-11 alters placentation and causes preeclampsia features in mice

Preeclampsia (PE) is a pregnancy-specific disorder characterized by hypertension and proteinuria after 20 wk gestation. Abnormal extravillous trophoblast (EVT) invasion and remodeling of uterine spiral arterioles is thought to contribute to PE development. Interleukin-11 (IL11) impedes human EVT invasion in vitro and is elevated in PE decidua in women. We demonstrate that IL11 administered to mice causes development of PE features. Immunohistochemistry shows IL11 compromises trophoblast invasion, spiral artery remodeling, and placentation, leading to increased systolic blood pressure (SBP), proteinuria, and intrauterine growth restriction, although nonpregnant mice were unaffected. Real-time PCR array analysis identified pregnancy-associated plasma protein A2 (PAPPA2), associated with PE in women, as an IL11 regulated target. IL11 increased PAPPA2 serum and placental tissue levels in mice. In vitro, IL11 compromised primary human EVT invasion, whereas siRNA knockdown of PAPPA2 alleviated the effect. Genes regulating uterine natural killer (uNK) recruitment and differentiation were down-regulated and uNK cells were reduced after IL11 treatment in mice. IL11 withdrawal in mice at onset of PE features reduced SBP and proteinuria to control levels and alleviated placental labyrinth defects. In women, placental IL11 immunostaining levels increased in PE pregnancies and in serum collected from women before development of early-onset PE, shown by ELISA. These results indicate that elevated IL11 levels result in physiological changes at the maternal-fetal interface, contribute to abnormal placentation, and lead to the development of PE. Targeting placental IL11 may provide a new treatment option for PE.

The evolution of embryo implantation

Embryo implantation varies widely in placental mammals. We review this variation in mammals with a special focus on two features: the depth of implantation and embryonic diapause. We discuss the two major types of implantation depth, superficial and interstitial, and map this character on a well-resolved molecular phylogenetic tree of placental mammals. We infer that relatively deep interstitial implantation has independently evolved at least eight times within placental mammals. Moreover, the superficial type of implantation represents the ancestral state for placental mammals. In addition, we review the genes involved in various phases of implantation, and suggest a future direction in investigating the molecular evolution of implantation-related genes.

The chrondroitin sulfate proteoglycan (CSPG4) regulates human trophoblast function

INTRODUCTION

Trophoblast growth and invasion of the uterine endometrium are critical events during placentation and are tightly regulated by locally produced factors. Abnormal placentation can result in early miscarriage or preeclampsia and intrauterine growth restriction, leading to impaired fetal and/or maternal health. Chondroitin sulfate proteoglycan 4 (CSPG4) is involved in cancer cell migration and invasion, processes which are critical during placentation but unlike in cancer, trophoblast invasion is highly regulated. CSPG4 expression and function in trophoblast is unknown. We determined CSPG4 expression in human first trimester placenta and implantation sites, and investigated whether CSPG4 influenced proliferation, migration and invasion of a human extravillous trophoblast (EVT) cell line (HTR8/SVneo cells) as a model for extravillous trophoblast (EVT).

METHODS AND RESULTS

Immunoreactive CSPG4 localized to EVT cells in the trophoblast shell, subpopulations of interstitial EVT cells within the decidua and cytotrophoblast cells in placental villi. In HTR8/SVneo cells, siRNA knockdown of CSPG4 stimulated proliferation and decreased migration/invasion. In primary first trimester placental villi explants two cytokines, interleukin 11 (IL11) and leukemia inhibitory factor (LIF) with known roles in trophoblast function, stimulated CSPG4 mRNA expression and immunoreactive protein in the cyotrophoblast.

DISCUSSION AND CONCLUSION

This is the first demonstration of the production and function of CSPG4 in human placentation. These data suggest that locally produced CSPG4 stimulates human EVT migration and invasion and suggests that IL11 and LIF regulate villous cytotrophoblast differentiation towards the invasive phenotype at least in part via CSPG4.

Altered transcriptional regulation of cytokines, growth factors, and apoptotic proteins in the endometrium of infertile women with chronic endometritis

PROBLEM

Chronic endometritis (CE) is a poorly investigated and probably underestimated pathology, which may cause abnormal uterine bleeding (AUB), pain, and reproductive failures. Due to undefined symptoms and the normal presence of leukocytes in the endometrial mucosa, diagnosis may be missed. Fluid hysteroscopy is a reliable technique for diagnosing this pathology. Few data exist on the biochemical and paracrine alterations that occur in the endometrium of women diagnosed with CE. The aim of the study was to find molecular modification in endometrium related to CE.

METHOD OF STUDY

Sixteen women with hysteroscopic and histological diagnosis of CE and 10 healthy women as controls were enrolled. We compared the endometrial expression profile of 25 genes encoding proteins involved in the inflammatory response, proliferation, and apoptosis in endometrium during implantation window, using high-throughput real-time RT-PCR.

RESULTS

In women with CE, the endometrial expression of some genes was significantly altered. In particular, IGFBP1, BCL2, and BAX were up-regulated, while IL11, CCL4, IGF1, and CASP8 were down-regulated.

CONCLUSION

The altered gene endometrial expression may explain the impaired endometrial receptivity and the finding of endometrial hyperplastic lesions in women affected by CE.

Understanding the link between the IL-6 cytokine family and pregnancy: implications for future therapeutics

Cytokines are involved in almost all processes during the menstrual cycle, the fertilization period and pregnancy. They are expressed in numerous reproduction-related body fluids and tissues. Disorders of cytokine expression patterns may cause pregnancy pathologies. Therefore, cytokines have the potential as new biomarkers in different body compartments for a variety of such pathologies. Furthermore, cytokines may also serve to treat fertility and pregnancy disorders. The IL-6-like family of cytokines is an intensively investigated group of cytokines with well-accepted functions in fertility and pregnancy. This article summarizes current knowledge on IL-6-like cytokines in regard of their role in reproduction and their potential for new strategies in the treatment of reproductive pathologies.

Preeclampsia-related increase of interleukin-11 expression in human decidual cells

Preeclampsia is associated with increased systemic inflammation and superficial trophoblast invasion, which leads to insufficient uteroplacental blood flow. Interleukin (IL)-11 mediates pro- and anti-inflammatory processes and facilitates decidualization. To identify IL11 expression in vivo at the maternal-placental interface in preeclampsia and control specimens and to evaluate the regulatory effects of tumor necrosis factor-α (TNF) and IL1B, cytokines elevated in preeclampsia, on IL11 levels in first trimester decidual cells in vitro, placental sections were immunostained for IL11. Leukocyte-free first trimester decidual cells were incubated with estradiol (E(2))±10(-7)  mol/l medroxyprogesterone acetate±TNF or IL1B± inhibitors of the p38 MAP kinase (p38 MAPK), nuclear factor-κ B (NFKB), or protein kinase C (PKC) signaling pathways. An ELISA assessed secreted IL11 levels, and quantitative RT-PCR measured IL11 mRNA. IL11 immunoreactivity in placental sections was significantly higher in the cytoplasm of preeclamptic decidual cells versus gestational age-matched controls. Compared to decidual cells, IL11 immunostaining in neighboring trophoblast is lower, perivascular, and not different between control and preeclamptic specimens. TNF and IL1B enhanced levels of IL11 mRNA and secreted IL11 in cultured decidual cells. Specific inhibitors of the p38 MAPK and NFKB, but not PKC signaling pathways, reduced the stimulatory effect of IL1B. Expression of decidual IL11 is increased in preeclampsia and suggests a role for IL11 in the pathogenesis of preeclampsia.

Family planning: today and in the future

This review covers the state of contraceptive development noting new entries in the clinic (mainly steroidal and different delivery methods) and novel leads for nonsteroidal female- and male-methods in the pipeline. The time taken to market and the absence of partnerships with industry are stressed as major factors for the slow progress in their development.

Fetomaternal immunotolerance

Implantation of mammalian conceptus in uterine cavity is the result of evolutionary adaptation, through high level of physiological procedures to ensure its success. However the majority of pregnancy losses occur before or during implantation. It is expected that exploring and defining the molecular and physiological road map during the crucial time of implantation will enable us to decode and effectively treat fertility defects. Immunological, hormonal and molecular factors participate in the feto-maternal cross talk during implantation and designate the effectiveness of the process. The atypical expression of major histocompatibility complex and other protein-antigens, such as Fas/FasL and petformin in human trophoblast, the modified function of cellular constituents of the feto-maternal interface, as well as the specific role of some hormones and cytokines, represent substantive parameters of feto-maternal immunotolerance during implantation.

Interleukin-11 increases invasiveness of JEG-3 choriocarcinoma cells by modulating STAT3 expression

Amongst the interleukin-6 (IL-6) family of cytokines, leukemia inhibitory factor (LIF) has been shown to promote trophoblast invasion and proliferation. In the present study interleukin-11 (IL-11), another member of the IL-6 family, was investigated for its role in regulating invasion, migration and proliferation of JEG-3 choriocarcinoma cells. JEG-3 cells, like extra villous trophoblast (EVT), express mRNA transcripts encoding IL-11 and IL-11 receptor-alpha (IL-11Ralpha). Treatment of JEG-3 cells with IL-11 led to an increase in invasion across Matrigel extracellular matrix without an increase in proliferation. There was a dose-dependent increase in activation of STAT3 under the influence of IL-11 with maximum Tyr705 phosphorylation by 10min. In addition, treatment of JEG-3 cells with IL-11 for 24h led to an increase in expression of unphosphorylated STAT1 and STAT3. Analysis of the nuclear fraction showed an increased localization of STAT3 following IL-11 treatment while STAT1 was absent. Silencing the expression of STAT3 by siRNA caused a 25% reduction in invasion compared to control cells, however this was not significant. Furthermore, treatment of STAT3-silenced JEG-3 cells with IL-11 led to a significant increase in invasion compared to STAT3-silenced cells without cytokine, but this was not significant compared to non-transfected control cells. Silencing the expression of gp130 but not of IL-6R abrogated the increase in invasiveness of JEG-3 cells following IL-11 treatment. In conclusion, activation and upregulation of STAT3 appears to be critical for the IL-11-mediated increase in invasiveness of JEG-3 cells.

Leukemia inhibitory factor and interleukin-11: critical regulators in the establishment of pregnancy

Blastocyst implantation into a receptive endometrium is critical to the establishment of pregnancy and is tightly regulated by factors within the blastocyst-endometrial micro-environment. Leukemia inhibitory factor (LIF) and interleukin-11 (IL11) have key roles during implantation. Female mice with a null mutation in the LIF or IL11RA gene are infertile due to a complete failure of implantation or a defective differentiation/decidualization response to the implanting blastocyst, respectively. LIF and IL11 deficiency during pregnancy is associated with infertility and miscarriage in women. Numerous cell populations at the maternal-fetal interface are regulated by LIF/IL11 including the endometrial epithelium, decidualizing stroma, placental trophoblasts and leukocytes. This review focuses on the roles of LIF/IL11 during early pregnancy and highlights their potential as contraceptive targets and therapeutic agents for infertility.

The role of growth factors and cytokines during implantation: endocrine and paracrine interactions

Implantation, a critical step for establishing pregnancy, requires molecular and cellular events resulting in uterine growth and differentiation, blastocyst adhesion, invasion, and placental formation. Successful implantation requires a receptive endometrium, a normal and functional embryo at the blastocyst stage, and a synchronized dialogue between maternal and embryonic tissues. In addition to the well-characterized role of sex steroids, the complexity of embryo implantation and placentation is exemplified by the number of cytokines and growth factors with demonstrated roles in these processes. Disturbances in the normal expression and action of these cytokines result in an absolute or partial failure of implantation and abnormal placental formation in mice and human. Members of the gp130 cytokine family, interleukin-11 (IL-11) and leukemia inhibitory factor, the transforming growth factor beta superfamily, the colony-stimulating factors, and the IL-1 and IL-15 systems are crucial molecules for a successful implantation. Chemokines are also important, both in recruiting specific cohorts of leukocytes to the implantation site and in trophoblast trafficking and differentiation. This review provides discussion of the embryonic and uterine factors that are involved in the process of implantation in autocrine, paracrine, and/or juxtacrine manners at the hormonal, cellular, and molecular levels.

Interleukin 11 inhibits human trophoblast invasion indicating a likely role in the decidual restraint of trophoblast invasion during placentation

Successful pregnancy depends on the precise regulation of extravillous trophoblast (EVT) invasion into the uterine decidua, primarily by decidua-derived factors. In humans, during early pregnancy interleukin 11 (IL11) is maximally expressed in the decidua, with its receptor, IL11 receptor alpha (IL11RA), also identified on invasive EVTs in vivo. Although a role for IL11 in EVT migration has been established, whether it also plays a role in regulating EVT invasion is unknown. We investigated whether IL11 influences human EVT invasion and the signaling pathways and underlying mechanisms that may be involved, using the HTR-8/SVneo immortalized EVT cell line and primary EVTs as models for EVTs. Interleukin 11 (100 ng/ml) significantly inhibited invasion of EVT cells by 40% to 60% (P < 0.001). This effect was abolished by inhibitors of signal transducer and activator of transcription 3 (STAT3) but not of mitogen-activated protein kinase (MAPK) pathways. Interleukin 11 (100 ng/ml) had no effect on matrix metallopeptidases 2 and 9 (MMP2 and MMP9), tissue inhibitors of MMP (TIMP1, TIMP2, and TIMP3), plasminogen activator urokinase (PLAU), plasminogen activator urokinase receptor (PLAUR), and serpin peptidase inhibitors 1 and 2 (SERPINE1 and SERPINE2) in EVT-conditioned media and/or cell lysates. Interleukin 11 (100 ng/ml) also did not regulate EVT cell adhesion or integrin expression. These data demonstrate that IL11 inhibits human EVT invasion via STAT3, indicating a likely role for IL11 in the decidual restraint of EVT invasion during normal pregnancy.

As the world grows: contraception in the 21st century

Contraceptives that are readily available and acceptable are required in many poorer countries to reduce population growth and in all countries to prevent maternal morbidity and mortality arising from unintended pregnancies. Most available methods use hormonal steroids or are variations of barrier methods. Reports from several fora over the last 12 years have emphasized the number of unwanted pregnancies and resultant abortions, which indicate an unmet need for safe, acceptable, and inexpensive contraceptive methods. This unmet need can be assuaged, in part, by development of new nonhormonal contraceptive methods. This Review addresses the contribution that the "omic" revolution can make to the identification of novel contraceptive targets, as well as the progress that has been made for different target molecules under development.

Basic aspects of implantation

Implantation, a critical step for establishing pregnancy, requires molecular and cellular events resulting in healthy uterine growth and differentiation, blastocyst adhesion, invasion and placental formation. Successful implantation requires a receptive endometrium, a normal and functional embryo at the blastocyst stage and a synchronized dialogue between maternal and embryonic tissues. In addition to the main role of sex steroids, the complexity of embryo implantation and placentation is exemplified by the number of cytokines and growth factors with demonstrated roles in these processes. Disturbances of the normal expression and action of these cytokines result in absolute or partial failure of implantation and abnormal placental formation in mice and humans. Members of the gp130 cytokine family, interleukin (IL)-11 and leukaemia inhibitory factor, the transforming growth factor-beta superfamily, colony-stimulating factors, and the IL-1 and IL-15 systems are all crucial for successful implantation. In addition, chemokines are important both in recruiting specific cohorts of leukocytes to the implantation site, and in trophoblast trafficking and differentiation. This review provides discussion on embryonic and uterine factors that are involved in the process of implantation in autocrine, paracrine and/or juxtacrine manners at hormonal, cellular, and molecular levels.

Interleukin-11 promotes migration, but not proliferation, of human trophoblast cells, implying a role in placentation

Trophoblast growth and invasion of the uterine endometrium are critical events during placentation and are tightly regulated by factors produced within the trophoblast-endometrial microenvironment. Deficiencies in placentation can result in early miscarriage or preeclampsia and intrauterine growth restriction, leading to impaired fetal health. The latter has been linked to major adult health disorders. IL-11 is essential for blastocyst implantation in mice. In humans, IL-11 and its receptor IL-11 receptor alpha (IL-11Ralpha) are maximally expressed in the decidua and chorionic villi during early pregnancy; however, the role of IL-11 in trophoblast function is unknown. Therefore, we examined whether IL-11Ralpha is expressed in human first trimester implantation sites, and whether IL-11 influences proliferation and migration of a human extravillous trophoblast (EVT)-hybridoma cell line and primary EVT cells, used as models for EVT. Immunoreactive IL-11Ralpha localized to subpopulations of interstitial and endovascular EVT cells in vivo. In EVT cells in vitro, IL-11: 1) stimulated phosphorylation of signal transducer and activator of transcription-3; 2) was without effect on EVT cell proliferation; and 3) stimulated significant migration of EVT-hybridoma cells (no endogenous IL-11), whereas in primary EVT, blocking endogenous IL-11 inhibited EVT migration by 30-40%. These data demonstrate that IL-11 stimulates human EVT migration, but not proliferation, likely via signal transducer and activator of transcription-3, indicating an important role for IL-11 in placentation.

Mechanisms of implantation

Successful embryo implantation in mammals requires the co-ordinated development of a blastocyst competent to implant and an adhesive endometrium. Given the indispensable role of implantation for the furtherance of the species, a number of molecular mechanisms have evolved to regulate the process. A variety of molecules, produced by embryo as well as maternal tissue participates in the cross-talk between the implanting blastocyst and the endometrium. The interplay between the various molecules and the routes in which they are involved is beginning to be elucidated. Because impaired implantation represents the most important limiting factor in the establishment of pregnancy, it is believed that research in the field will allow clinicians to improve the respective rates. This paper reviews certain groups of molecules that are considered to have key roles in the mechanisms of implantation.

Implantation in the macaque: expansion of the implantation site during the first week of implantation

Data accumulated over several years of investigating implantation in macaque monkeys have been used to estimate the rate of expansion of the initial implantation site, the increase in volume of the site, and the rate of arterial invasion by cytotrophoblast columns. In addition the expansion of the secondary implantation site has also been estimated. The primary implantation site expands from an average diameter of 0.268 mm on day 10 to 4.93 mm on day 16-17. It expands in thickness from 0.064 mm on day 10 to 0.96 mm on day 16-17, and in volume from 0.0036 mm(3) on day 10 to 18.34 mm(3) on day 16-17. During this period of rapid expansion in extent and volume of the implantation site, trophoblast invades the endometrium, forms a lacunar stage, and initiates villus formation; consequently these very considerable changes in structure occur when the implantation is still very small yet growing rapidly. The secondary site expands from 0.23 mm in diameter on day 12 to 2.8mm on day 17. The rate of penetration of cytotrophoblast into endometrial arteries diminishes from 0.602 mm per day on day 12 to 0.171 mm per day on day 16, using the straight-line method of estimation. This diminution in rate is consistent with the hypothesis that cytotrophoblast cells generated at the anchoring villi migrate over cytotrophoblast cells that have attached to the endothelium of the endometrial arteries in advancing the intraluminal columns of trophoblast. It is hoped that the summaries provided will be useful to investigators using macaque monkeys to analyze aspects of implantation in primates.

Interleukin 11 signaling components signal transducer and activator of transcription 3 (STAT3) and suppressor of cytokine signaling 3 (SOCS3) regulate human endometrial stromal cell differentiation

The differentiation of endometrial stromal cells into decidual cells (decidualization) is critical for embryo implantation, but the mechanisms remain poorly defined. Numerous paracrine agents including IL-11 promote human endometrial stromal cell (HESC) decidualization. IL-11 signaling is transduced by the signal transducers and activators of transcription (STAT) proteins. Suppressors of cytokine signaling (SOCS) proteins are stimulated in response to cytokine-inducible STAT phosphorylation, acting in a negative-feedback mechanism to hinder cytokine receptor activity. This study examined the role of IL-11 signal transduction components in HESC decidualization in an ex vivo model. Cells were induced to differentiate with estrogen plus medroxyprogesterone acetate (E+P) or cAMP (assessed by prolactin secretion) and resulted in increased STAT3 and SOCS3. E+P maximally stimulated STAT3, whereas cAMP maximally stimulated SOCS3 during decidualization, suggesting E+P and cAMP differentially regulated the signaling components. IL-11 stimulated the phosphorylation (p) of STAT3 and SOCS3 mRNA and protein. Antiprogestin (onapristone) added to decidualizing cells attenuated STAT3 protein but increased SOCS3 mRNA and protein, suggesting regulation via both ligand-dependent and -independent progesterone-receptor pathways. SOCS3 overexpression in HESC reduced IL-11-induced pSTAT3 and retarded decidualization, indicating that SOCS3 is a critical regulator of differentiation. Immunoreactive pSTAT3 and SOCS3 were all present in decidualized stromal cells, epithelial cells, and leukocytes in human endometrium. These data support a role for IL-11 via pSTAT3 and SOCS3 in initiating and progressing decidualization.

Hormonal and cytokine regulation of early implantation

Implantation of the blastocyst into the endometrium is a delicately controlled process and a prerequisite for the furtherance of the mammalian species. A complex network of molecules is involved in preparing both the endometrium and blastocyst for a successful interaction. However, the exact molecular steps are poorly understood. Studies so far have shown that disruption of certain pathways results in fertility defects. Impaired implantation is currently considered to be the most important limiting factor for the establishment of viable pregnancies in assisted reproduction. It is expected that elucidating the molecular background of the process will enable accurate diagnosis and effective treatment of infertility.

Interleukin-11, IL-11 receptorα and leukemia inhibitory factor are dysregulated in endometrium of infertile women with endometriosis during the implantation window

Interleukin (IL)-11 is essential for embryo implantation in the mouse and evidence suggests it has a role in implantation in humans. This study has evaluated immunoreactive IL-11, IL-11 receptor (R) alpha and leukemia inhibitory factor (LIF) in endometrium of infertile women with endometriosis (I/E) and normal fertile women (controls) during the implantation window. Endometrial biopsies from I/E (N = 7) were timed from the LH surge and were post-ovulatory days (POD) 5-10. Control biopsies (N = 8) from women were between days 19 and 24 of the menstrual cycle. Staining intensity of IL-11, IL-11Ralpha and LIF evaluated using semi-quantitative immunohistochemistry scores. Immunoreactive IL-11, IL-11Ralpha and LIF were present predominantly in glandular epithelium, while luminal epithelium showed patchy staining. All controls stained positively for IL-11, IL-11Ralpha and LIF in glandular epithelium. IL-11 and IL-11Ralpha staining was absent from glandular epithelium in cohorts of I/E. LIF staining intensity in glandular epithelium was significantly lower in I/E compared to controls. The results suggest that reduced endometrial IL-11 and/or LIF may contribute to infertility in some endometriotic women.

Cytokines, chemokines and growth factors in endometrium related to implantation

The complexity of the events of embryo implantation and placentation is exemplified by the number and range of cytokines with demonstrated roles in these processes. Disturbance of the normal expression or action of these cytokines results in complete or partial failure of implantation and abnormal placental formation in mice or humans. Of known importance are members of the gp130 family such as interleukin-11 (IL-11) and leukaemia inhibitory factor (LIF), the transforming growth factor beta (TGFbeta) superfamily including the activins, the colony-stimulating factors (CSF), the IL-1 system and IL-15 system. New data are also emerging for roles for a number of chemokines (chemoattractive cytokines) both in recruiting specific cohorts of leukocytes to implantation sites and in trophoblast differentiation and trafficking. This review focuses on those cytokines and chemokines whose expression pattern in the human endometrium is consistent with a potential role in implantation and placentation and for which some relevant actions are known. It examines what is known of their regulation and action along with alterations in clinically relevant situations.

The possible mechanisms for the antifertility action of methanolic root extract of Rumex steudelii

BACKGROUND

The practice of traditional medicine for the control of fertility in most parts of Ethiopia is based on the uses of plant medicines for many years. Rumex steudelii Hochst (Polygonaceae), locally known as "Tult" or "Yeberemelas" is one of the traditionally used antifertility plants in Ethiopia. In our previous study, the methanolic extract of R. steudelii root was found to show antifertility activity in female rats.

OBJECTIVES

The present study focused further on the possible mechanisms of the antifertility effect of the methanolic extract of R. steudelii.

METHODS

The effect of the extract on implantation, the uterus weight of immature ovariectomized rats and serum estrogen-progesterone ratio was evaluated. Its effect on isolated guinea pig uterus in the presence and absence of uterine muscle contractions inhibitors was also assessed. Test for in vivo abortifacient effect was also carried out.

RESULTS

It was found that the extract decreased the number of implantation sites significantly. At a contraceptive dose, it was also observed to have no estrogenic activity in immature rat bioassay. The extract did not affect the serum estrogen-progesterone ratio. It produced concentration dependent increase in uterine muscle contractions similar to those of the standard drug, oxytocin. Incubation of the tissue with three uterine muscle contractions inhibitors revealed that the extract produced uterine contractions perhaps by activating muscarinic and/or histaminic receptors. The in vivo abortifacient effect was not seen upon administration of both lower and higher doses of the extract in pregnant rats.

CONCLUSION

All these observations suggest that the extract produced antifertility effect mainly by inhibiting implantation though antiestrogen, progesteron and uterotonic effects could as well be possible mechanisms.

The production of interleukin-11 and decidualization are compromised in endometrial stromal cells derived from patients with infertility

IL-11 signaling is critical for decidualization of the endometrial stroma in early pregnancy in the mouse. In this study, we investigate the function of IL-11 signaling in cAMP-induced decidualization of human endometrial stromal cells. We show that treatment of endometrial stromal cells with 8-bromo-cAMP (8-Br-cAMP) results in an increase in the levels of secreted IL-11, whereas levels of cell surface IL-11 receptor alpha are similar with or without 8-Br-cAMP treatment. The production of IL-11 correlates with the production of molecular markers of decidualization, prolactin and IGF-binding protein-1. The expression of these markers is inhibited when IL-11 signaling is specifically blocked in decidualizing endometrial stromal cells by the IL-11 antagonist W147A. We demonstrate that 8-Br-cAMP-induced endometrial stromal cells derived from patients with primary infertility produce lower levels of prolactin, IGF-binding protein-1, and IL-11 than cells derived from fertile women. Our results suggest that IL-11 expression is critically important during decidualization in the human endometrium, and that aberrant regulation of endometrial IL-11 production may be associated with some types of infertility.

Interleukin-11 expression: its significance in eutopic and ectopic human implantation

Embryo implantation and subsequent decidualization, trophoblast invasion and formation of a functional placenta are crucial for establishment and maintenance of pregnancy. Interleukin-11 signalling has been shown to be obligatory for adequate decidualization and trophoblast invasion in mice. Defects in IL-11 signalling in mice result in trophoblast over-invasion and fetal loss. The pathological situation of human tubal pregnancy resembles that of IL-11Ralpha(-/-) mice concerning these symptoms. As our interest is focused on the human early pregnancy, we compared IL-11 expression at the implantation site of ectopic tubal pregnancy (EP) to 1st and 2nd trimester of normal intrauterine pregnancies (IP), and to the normal cycling endometrium. The mRNA expression of IL-11 and IL-11Ralpha was analysed by semiquantitative RT-PCR. Protein expression was detected by western blotting and immunohistochemistry. IL-11Ralpha is expressed constitutively in all tissue specimens analysed. IL-11 is expressed predominantly during follicular and early luteal phase of the menstrual cycle. In IP, IL-11 expression peaks during the 1st trimester and declines from the beginning of the 2nd trimester onwards. In tubal abortions, IL-11 expression is reduced in comparison to vital EP and IP. Cultured primary endometrial and decidual epithelial cells were analysed for hormonal regulation of IL-11 by enzyme-linked immunosorbent assay and RT-PCR. IL-11 is up-regulated by estrogen and down-regulated by progesterone. Overall, our results indicate that in humans, IL-11 signalling is significantly involved in regulation of trophoblast invasion. In the case of tubal abortion, inadequate IL-11 signalling may therefore result in dysregulation of trophoblast invasion.