Decidual hemostasis, inflammation, and angiogenesis in pre-eclampsia

Association of urinary misfolded protein quantification with preeclampsia and adverse pregnancy outcomes: a retrospective case study

OBJECTIVES

This study aimed to explore the relationship between the detection of misfolded proteins in urine and preeclampsia (PE) as well as adverse pregnancy outcomes.

METHODS

A retrospective analysis was conducted on 400 pregnant women who underwent prenatal care at our hospital from January 2022 to May 2023. Demographic and clinical data were collected. The study documented the incidence of PE, positive urine misfolded protein detection rate, and the occurrence of adverse pregnancy outcomes. Factors influencing the occurrence of adverse pregnancy outcomes were also analyzed.

RESULTS

Out of the 400 pregnant women, 22 cases (5.50 %) developed PE. A total of 15 cases tested positive for misfolded proteins in urine, with 14 cases (63.64 %) of PE and 1 case (0.26 %) without PE. A history of smoking/secondhand smoke exposure (OR=3.592, 95 %CI: 3.217-4.012), oligohydramnios (OR=3.992, 95 %CI: 3.363-4.739), thyroid dysfunction (OR=2.164, 95 %CI: 1.835-2.552), the use of risky medications during pregnancy (OR=3.788, 95 %CI: 3.046-4.710), mild PE (OR=4.908, 95 %CI: 3.710-6.492), severe PE (OR=6.151, 95 %CI: 3.576-10.579), and a positive test for urinary misfolded proteins (OR=5.897, 95 %CI: 4.016-8.658) were all identified as risk factors for adverse pregnancy outcomes.

CONCLUSIONS

The rate of positive urinary misfolded protein detection was relatively high, but there was a certain rate of false positives. Furthermore, a positive test for urinary misfolded proteins and the severity of PE was associated with an increased incidence of adverse pregnancy outcomes.

Revealing the mechanism of fiber promoting sow embryo implantation by altering the abundance of uterine fluid proteins: A proteomic perspective

Many studies have shown that fiber in the diet plays an important role in improving the reproductive performance of sows, but there is rarely research on the impact of fiber on early embryo implantation. This study used 4D-Label free technology to identify and analyze the effect of the fiber composition in the diet on the protein in the early pregnancy uterine fluid (UF) of sows. The results indicate that ratio of insoluble fibers to soluble fibers (ISF/SF) 4.89 can increase the concentration of progesterone (PROG) and reduce tumor necrosis factorα (TNF-α) concentration in sow UF. In addition, through 4D-Label free, we identified a total of 4248 proteins, 38 proteins abundance upregulated and 283 proteins abundance downregulated in UF. Through enrichment analysis of these differential abundance proteins (DAPs), it was found that these differential proteins are mainly related to the docking of extracellular vesicles, vesicular transport, inflammatory response, and insulin resistance. Therefore, the results of this study reveal the possible mechanism by which fiber improves the reproductive performance of sows, laying a theoretical foundation for future research on the effects of diet on reproduction. SIGNIFICANCE: This study demonstrates the importance of dietary fiber for early embryo implantation in sows. The effect of dietary ISF/SF on early embryo implantation in sows was elucidated from a proteomic perspective through 4D-Label free technology. This study not only has significant implications for improving sow reproductive efficiency, but also provides important theoretical references for studying early miscarriage and reproductive nutrition in human pregnancy.

Three categories of similarities between the placenta and cancer that can aid cancer treatment: Cells, the microenvironment, and metabolites

Cancer is one of the most harmful diseases, while pregnancy is a common condition of females. Placenta is the most important organ for fetal growth, which has not been fully understand. It's well known that placenta and solid tumor have some similar biological behaviors. What's more, decidua, the microenvironment of placenta, and metabolism all undergo adaptive shift for healthy pregnancy. Interestingly, decidua and the tumor microenvironment (TME); metabolism changes during pregnancy and cancer cachexia all have underlying links. However, whether the close link between pregnancy and cancer can bring some new ideas to treat cancer is still unclear. So, in this review we note that pregnancy may offer clues to treat cancer related to three categories: from cell perspective, through the shared development process of the placenta and cancer; from microenvironment perspective, though the shared features of the decidua and TME; and from metabolism perspective, through shared metabolites changes during pregnancy and cancer cachexia. Firstly, comparing gene mutations of both placenta and cancer, which is the underlying mechanism of many similar biological behaviors, helps us understand the origin of cancer and find the key factors to restore tumorigenesis. Secondly, exploring how decidua affect placenta development and similarities of decidua and TME is helpful to reshape TME, then to inhibit cancer. Thirdly, we also illustrate the possibility that the altered metabolites during pregnancy may reverse cancer cachexia. So, some key molecules changed in circulation of pregnancy may help relieve cachexia and make survival with cancer realized.

Immature Platelet Fraction and Thrombin Generation: Preeclampsia Biomarkers

Preeclampsia, a human pregnancy syndrome, is characterized by elevated blood pressure and proteinuria after the 20th week of gestation. Its etiology remains unknown, and its pathophysiological mechanisms are related to placental hypoperfusion, endothelial dysfunction, inflammation, and coagulation cascade activation. Recently, the role of the complement system has been considered. This syndrome is one of the main causes of maternal and fetal mortality and morbidity. This article discusses the hypothesis of preeclampsia being triggered by the occurrence of inadequate implantation of the syncytiotrophoblast, associated with bleeding during the first stage of pregnancy and with augmented thrombin generation. Thrombin activates platelets, increasing the release of antiangiogenic factors and activating the complement system, inducing the membrane attack complex (C5b9). Immature platelet fraction and thrombin generation may be possible blood biomarkers to help the early diagnosis of preeclampsia.

Pathogenesis of uteroplacental acute atherosis: An update on current research

Uteroplacental acute atherosis is a type of arterial vascular disease that affects the placenta during pregnancy and predominates in the maternal spiral arteries in the decidua basalis layer of the pregnant uterus. This condition is characterized by fibrin-like necrosis of the blood vessel walls, the accumulation of macrophages containing fat (foam cells), and the infiltration of macrophages around blood vessels. Uteroplacental acute atherosis is rare in normal pregnancy but occurs more frequently in patients with pregnancy complications, including preeclampsia, spontaneous preterm labor, preterm prelabor rupture of membranes, mid-trimester spontaneous abortion, fetal death, and small-for-gestational age. It is believed that the mechanisms underlying the development of uteroplacental acute atherosis are related to the incomplete physiological transformation of spiral arteries, placental inflammation, abnormal lipid metabolism, and oxidative stress. In this review, we describe the pathogenesis of uteroplacental acute atherosis to provide reference guidelines for the future prevention and treatment of uteroplacental acute atherosclerotic disease.

Physiology of the Endometrium and Regulation of Menstruation

The physiological functions of the uterine endometrium (uterine lining) are preparation for implantation, maintenance of pregnancy if implantation occurs, and menstruation in the absence of pregnancy. The endometrium thus plays a pivotal role in reproduction and continuation of our species. Menstruation is a steroid-regulated event, and there are alternatives for a progesterone-primed endometrium, i.e., pregnancy or menstruation. Progesterone withdrawal is the trigger for menstruation. The menstruating endometrium is a physiological example of an injured or “wounded” surface that is required to rapidly repair each month. The physiological events of menstruation and endometrial repair provide an accessible in vivo human model of inflammation and tissue repair. Progress in our understanding of endometrial pathophysiology has been facilitated by modern cellular and molecular discovery tools, along with animal models of simulated menses. Abnormal uterine bleeding (AUB), including heavy menstrual bleeding (HMB), imposes a massive burden on society, affecting one in four women of reproductive age. Understanding structural and nonstructural causes underpinning AUB is essential to optimize and provide precision in patient management. This is facilitated by careful classification of causes of bleeding. We highlight the crucial need for understanding mechanisms underpinning menstruation and its aberrations. The endometrium is a prime target tissue for selective progesterone receptor modulators (SPRMs). This class of compounds has therapeutic potential for the clinical unmet need of HMB. SPRMs reduce menstrual bleeding by mechanisms still largely unknown. Human menstruation remains a taboo topic, and many questions concerning endometrial physiology that pertain to menstrual bleeding are yet to be answered.

Intrauterine Inflammation Damages Placental Angiogenesis via Wnt5a-Flt1 Activation

Intrauterine inflammation is the main reason for neonatal adverse outcomes and normal placenta perfusion plays an important role in fetal development. However, whether inflammation will affect placental angiogenesis and the underlying mechanism are still poorly understood. To investigate lipopolysaccharide (LPS)-induced intrauterine inflammation on placenta angiogenesis and Wnt5a-Flt1 expression. LPS-induced intrauterine inflammation rat model was established. Preterm rat outcomes were analyzed and angiogenesis of placenta villi was calculated by immunohistochemistry (IHC) of CD34 staining, and placenta Wnt5a-Flt1 expression was detected by western blot and IHC. Compared to control group, neonatal rats in LPS group showed higher death rate (1.4% vs 10.1%, p < 0.05) and lower birth weight (6.36 ± 0.48 vs 5.70 ± 0.67, p < 0.01); the villi vessel area and mean diameter in the placenta were significantly reduced in the LPS group (total area %, 16.7% ± 0.6% vs 8.7% ± 0.4%, p < 0.01, n = 9; mean diameter (pixel), 15.6 ± 0.5 vs 12.9 ± 0.3, p < 0.01, n = 9). Placenta Wnt5a-Flt1 expression was upregulated significantly (integrated optical density (IOD) in IHC: Wnt5a, 1667 ± 1204 vs 11,076 ± 4046, p < 0.05; Flt1, 2554 ± 466.2 vs 7998 ± 1613, p < 0.05; western blot: Wnt5a, 0.33 ± 0.05 vs 0.96 ± 0.06, p < 0.05; Flt1, 0.36 ± 0.15 vs 1.08 ± 0.08, p < 0.05). Intrauterine inflammation gave rise to offspring death rate and low birth weight; the mechanism might be disordered placental angiogenesis via Wnt5a-Flt1 activation triggered by inflammation.

Maternal Platelets—Friend or Foe of the Human Placenta?

Human pregnancy relies on hemochorial placentation, including implantation of the blastocyst and deep invasion of fetal trophoblast cells into maternal uterine blood vessels, enabling direct contact of maternal blood with placental villi. Hemochorial placentation requires fast and reliable hemostasis to guarantee survival of the mother, but also for the neonates. During human pregnancy, maternal platelet count decreases gradually from first, to second, and third trimester. In addition to hemodilution, accelerated platelet sequestration and consumption in the placental circulation may contribute to a decline of platelet count throughout gestation. Local stasis, turbulences, or damage of the syncytiotrophoblast layer can activate maternal platelets within the placental intervillous space and result in formation of fibrin-type fibrinoid. Perivillous fibrinoid is a regular constituent of the normal placenta which is considered to be an important regulator of intervillous hemodynamics, as well as having a role in shaping the developing villous trees. However, exaggerated activation of platelets at the maternal-fetal interface can provoke inflammasome activation in the placental trophoblast, and enhance formation of circulating platelet-monocyte aggregates, resulting in sterile inflammation of the placenta and a systemic inflammatory response in the mother. Hence, the degree of activation determines whether maternal platelets are a friend or foe of the human placenta. Exaggerated activation of maternal platelets can either directly cause or propagate the disease process in placenta-associated pregnancy pathologies, such as preeclampsia.

Macrophage Polarization in Physiological and Pathological Pregnancy

The immunology of pregnancy is complex and poorly defined. During the complex process of pregnancy, macrophages secrete many cytokines/chemokines and play pivotal roles in the maintenance of maternal-fetal tolerance. Here, we summarized the current knowledge of macrophage polarization and the mechanisms involved in physiological or pathological pregnancy processes, including miscarriage, preeclampsia, and preterm birth. Although current evidence provides a compelling argument that macrophages are important in pregnancy, our understanding of the roles and mechanisms of macrophages in pregnancy is still rudimentary. Since macrophages exhibit functional plasticity, they may be ideal targets for therapeutic manipulation during pathological pregnancy. Additional studies are needed to better define the functions and mechanisms of various macrophage subsets in both normal and pathological pregnancy.

IL-1 receptor antagonist therapy mitigates placental dysfunction and perinatal injury following Zika virus infection

Zika virus (ZIKV) infection during pregnancy causes significant adverse sequelae in the developing fetus, and results in long-term structural and neurologic defects. Most preventive and therapeutic efforts have focused on the development of vaccines, antivirals, and antibodies. The placental immunologic response to ZIKV, however, has been largely overlooked as a target for therapeutic intervention. The placental inflammatory response, specifically IL-1β secretion and signaling, is induced by ZIKV infection and represents an environmental factor that is known to increase the risk of perinatal developmental abnormalities. We show in a mouse model that maternally administrated IL-1 receptor antagonist (IRA; Kineret, or anakinra), following ZIKV exposure, can preserve placental function (by improving trophoblast invasion and placental vasculature), increase fetal viability, and reduce neurobehavioral deficits in the offspring. We further demonstrate that while ZIKV RNA is highly detectable in placentas, it is not correlated with fetal viability. Beyond its effects in the placenta, we show that IL-1 blockade may also directly decrease fetal neuroinflammation by mitigating fetal microglial activation in a dose-dependent manner. Our studies distinguish the role of placental inflammation during ZIKV-infected pregnancies, and demonstrate that maternal IRA may attenuate fetal neuroinflammation and improve perinatal outcomes.

Decidual cells from women with preeclampsia exhibit inadequate decidualization and reduced sFlt1 suppression

Uterine stromal cell decidualization of maternal tissue is essential for implantation of and local adaptation to the fetal allograft, as well as growth and maintenance of the placenta in healthy pregnancies. Maternal defects in decidualization have been suggested as a possible driver of preeclampsia. Preeclampsia (PE) pregnancies demonstrate shallow implantation, inadequate spiral artery remodeling, and elevated levels of the anti-angiogenic protein, sFlt1. To test whether stromal cells (DSCs) isolated from PE placentas exhibit inadequate re-decidualization and increased expression of sFlt1, DSCs from normotensive (NT-DSCs) and PE (PE-DSCs) placentas were treated for 8 days (D8) with cAMP to induce decidualization and levels of decidualization markers (PRL, IGFBP1, VEGF) and sFlt1 were measured at day 0 (D0), D8, and after reversal of treatment. NT-DSCs achieved statistically significant elevations in PRL and IFGBP1 expression (25.72 [5.78-50.04], p = 0.0008 and 92.09 [1.79-543.10], p = 0.005). PE-DSCs increased PRL and IFGBP1 expression to 6.15 [2.30-10.73] (p = 0.18) and 8.67 [1.64-376.10] (p = 0.04). NT-DSCs reduced sFlt1 expression at D8 to 0.25 [0.17-0.49] (p = 0.0021) compared to 0.31 [0.25-0.82] (p = 0.087) in PE-DSCs. These results show that, when induced to decidualize, PE-DSCs fail to increase expression of decidualization markers to levels achieved by NT-DSCs. sFlt1 expression is higher in PE-DSCs during decidualization, suggesting inadequate suppression during the crucial implantation period. These defects at the maternal fetal interface may lead to the failed spiral artery modification, decreased placental invasion of the uterus, and elevated circulating sFlt1 levels seen in PE pathology.

Int6/eIF3e Silencing Promotes Placenta Angiogenesis in a Rat Model of Pre-eclampsia

We investigated whether stable eukaryotic translation initiation factor 3e/inter 6 (eIF-3e/Int6) RNA-silencing (siRNA-Int6) can ameliorate pre-eclampsia (PE) by promoting angiogenesis in an N-nitro-L-arginine methyl ester (L-NAME)-induced rat pre-eclampsia (PE) model. Twenty-four pregnant female Sprague–Dawley rats were allocated into 4 groups, including controls (Con) without any treatment, and 18 from gestational day (GD) 7 to GD17 L-NAME-treated rats, which were divided into stable siRNA-Int6 transfected (siRNA-Int6), negative vector control siRNA (NC-siRNA) and PE control (PE-Con) groups. All adenovirus siRNA transfections were performed on GD7 via intravenous tail injection. On GD0, GD11 and GD17, blood pressure, and on GD6 and GD17, protein estimations in 24 h urine samples were conducted. All animals were sacrificed on GD18. In the PE-Con group, placental Int6 was expressed to a significantly greater level than in the Con group, which was reversed by the application of siRNA-Int6. Blood pressure and proteinuria were significantly lower in the siRNA-Int6 group than in the PRE-Con group. As shown by CD31 and IB4 expression, placental micro-vascular density (MVD) was significantly higher in the siRNA-Int6 group than in the PE-Con and NC-siRNA groups, which has accompanied by enhanced trophoblast invasion. Int6 silencing alleviated the maternal clinical manifestations of pre-eclampsia and promoted placental angiogenesis in pregnant L-NAME-treated rats.

Effects of excess thromboxane A2 on placental development and nutrient transporters in a Mus musculus model of fetal growth restriction

Hypertensive disease of pregnancy (HDP) with placental insufficiency is the most common cause of fetal growth restriction (FGR) in the developed world. Despite the known negative consequences of HDP both to the mother and fetus, little is known about the longitudinal placental changes that occur as HDP progresses in pregnancy. This is because longitudinal sampling of human placentae during each gestation is impossible. Therefore, using a mouse model of thromboxane A2-analog infusion to mimic human HDP in the last trimester, we calculated placental efficiencies based on fetal and placental weights; quantified spongiotrophoblast and labyrinth thicknesses and vascular density within these layers; examined whether hypoxia signaling pathway involving vascular endothelial growth factor A (VEGFA) and its receptors (VEGFR1, VEGFR2) and matrix metalloproteinases (MMPs) contributed to vascular change; and examined nutrient transporter abundance including glucose transporters 1 and 3 (GLUT1, GLUT3), neutral amino acid transporters 1, 2, and 4 (SNAT1, SNAT2, and SNAT4), fatty acid transporters 2 and 4 (FATP2, FATP4), and fatty acid translocase (CD36) from embryonic day 15.5 to 19 in a 20-day C57Bl/6J mouse gestation. We conclude that early-to-mid gestation hypertensive placentae show compensatory mechanisms to preserve fetal growth by increasing placental efficiencies and maintaining abundance of important nutrient transporters. As placental vascular network diminishes over late hypertension, placental efficiency diminishes and fetal growth fails. Neither hypoxia signaling pathway nor MMPs mediated the vascular diminution in this model. Hypertensive placentae surprisingly exhibit a sex-differential expression of nutrient transporters in late gestation despite showing fetal growth failure in both sexes.

Thrombin Alters Human Endometrial Stromal Cell Differentiation During Decidualization

Vaginal bleeding and subchorionic hematomas are associated with increased risk of both early and late pregnancy loss. Thrombin generation may play a pivotal role in the development of these complications. To determine the effects of thrombin on human endometrial stromal cells (hESCs), cells were treated with thrombin at baseline or during decidualization with cyclic adenosine monophosphate (cAMP)+medroxyprogesterone acetate (MPA). Next-generation RNA sequencing revealed that markers of decidualization (IGF-1, IGFBP-1, and prolactin [PRL]) were induced after the initiation of decidualization, whereas thrombin suppressed insulin-like growth factor ( IGF)-1, Insulin-like growth factor binding protein ( IGFBP)-1, and PRL gene expression at baseline and during decidualization. These effects were mediated through protease activated receptor (PAR)-1- and PAR-1-independent pathways. Thrombin decreased the secretion of a key marker of decidualization (PRL), altered the morphological transformation of decidualizing hESCs, and activated genes involved in matrix degradation and proinflammatory chemokines ( Interleukin-8 and Interleukin-6). Genes encoding factors important for matrix stability ( Col1α1, LOX) were suppressed. We suggest that intrauterine bleeding and generation of thrombin accentuates leukocyte extravasation and endometrial inflammation, impairs decidualization, and endometrial support of early pregnancy.

Toll-like 4 receptor /NFκB inflammatory/miR-146a pathway contributes to the ART-correlated preterm birth outcome

Assisted reproductive technology (ART) is widely used for the women with infertility conditions to achieve pregnancy. However, the adverse effects of ART may lead to poor perinatal and neonatal outcomes, e.g., preterm birth and low body weight. In this study, we investigated the inflammatory molecular factors and microRNA that might be involved in ART related preterm birth. We found the elevation of Toll-like 4 receptor (TLR4), activation of NFκB pathway and down-regulation of microRNA-146a (miR-146a), a negative regulator of NFκB, in the placenta of preterm birth and ART, indicating preterm birth and ART were associated with inflammation signaling activation. In vitro experiments demonstrated that miR-146a suppressed NFκB pathway and shifted the balance of cytokines in the cord blood toward a repertoire of pro-inflammatory outcomes by down-regulating IRAK1 and TRAF6. The pro-inflammatory cytokines IL-6, IFNγ and TNFα in the cord blood were highly expressed in the preterm and ART, while anti-inflammatory cytokine IL-10 was the lower in the preterm and ART. In summary, we firstly uncovered that TLR4/NFκB mediated inflammation signaling and miR-146a participated in ART-related preterm birth patients, which suggests that importance of TLR4/NFκB/miR-146a signaling in clinical interventions and biomarkers of ART-related perinatal or neonatal outcomes.

hCG: Biological Functions and Clinical Applications

Human chorionic gonadotropin (hCG) is produced primarily by differentiated syncytiotrophoblasts, and represents a key embryonic signal that is essential for the maintenance of pregnancy. hCG can activate various signaling cascades including mothers against decapentaplegic homolog 2 (Smad2), protein kinase C (PKC), and/or protein kinase A (PKA) in several cells types by binding to luteinizing hormone/chorionic gonadotropin receptor (LHCGR) or potentially by direct/indirect interaction with transforming growth factor beta receptor (TGFβR). The molecule displays specialized roles in promoting angiogenesis in the uterine endothelium, maintaining myometrial quiescence, as well as fostering immunomodulation at the maternal-fetal interface. It is a member of the glycoprotein hormone family that includes luteinizing hormone (LH), thyroid-stimulating hormone (TSH), and follicle-stimulating hormone (FSH). The α-subunit of hCG displays homologies with TSH, LH, and FSH, whereas the β subunit is 80–85% homologous to LH. The hCG molecule is produced by a variety of organs, exists in various forms, exerts vital biological functions, and has various clinical roles ranging from diagnosis and monitoring of pregnancy and pregnancy-related disorders to cancer surveillance. This review presents a detailed examination of hCG and its various clinical applications.

Impact of haemostatic mechanisms on pathophysiology of preeclampsia

Preeclampsia (PE) is disorder of new onset hypertension and proteinuria during the second half of pregnancy. There is increasing evidence to implicate placental over-expression of tissue factor and PAR-1 in the pathophysiology of PE. Excessive activation of platelets, neutrophils and the complement system may also contribute to the placental pathology and maternal endothelial responsible for the symptoms of PE. Increased knowledge in this field may identify new therapeutic strategies for the treatment of PE.

Expression and regulation of 11β-hydroxysteroid dehydrogenase type 1 in first trimester human decidua cells: Implication in preeclampsia

Glucocorticoids are implicated in successful blastocyst implantation, whereas alterations in glucocorticoid levels are associated with various pregnancy disorders including preeclampsia. Tissue concentration of active glucocorticoids depends on the expression of 11β-hydroxysteroid dehydrogenase (11β-HSD). This study investigated the contribution of first trimester decidua to glucocorticoid availability at the fetal-maternal interface by assessing the expression and regulation of 11β-HSD in human first trimester decidual tissues and cells and by evaluating 11β-HSD levels in preeclamptic vs. gestational age-matched decidua. 11β-HSD1 was the predominant isoform in first trimester decidua. In vitro, decidual cell 11β-HSD1 levels and enzymatic activity were up-regulated by ovarian steroids and inflammatory cytokines. Higher levels of 11β-HSD1 were found in preeclamptic decidua compared to controls. The present study indicates the predominance of 11β-HSD oxoreductase isoform in early decidua. Observations that ovarian hormones and inflammatory cytokines up-regulate 11β-HSD1, together with increased 11β-HSD1 expression in preeclampsia, highlight a role for decidual cells in controlling biologically active glucocorticoids in early pregnancy.

Calcitonin Gene-Related Peptide Rescues Proximity Associations of Its Receptor Components, Calcitonin Receptor-Like Receptor and Receptor Activity-Modifying Protein 1, in Rat Uterine Artery Smooth Muscle Cells Exposed to Tumor Necrosis Factor Alpha

Calcitonin gene-related peptide (CALCB), adrenomedullin (ADM), and ADM2/intermedin play critical roles in vascular adaptation during pregnancy through calcitonin receptor-like receptor (CALCRL) and receptor activity-modifying proteins (RAMPs). This study was designed to assess the predominant RAMP that associates with CALCRL to form a functional receptor in the rat uterine artery smooth muscle (RUASM). We also determined if these receptor component associations are decreased by tumor necrosis factor (TNF) alpha and if CALCB, ADM, or ADM2 can rescue CALCRL/RAMP associations. Using proximity ligation assay in RUASM cells, this study shows that CALCRL predominantly associates with RAMP1 forming a CALCB receptor, and minimally with RAMP2 and RAMP3 that confer specificity for ADM and ADM2. However, knockdown of RAMP1 mRNA increases the interaction between CALCRL and RAMP3 without affecting the association of CALCRL and RAMP2. Furthermore, CALCB, ADM, and ADM2 have no effects on the associations of CALCRL with any of the RAMPs in RUASM cells. Interestingly, CALCB reverses the TNFalpha-induced decreases in CALCRL/RAMP1 associations. Furthermore, CALCB increases ERK1/2 phosphorylation in a time-dependent manner in RUASM, and the protective effect of CALCB on TNFalpha-induced inhibition of CALCRL/RAMP1 associations was significantly blocked in presence of ERK inhibitor (PD98059). In conclusion, this study demonstrates that CALCRL predominantly associates with RAMP1 forming a CALCB-specific receptor complex in RUASM cells, which is dissociated by TNFalpha. Rescue of TNFalpha-induced dissociation of CALCRL/RAMP1 complex by CALCB in RUASM cells suggests a potential use of CALCB in developing therapeutic strategies for pregnancy-related complications that are vulnerable to abnormal levels of TNFalpha, such as fetal growth restriction and preeclampsia.

Stillbirth, hypertensive disorders of pregnancy, and placental pathology

INTRODUCTION

Stillbirth, preeclampsia, and gestational hypertension (PE/GH) have similar clinical risk factors and redundant placental pathology. We aim to discern if stillbirth with PE/GH has a particular phenotype by comparing stillbirths with and without PE/GH.

METHODS

Secondary analysis of the Stillbirth Collaborative Research Network, a population-based cohort study of all stillbirths and a sample of live births from 2006 to 2008 in five catchment areas. We compared placental pathology between stillbirths and with and without PE/GH, stratified by term or preterm. We also compared placental pathology between stillbirths and live births with PE/GH.

RESULTS

79/518 stillbirths and 140/1200 live births had PE/GH. Amongst preterm stillbirths, there was higher feto-placental ratio in PE/GH pregnancies (OR 1.24 [1.11, 1.37] per unit increase), and there were more parenchymal infarctions (OR 5.77 [3.18, 10.47]). Among PE/GH pregnancies, stillbirths had increased maternal and fetal vascular lesions, including retroplacental hematoma, parenchymal infarction, fibrin deposition, fetal vascular thrombi, and avascular villi.

DISCUSSION

Stillbirth pregnancies are overwhelmingly associated with placental lesions. Parenchymal infarctions are more common in PE/GH preterm stillbirths, but there is significant overlap in lesions found in stillbirths and PE/GH.

Morphological changes of placental syncytium and their implications for the pathogenesis of preeclampsia

Preeclampsia is a hypertensive disease that complicates many pregnancies, typically presenting with new-onset or worsening hypertension and proteinuria. It is well recognized that the placental syncytium plays a key role in the pathogenesis of preeclampsia. This review summarizes the findings pertaining to the structural alterations in the syncytium of preeclamptic placentas and analyzes their pathological implications for the development of preeclampsia. Changes in the trophoblastic lineage, including those in the proliferation of cytotrophoblasts, the formation of syncytiotrophoblast through cell fusion, cell apoptosis and syncytial deportation, are discussed in the context of preeclampsia. Extensive correlations are made between functional deficiencies and the alterations on the levels of gross anatomy, tissue histology, cellular events, ultrastructure, molecular pathways, and gene expression. Attention is given to the significance of dynamic changes in the syncytial turnover in preeclamptic placentas. Specifically, experimental evidences for the complex and obligatory role of syncytin-1 in cell fusion, cell-cycle regulation at the G1/S transition, and apoptosis through AIF-mediated pathway, are discussed in detail in the context of syncytium homeostasis. Finally, the recent observations on the aberrant fibrin deposition in the trophoblastic layer and the trophoblast immature phenotype in preeclamptic placentas and their potential pathogenic impact are also reviewed.

Infertility and reproductive disorders: impact of hormonal and inflammatory mechanisms on pregnancy outcome

BACKGROUND

Reproductive disorders and infertility are associated with the risk of obstetric complications and have a negative impact on pregnancy outcome. Affected patients often require assisted reproductive technologies (ART) to conceive, and advanced maternal age is a further confounding factor. The challenge is to dissect causation, correlation and confounders in determining how infertility and reproductive disorders individually or together predispose women to poor pregnancy outcomes.

METHODS

The published literature, to June 2015, was searched using PubMed, summarizing all evidences concerning the perinatal outcome of women with infertility and reproductive disorders and the potential mechanisms that may influence poor pregnancy outcome.

RESULTS

Reproductive disorders (endometriosis, adenomyosis, polycystic ovary syndrome and uterine fibroids) and unexplained infertility share inflammatory pathways, hormonal aberrations, decidual senescence and vascular abnormalities that may impair pregnancy success through common mechanisms. Either in combination or alone, these disorders results in an increased risk of preterm birth, fetal growth restriction, placental pathologies and hypertensive disorders. Systemic hormonal aberrations, and inflammatory and metabolic factors acting on endometrium, myometrium, cervix and placenta are all associated with an aberrant milieu during implantation and pregnancy, thus contributing to the genesis of obstetric complications. Some of these features have been also described in placentas from ART.

CONCLUSIONS

Reproductive disorders are common in women of childbearing age and rarely occur in isolation. Inflammatory, endocrine and metabolic mechanisms associated with these disorders are responsible for an increased incidence of obstetric complications. These patients should be recognized as 'high risk' for poor pregnancy outcomes and monitored with specialized follow-up. There is a real need for development of evidence-based recommendations about clinical management and specific obstetric care pathways for the introduction of prompt preventative care measures.

Changes in Functional Activity of JEG-3 Trophoblast Cell Line in the Presence of Factors Secreted by Placenta

BACKGROUND AND AIMS

Cells in the maternal-fetal interface secrete cytokines that regulate proliferation, migration, and trophoblast invasion during the first trimester of pregnancy and the limitation of these processes during the third trimester. The aim of the study was to evaluate the influence of factors secreted by human placenta during the first and third trimester of pregnancy on cytokine receptor expression and proliferative and migratory activity of JEG-3 trophoblast cells.

METHODS

The research was conducted using the explant conditioned media of placentas obtained from healthy women with elective termination of pregnancy at 9-11 weeks and placentas of women whose pregnancy progressed without complications at 38-39 weeks. Assessment of surface molecule expression was performed using FACS Canto II flow cytometer (BD, USA). The proliferative activity of JEG-3 trophoblast cells was evaluated by dyeing with crystal violet vital dye. The migration activity of JEG-3 was evaluated using 24-well insert plates with polycarbonate inserts (pore size 8 microns).

RESULTS

Expression of CD116, CD118, CD119, IFNγ-R2, CD120b, CD183, CD192, CD295, EGFR, and TGFβ-R2 on JEG-3 was higher when the cells were incubated in the presence of the third trimester placental factors in comparison with the first trimester placental factors. Factors secreted by the placenta during the third trimester of pregnancy had more pronounced stimulatory effect on the proliferation and migration of trophoblast in comparison with baseline levels and with the effect of the first trimester placental factors.

CONCLUSIONS

The findings suggest that the behavior of trophoblasts in vitro might not be representative of in vivo behavior in the absence of additional local factors that influence the trophoblast in vivo.

Pathophysiological basis for compromised health beyond generations: role of maternal high-fat diet and low-grade chronic inflammation

Early exposure to a fat-enriched diet programs the developmental profile and thus is associated with disease susceptibility in subsequent generations. Chronic low-grade inflammation, resulting from maternal high-fat diet, is activated in the fetal environment and in many organs of offspring, including placenta, adipose, liver, vascular system and brain. The prevalence of an inflammatory response is highly associated with obesity incidence, cardiovascular diseases, nonalcoholic fatty liver disease and brain damage. Substantial studies using high-fat model have consistently demonstrated the incidence of such inflammatory reactions; however, the potential contribution of active inflammation toward the physiological outcomes and developmental diseases is neither discussed in depth nor systemically integrated. Therefore, we aim to summarize the current findings in regards to how a maternal high-fat diet influences the inflammatory status, and probable pathogenic effects on the offspring. More importantly, since limited research has been conducted to reveal the epigenetic regulation of these inflammatory markers by maternal high-fat diet, we sincerely hope that our review will not only outline the pathophysiological relevance of inflammation but also identify a future direction for mechanistic investigation and clinical application.

Comparative incidence of pregnancy outcomes in thrombophilia-positive women from the NOH-APS observational study

Fetal death is more frequent in women with prior abortions carrying F5 rs6025 or F2 rs1799963 polymorphisms vs nonthrombophilic women. Pregnancy complications are less frequent in LMWH-treated thrombophilic women with fetal loss vs untreated nonthrombophilic women.

Advanced oxidation protein products enhances soluble Fms-like tyrosine kinase 1 expression in trophoblasts: a possible link between oxidative stress and preeclampsia

Accumulation of advanced oxidation protein products (AOPPs) is prevalent in obesity, advanced maternal age, diabetes mellitus, and polycystic ovary syndrome. Alterations in the regulation and signaling of angiogenic pathways have been recognized as a link between these conditions and pre-eclampsia. To investigate the possible impact of AOPPs on soluble Fms-like tyrosine kinase 1 (sFlt-1) expression in trophoblasts. A trophoblast cell line (HRT-8/SVneo) was treated with various concentrations of AOPPs. The mRNA expression of sFlt-1, vascular endothelial growth factor (VEGF), and placental growth factor (PlGF) in trophoblasts were measured with the use of real-time polymerase chain reaction; and the secretion of sFlt-1, VEGF, and PlGF protein from trophoblasts were detected with the use of ELISA. Exposure of HRT-8/SVneo cells to AOPPs induced overexpression of sFlt-1 at mRNA and protein levels in a dose dependent manner. These effects could be inhibited by apocynin, an inhibitors of NADPH oxidase. Our data identified AOPPs as a class of important mediator in the regulation and signaling of angiogenic pathways of trophoblasts. Accumulation of AOPPs might contributes to the pathogenesis of preeclampsia by promoting sFlt-1 production in trophoblasts.

Improvement of insulin sensitivity promotes extravillous trophoblast cell migration stimulated by insulin-like growth factor-I

Insulin-like growth factor-I (IGF-I) has been shown to stimulate extravillous trophoblast (EVT) cell migration and invasion, and to play a crucial role in placental function, thereby, influencing placental development and fetal growth. Insufficient invasion of EVT cells into the uterine endometrium leads to pregnancy-related complications, including spontaneous abortion, fetal growth restriction (FGR), and pregnancy-induced hypertension (PIH). Insulin-resistant conditions such as polycystic ovary syndrome (PCOS) and gestational diabetes mellitus (GDM) have also been associated with abortion and PIH. However, the effects of IGF-I on EVT cells under insulin-resistant conditions have not been elucidated yet. The current study was undertaken to analyze the effects of IGF-I under insulin-resistant conditions and to determine whether improvement in insulin sensitivity alters IGF signaling and cell migration in the EVT. Incubation with pioglitazone, an insulin sensitizer, increased peroxisome proliferator-activated receptor-γ (PPARγ) expression after 48 h. A 48-h pre-incubation with insulin reduced the phosphorylation and concentration of the insulin receptors, which were increased by insulin treatment. Long-term exposure to insulin reduced phosphorylation of the IGF-I receptor, insulin receptor substrate-1 (IRS-1), and Akt, and also reduced EVT cell migration. However, when the cells were incubated with pioglitazone in addition to insulin for 48 h, the phosphorylation of these proteins was restored. This combination partially reversed the inhibitory effect of insulin on EVT cell migration. These results suggest that abnormalities in pregnancy that are induced by loss of insulin sensitivity can be treated by improving insulin sensitivity.

miR-16 inhibits the proliferation and angiogenesis-regulating potential of mesenchymal stem cells in severe pre-eclampsia

Pre-eclampsia is thought to be a systemic disease of maternal endothelial cell dysfunctions. miRNAs regulate various basic biological functions in cells, including stem cells. Mesenchymal stem cells exist in almost all tissues and are the key cellular source for tissue repair and regeneration. Our aims are to investigate whether miRNAs regulate MSCs in fetal-maternal interfaces to influence the pathogenesis of pre-eclampsia. The differential expression of miRNAs in decidua-derived mesenchymal stem cells of all patients with severe pre-eclampsia (n = 20) and normal groups (n = 20) was first screened by microarray analysis and validated by quantitative real-time PCR analysis. The integrated bioinformatics analysis showed that miR-16 showed the highest number of connections in the miRNA GO network and the miRNA gene network. Moreover, over-expressed miR-16 inhibited the proliferation and migration of decidua-derived mesenchymal stem cells and induced cell-cycle arrest by targeting cyclin E1. Interestingly, over-expression of miR-16 by decidua-derived mesenchymal stem cells reduced the ability of human umbilical vein endothelial cells to form blood vessels and reduced the migration of trophoblast cells. Furthermore, decidua-derived mesenchymal stem cell-expressed endothelial growth factor VEGF-A was involved in migration of trophoblast cells and human umbilical vein endothelial cells as well as tube and network formation. Importantly, the levels of cyclin E1 and VEGF-A were negatively correlated with the level of miR-16 expression in decidua-derived mesenchymal stem cells from the patients with severe pre-eclampsia. Together, these data suggest that the alteration of miR-16 expression in decidua-derived mesenchymal stem cells may be involved in the development of pre-eclampsia.

Decreased expression of complement 3a receptor (C3aR) in human placentas from severe preeclamptic pregnancies

OBJECTIVES

The aim of this study was to determine the expression of the anaphylatoxin receptors complement C3a receptor (C3aR) and C5a receptor (C5aR) in the placentas of pregnancies complicated by severe early onset preeclampsia.

STUDY DESIGN

We recruited women with pregnancies complicated by severe early-onset preeclampsia (n=19, 11 of which were further complicated with IUGR) and women with preterm pregnancies not affected by preeclampsia (n=8). Gene and protein expression of C3aR and C5aR was analysed by quantitative RT-PCR and Western blotting, respectively.

RESULTS

C3aR was detected in the Hofbauer cells in the villous stroma of the placenta. C5aR staining was detected in the syncytiotrophoblast and endothelial cells. We found significantly decreased expression of C3aR mRNA and protein expression in placentas with preeclampsia compared to controls. However, C5aR expression was not significantly different between preeclamptic and control placentas at either the mRNA or protein level.

CONCLUSIONS

Decreased C3aR expression indicates a dysregulation of the complement system in the placentas of preeclamptic women. Further studies would elucidate the exact mechanisms that complement has in preeclampsia.

A genome-wide approach reveals novel imprinted genes expressed in the human placenta

Genomic imprinting characterizes genes with a monoallelic expression, which is dependent on the parental origin of each allele. Approximately 150 imprinted genes are known to date, in humans and mice but, though computational searches have tried to extract intrinsic characteristics of these genes to identify new ones, the existing list is probably far from being comprehensive. We used a high-throughput strategy by diverting the classical use of genotyping microarrays to compare the genotypes of mRNA/cDNA vs. genomic DNA to identify new genes presenting monoallelic expression, starting from human placental material. After filtering of data, we obtained a list of 1,082 putative candidate monoallelic SNPs located in more than one hundred candidate genes. Among these, we found known imprinted genes, such as IPW, GRB10, INPP5F and ZNF597, which contribute to validate the approach. We also explored some likely candidates of our list and identified seven new imprinted genes, including ZFAT, ZFAT-AS1, GLIS3, NTM, MAGI2, ZC3H12Cand LIN28B, four of which encode zinc finger transcription factors. They are, however, not imprinted in the mouse placenta, except for Magi2. We analyzed in more details the ZFAT gene, which is paternally expressed in the placenta (as ZFAT-AS1, a non-coding antisense RNA) but biallelic in other tissues. The ZFAT protein is expressed in endothelial cells, as well as in syncytiotrophoblasts. The expression of this gene is, moreover, downregulated in placentas from complicated pregnancies. With this work we increase by about 10% the number of known imprinted genes in humans.

Innate immunity, decidual cells, and preeclampsia

Preeclampsia (PE) manifested by hypertension and proteinuria complicates 3% to 8% of pregnancies and is a leading cause of fetal-maternal morbidity and mortality worldwide. It may lead to intrauterine growth restriction, preterm delivery, and long-term sequelae in women and fetuses, and consequently cause socioeconomic burden to the affected families and society as a whole. Balanced immune responses are required for the maintenance of successful pregnancy. Although not a focus of most studies, decidual cells, the major resident cell type at the fetal-maternal interface, have been shown to modulate the local immune balance by interacting with other cell types, such as bone marrow derived-immune cells, endothelial cells, and invading extravillous trophoblasts. Accumulating evidence suggests that an imbalanced innate immunity, facilitated by decidual cells, plays an important role in the pathogenesis of PE. Thus, this review will discuss the role of innate immunity and the potential contribution of decidual cells in the pathogenesis of PE.

The role of interleukin-1β in human trophoblast motility

The pleiotropic cytokine interleukin-1β (IL-1β) can promote physiological cell migration, as well as cancer cell invasion and metastasis. Its role in human trophoblast invasion, however, has not been satisfactorily answered since direct, indirect as well as no effects on trophoblast motility have been published. Therefore, the role of IL-1β has been re-evaluated by exclusively using human primary trophoblast model systems. Immunofluorescence of first trimester placentae indicated IL-1 receptor 1 (IL-1R1) protein expression in first trimester villous cytotrophoblasts (vCTB) and extravillous trophoblasts (EVT). The latter expressed higher mRNA levels of the receptor as shown by comparative gene chip data of vCTB and EVT. Similarly, Western blot analyses and immunofluorescence revealed a time- and differentiation-dependent increase of IL-1R1 in primary EVT seeded on fibronectin. IL-1β dose-dependently elevated migration of isolated first trimester EVT through fibronectin-coated transwells, which was inhibited in the presence of IL-1R antagonist (IL-1Ra), whereas proliferation of these cells was not affected. Similarly, the interleukin did not alter proliferation of vCTB and cell column trophoblasts in floating villi of early pregnancy, but promoted migration in villous explant cultures seeded on collagen I. Western blot analyses of supernatants of primary EVT and first trimester villous explant cultures revealed IL-1β induced secretion of urokinase plasminogen activator (uPA), plasminogen activator inhibitor (PAI)-1 and PAI-2, which was diminished upon combined IL-1β/IL-1Ra treatment. In conclusion, these data suggest that IL-1β directly promotes trophoblast motility of first trimester EVT involving the uPA/PAI system.

Key cellular components and interactive histocompatibility molecules regulating tolerance to the fetal allograft

Implantation is a major landmark in life. It involves the correct apposition of the embryo in the maternal endometrium. The cellular environment influences placenta development, and direct contact of the fetus with maternal tissues is achieved through decidual cells. At the decidua, and at systemic level, the correct balance of cells potentially acting as antigen-presenting cells and histocompatibility products play a pivotal role in achieving feto-maternal tolerance. Here, we review some of the current issues associated with the interplay between cells and molecules needed for pregnancy development.

Preeclampsia, hypoxia, thrombosis, and inflammation

Reductions in uteroplacental flow initiate a cascade of molecular effects leading to hypoxia, thrombosis, inflammation, and endothelial cell dysfunction resulting in untoward pregnancy outcomes. In this review, we detail these effects and their relationship to preeclampsia (PE) and intrauterine growth restriction (IUGR).

Is heparin a placental anticoagulant in high-risk pregnancies?

Randomized control trials show beneficial effects of heparin in high-risk pregnancies to prevent preeclampsia and intrauterine growth restriction. However, the lack of placental pathology data in these trials challenges the assumption that heparin is a placental anticoagulant. Recent data show that placental infarction is probably associated with abnormalities in development of the placenta, characterized by poor maternal perfusion and an abnormal villous trophoblast compartment in contact with maternal blood, than with maternal thrombophilia. At-risk pregnancies may therefore be predicted by noninvasive prenatal testing of placental function in mid-pregnancy. Heparin has diverse cellular functions that include direct actions on the trophoblast. Dissecting the non-anticoagulant actions of heparin may indicate novel and safer therapeutic targets to prevent the major placental complications of pregnancy.

Vesicular stomatitis virus has extensive oncolytic activity against human sarcomas: rare resistance is overcome by blocking interferon pathways

Oncolytic viruses have been tested against many carcinomas of ectodermal and endodermal origin; however, sarcomas, arising from mesoderm, have received relatively little attention. Using 13 human sarcomas representing seven tumor types, we assessed the efficiency of infection, cytolysis, and replication of green fluorescent protein (GFP)-expressing vesicular stomatitis virus (VSV) and its oncolytically enhanced mutant VSV-rp30a. Both viruses efficiently infected and killed 12 of 13 sarcomas. VSV-rp30a showed a faster rate of infection and replication. In vitro and in vivo, VSV was selective for sarcomas compared with normal mesoderm. A single intravenous injection of VSV-rp30a selectively infected all subcutaneous human sarcomas tested in mice and arrested the growth of tumors that otherwise grew 11-fold. In contrast to other sarcomas, synovial sarcoma SW982 demonstrated remarkable resistance, even to high titers of virus (multiplicity of infection [MOI] of 100). We found no dysfunction in VSV binding or internalization. SW982 also resisted infection by human cytomegalovirus and Sindbis virus, suggesting a virus resistance mechanism based on an altered antiviral state. Quantitative reverse transcriptase (qRT)-PCR analysis revealed a heightened basal expression of interferon-stimulated genes (ISGs). Pretreatment, but not cotreatment, with interferon attenuators valproate, Jak1 inhibitor, or vaccinia virus B18R protein rendered SW982 highly susceptible, and this correlated with downregulation of ISG expression. Jak1 inhibitor pretreatment also enhanced susceptibility in moderately VSV-resistant liposarcoma and bladder carcinoma. Overall, we find that the potential efficacy of VSV as an oncolytic agent extends to nonhematologic mesodermal tumors and that unusually strong resistance to VSV oncolysis can be overcome with interferon attenuators.