Trophoblast Giant Cells Research Articles

FARE GEBELİK DÖNEMİNDE HAREKETSİZLİK STRESİNİN PLASENTA VE YAVRUYA ETKİLERİ

ABSTRACT AIM: Stress can affect negatively mother and fetuses during pregnancy. We aimed to investigate the effects of chronic immobilization stress on placental maturation and fetal development.MATERİALS AND METHODS: Balb/c virgin female mice (20-30 g) were mated with male mice in a 2 to 1 female to male ratio. Pregnant mice in control group (n=6) were left undisturbed, whereas pregnant mice in the stress group (n=6) were exposed to 45 min chronic immobilization stress for three times/day starting from gestational day 6 till 18. Fetuses and placentas were removed from dams on the gestational day 18 under anesthesia.RESULTS: The prenatal stress significantly increased apoptosis in several placental cells including trophoblastic giant cells, glycogen cells and labyrinth trophoblastic cells and resulted in intrauterine growth restriction. The stress caused a decreased superoxide dismutase and glutathione levels. Alizarin Red S staining shows the ossification center of the fetuses to see developmental abnormality. CONCLUSION: Gestational stress causes placental dysfunctions by triggering apoptosis, reducing the labyrinth zone as well as increasing collagen levels, which may impair fetal development that may contribute to pathogenesis of intrauterine growth restriction.

The Immunology of Syncytialized Trophoblast.

Multinucleate syncytialized trophoblast is found in three forms in the human placenta. In the earliest stages of pregnancy, it is seen at the invasive leading edge of the implanting embryo and has been called primitive trophoblast. In later pregnancy, it is represented by the immense, multinucleated layer covering the surface of placental villi and by the trophoblast giant cells found deep within the uterine decidua and myometrium. These syncytia interact with local and/or systemic maternal immune effector cells in a fine balance that allows for invasion and persistence of allogeneic cells in a mother who must retain immunocompetence for 40 weeks of pregnancy. Maternal immune interactions with syncytialized trophoblast require tightly regulated mechanisms that may differ depending on the location of fetal cells and their invasiveness, the nature of the surrounding immune effector cells and the gestational age of the pregnancy. Some specifically reflect the unique mechanisms involved in trophoblast cell–cell fusion (aka syncytialization). Here we will review and summarize several of the mechanisms that support healthy maternal–fetal immune interactions specifically at syncytiotrophoblast interfaces.

The BMP2 Signaling Axis Promotes Invasive Differentiation of Human Trophoblasts.

Embryo implantation and trophoblast invasion are principal limiting factors of pregnancy establishment. Aberrant embryo development or improper trophoblast differentiation and invasion may lead to various unfavorable pregnancy-related outcomes, including early pregnancy loss (EPL). Our clinical data show that the serum BMP2 levels were significantly increased during the first trimester of pregnancy and that the serum and BMP2 expression levels were lower in women with EPL than in women with normal early pregnancies. Moreover, we observed that BMP2 was expressed in oocytes and trophoblast cells of cleaved embryos and blastocysts prior to implantation in both humans and mice. Exogenous BMP2 promoted embryonic development by enhancing blastocyst formation and hatching in mice. LncRNA NR026833.1 was upregulated by BMP2 and promoted SNAIL expression by competitively binding to miR-502-5p. SNAIL induced MMP2 expression and promoted cell invasion in primary extravillous trophoblast cells. BMP2 promotes the invasive differentiation of mouse trophoblast stem cells by downregulating the expression of TS cell marker and upregulating the expression of trophoblast giant cell marker and labyrinthine/spongiotrophoblast marker. Our findings provide significant insights into the regulatory roles of BMP2 in the development of the placenta, which may give us a framework to explore new therapeutic strategies to pregnancy-related complications.

937 Adrenomedullin regulates trophoblast invasion at the uterine-placental interface and is critical for successful pregnancy

Background: Adrenomedullin (ADM) is a vasoactive peptide hormone found in adrenal medulla, central nervous system, immune cells, and muscle, and is expressed in the uterus and placenta. ADM plays important roles in angiogenesis, vasodilation, and inflammation. Altered levels of ADM have been implicated in adverse pregnancy outcomes like fetal growth restriction and pre-eclampsia. Animal models can be useful tools for examining pregnancy pathophysiology. Much of what is known about ADM in pregnancy has been learned from the mouse model; however, the rat is a superior model of human placentation due to deep hemochorial invasion. Objective: We aim to explore the role of ADM at the maternal-placental interface and characterize placentation in ADM wild type and null rat pregnancy. ADM was localized within the rat placentation site by in situ hybridization. We used Crispr-Cas9-mediated genome editing to create a mutant Adm knockout rat. The mutation targeted Exon 2 and introduced a premature stop codon, resulting in a 206 bp deletion and truncated, nonfunctional protein. Germline transmission was confirmed. Heterozygous intercrosses failed to produce live null rats. Adm heterozygous pairs were bred to examine placental and fetal growth, development, and demise through gestation. Adm null placentas/fetuses were viable at gestation day (gd) 13.5, but all had demised or resorbed by gd 16.5. Growth restriction was evident by gd 13.5 in Adm null fetuses. Many Adm null conceptus demonstrated growth restriction and fetal-placental hemorrhage and infarct. On microscopic evaluation, some ADM deficient placentation sites demonstrated failed intrauterine trophoblast invasion. Adrenomedullin is expressed in trophoblast giant cells and decidual cells in early gestation. ADM deficiency disrupts trophoblast invasion at the uterine-placental interface in the rat. Loss of Adm results in abnormalities in placentation, fetal growth restriction, and fetal death by gd 16.5. Thus, Adrenomedullin is critical for successful placentation and favorable pregnancy outcomes.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Hyperglycemia results in significant pathophysiological changes of placental spiral artery remodeling and angiogenesis, further contributing to congenital defects.

Introduction: Hyperglycemic conditions achieved during pregnancy have been shown to have detrimental effects to fetal development and increase the prevalence of childhood comorbidities. However, the mechanisms in which diabetic pregnancies affect placental development and subsequently contribute to adverse health effects on the mother and offspring remain unclear. Research design and methods: Streptozotocin was used to induce gestational diabetes in mice. In this model, hyperglycemia was established at embryonic day 3.5 (E3.5). Pregnancy mass was collected at E10.5, E12.5, E14.5, and E16.5 for different assessments. Results: Both placental and embryonic weights were found to be significantly elevated at E16.5. At E14.5, a significantly larger junctional zone with increased number of glycogen trophoblasts was found in the placentas from hyperglycemic pregnancies (HG group) compared to the placentas from normoglycemic pregnancies (NG group). Importantly, the HG placenta exhibited decreased trophoblast giant cell (TGC) association and TUNEL+ cells, and increased expression of α-SMA on the spiral artery, suggesting arterial remodeling was impacted. Moreover, the interhemal membrane of the labyrinth layer, was found to be thicker in the HG placentas. Furthermore, hyperglycemia resulted in more offspring congenital defects, which were associated with a thicker interhemal membrane. Conclusions: Together, these results suggest that gestational diabetes perturbs proper placental development and function, specifically spiral artery remodeling and angiogenesis, thereby negatively impacting embryonic development.

HGF/c-Met signaling regulates early differentiation of placental trophoblast cells.

Depletion of hepatocyte growth factor (HGF) or mesenchymal-epithelial transition factor (c-Met) in mice leads to fetal lethality and placental maldevelopment. However, the dynamic change pattern of HGF/c-Met signaling during placental development and its involvement in the early differentiation of trophoblasts remain to be elucidated. In this study, using in situ hybridization assay, we elaborately demonstrated the spatial-temporal expression of Hgf and c-Met in mouse placenta from E5.5, the very early stage after embryonic implantation, to E12.5, when the placental structure is well developed. The concentration of the soluble form of c-Met (sMet) in maternal circulation peaked at E10.5. By utilizing the induced differentiation model of mouse trophoblast stem cells (mTSCs), we found that HGF significantly promoted mTSC differentiation into syncytiotrophoblasts (STBs) and invasive parietal trophoblast giant cells (PTGCs). Interestingly, sMet efficiently reversed the effect of HGF on mTSC differentiation. These findings indicate that HGF/c-Met signaling participates in regulating placental trophoblast cell fate at the early differentiation stage and that sMet acts as an endogenous antagonist in this aspect.

Decidual factors and vasoactive intestinal peptide guide monocytes to higher migration, efferocytosis and wound healing in term human pregnancy.

To explore the functional profile of circulating monocytes and decidual macrophages at term human pregnancy and their contribution to tissue repair upon stimulation ex vivo with decidual factors and the vasoactive intestinal peptide (VIP). Peripheral blood monocytes were isolated from pregnant and non-pregnant volunteers and tested in vitro with decidual explants from term placenta and VIP. The effect of VIP on decidual explants and the effect of its conditioned media on monocytes or decidual macrophages isolated by magnetic beads was carried out by RT-qPCR and ELISA for cytokines expression and release. Migration assays were performed in transwell systems. Efferocytosis was assessed in monocytes or decidual macrophages with CFSE-labelled autologous apoptotic neutrophils and quantified by flow cytometry. Monocyte and decidual macrophages wound healing capacity was evaluated using human endometrial stromal cell monolayers. Immunohistochemistry was performed in serial tissue sections of different placentas. VIP is expressed in the villi as well as in trophoblast giant cells distributed within the decidua of term placenta. VIP induced the expression of antiinflmammatory markers and monocyte chemoattractant CCL2 and CCL3 in decidual tissues. Monocytes presented higher migration towards decidual explants than CD4 and CD8 cells. VIP-conditioned monocytes displayed an enhanced efferocytosis and wound healing capacity comparable to that of decidual macrophages. Moreover limited efferocytosis of pregnant women monocytes was restored by VIP-induced decidual factors. Results show the conditioning of monocytes by decidual factors and VIP to sustain processes required for tissue repair and homeostasis maintenance in term placenta.

Placenta Creta: A Spectrum of Lesions Associated with Shallow Placental Implantation.

Background On placental histology, placenta creta (PC) ranges from clinical placenta percreta through placenta increta and accreta (clinical and occult) to myometrial fibers with intervening decidua. This retrospective study aimed to investigate the clinicopathologic correlations of these lesions. Methods A total of 169 recent consecutive cases with PC (group 1) were compared with 1661 cases without PC examined during the same period (group 2). The frequencies of 25 independent clinical and 40 placental phenotypes were statistically compared between the groups using chi-square test or analysis of variance where appropriate. Results Group 1 placentas, as compared with group 2 placentas, were statistically significantly (p < 0.05) associated with caesarean sections (11.2% vs. 7.5%), antepartum hemorrhage (17.7% vs 11.6.%), gestational hypertension (11.2% vs 4.3%), preeclampsia (11.8% vs 2.6%), complicated third stage of labor (18.9% vs 6.4%), villous infarction (14.2% vs 8.9%), chronic hypoxic patterns of placental injury, particularly the uterine pattern (14.8%, vs 9.6%), massive perivillous fibrin deposition (9.5% vs 5.3%), chorionic disc chorionic microcysts (21.9% vs 15.9%), clusters of maternal floor multinucleate trophoblasts (27.8% vs 21.2%), excessive trophoblasts of chorionic disc (24.3% vs 17.3%), segmental fetal vascular malperfusion (27.8% vs 19.9%), and fetal vascular ectasia (26.2% vs 15.2%). Conclusion Because of the association of PC with gestational hypertensive diseases, acute and chronic placental hypoxic lesions, increased extravillous trophoblasts in the chorionic disc, chorionic microcysts, and maternal floor trophoblastic giant cells, PC should be regarded as a lesion of abnormal placental implantation and abnormal trophoblast invasion rather than decidual deficiency only.

Hyperactivated Wnt-\u03b2-catenin signaling in the absence of sFRP1 and sFRP5 disrupts trophoblast differentiation through repression of Ascl2

BackgroundWnt signaling is a critical determinant for the maintenance and differentiation of stem/progenitor cells, including trophoblast stem cells during placental development. Hyperactivation of Wnt signaling has been shown to be associated with human trophoblast diseases. However, little is known about the impact and underlying mechanisms of excessive Wnt signaling during placental trophoblast development.ResultsIn the present work, we observed that two inhibitors of Wnt signaling, secreted frizzled-related proteins 1 and 5 (Sfrp1 and Sfrp5), are highly expressed in the extraembryonic trophoblast suggesting possible roles in early placental development. Sfrp1 and Sfrp5 double knockout mice exhibited disturbed trophoblast differentiation in the placental ectoplacental cone (EPC), which contains the precursors of trophoblast giant cells (TGCs) and spongiotrophoblast cells. In addition, we employed mouse models expressing a truncated β-catenin with exon 3 deletion globally and trophoblast-specifically, as well as trophoblast stem cell lines, and unraveled that hyperactivation of canonical Wnt pathway exhausted the trophoblast precursor cells in the EPC, resulting in the overabundance of giant cells at the expense of spongiotrophoblast cells. Further examination uncovered that hyperactivation of canonical Wnt pathway disturbed trophoblast differentiation in the EPC via repressing Ascl2 expression.ConclusionsOur investigations provide new insights that the homeostasis of canonical Wnt-β-catenin signaling is essential for EPC trophoblast differentiation during placental development, which is of high clinical relevance, since aberrant Wnt signaling is often associated with trophoblast-related diseases.

Aberrant effect of genistein on placenta development expressed through alteration in transforming growth factor-β1 and alkaline phosphatase across the maternal serum, the placenta and the amniotic fluid.

Objective(s):The mechanism via which genistein, the major isoflavone content of soya, adversely influenced placenta and fetal development was evaluated in pregnant laboratory rats.Materials and Methods:There were control, 2 mg/kg and 4 mg/kg genistein groups of rats with five sub-groups based on gestation termination day. At the end of the experiment, animals were sacrificed by CO2 and cervical dislocation, while plasma and serum were processed and stored. The abdomen was opened and the amniotic fluid was siphoned from the uterine sacs, processed and stored. The embryonic implants were excised, the placenta was separated from the fetus and weighed separately. Placenta homogenate was prepared from the harvested placenta, while the rest were processed for histological studies. Transforming growth factor (TGf-β1) and alkaline phosphatase (ALP) were assayed for in all samples. A significant decrease in the placenta and fetal weights, and a significant decrease in serum and placenta homogenate ALP levels were recorded in genistein groups.Results:There was a reduction in the Trophoblast giant cells population (TGCs). TGCs zone depth, perimeter, and an increase in the placenta and amniotic fluid’s TGf-β1 in all genistein groups at GD-13 towards term, and GD-18 and GD-20, respectively. Maternal plasma TGf-β1 was increased in 2 mg group early in pregnancy while its level significantly decreased in both 2 mg and 4 mg genistein groups at mid-gestation towards GD-19. Conclusion:Genistein aberrant effect on fetal development was via its adverse effect on TGCs proliferation and TGf-β1 activities in the placenta tissue.

Maternal and fetal alkaline ceramidase 2 is required for placental vascular integrity in mice.

Sphingolipids have been implicated in mammalian placental development and function, but their regulation in the placenta remains unclear. Herein we report that alkaline ceramidase 2 (ACER2) plays a key role in sustaining the integrity of the placental vasculature by regulating the homeostasis of sphingolipids in mice. The mouse alkaline ceramidase 2 gene (Acer2) is highly expressed in the placenta between embryonic day (E) 9.5 and E12.5. Acer2 deficiency in both the mother and fetus decreases the placental levels of sphingolipids, including sphingoid bases (sphingosine and dihydrosphingosine) and sphingoid base-1-phosphates (sphingosine-1-phosphate and dihydrosphingosine-1-phosphate) and results in the in utero death of ≈50% of embryos at E12.5 whereas Acer2 deficiency in either the mother or fetus has no such effects. Acer2 deficiency causes hemorrhages from the maternal vasculature in the junctional and/or labyrinthine zones in E12.5 placentas. Moreover, hemorrhagic but not non-hemorrhagic Acer2-deficient placentas exhibit an expansion of parietal trophoblast giant cells with a concomitant decrease in the area of the fetal blood vessel network in the labyrinthine zone, suggesting that Acer2 deficiency results in embryonic lethality due to the atrophy of the fetal blood vessel network in the placenta. Taken together, these results suggest that ACER2 sustains the integrity of the placental vasculature by controlling the homeostasis of sphingolipids in mice.

Maternal oxycodone treatment causes pathophysiological changes in the mouse placenta

IntroductionPregnant women are increasingly being prescribed and abusing opioid drugs. As the primary communication organ between mother and conceptus, the placenta may be vulnerable to opioid effects but also holds the key to better understanding how these drugs affect long-term offspring health. We hypothesized that maternal treatment with oxycodone (OXY), the primary opioid at the center of the current crisis, deleteriously affects placental structure and gene expression patterns. MethodsFemale mice were treated daily with 5 mg OXY/kg or saline solution (Control, CTL) for two weeks prior to breeding and until placenta were collected at embryonic age 12.5. A portion of the placenta was fixed for histology, and the remainder was frozen for RNA isolation followed by RNAseq. ResultsMaternal OXY treatment reduced parietal trophoblast giant cell (pTGC) area and decreased the maternal blood vessel area within the labyrinth region. OXY exposure affected placental gene expression profiles in a sex dependent manner with female placenta showing up-regulation of many placental enriched genes, including Ceacam11, Ceacam14, Ceacam12, Ceacam13, Prl7b1, Prl2b1, Ctsq, and Tpbpa. In contrast, placenta of OXY exposed males had alteration of many ribosomal proteins. Weighted correlation network analysis revealed that in OXY female vs. CTL female comparison, select modules correlated with OXY-induced placental histological changes. Such associations were lacking in the male OXY vs. CTL male comparison. DiscussionResults suggest OXY exposure alters placental histology. In response to OXY exposure, female placenta responds by upregulating placental enriched transcripts that are either unchanged or downregulated in male placenta. Such changes may shield female offspring from developmental origins of health and disease-based diseases.

The regulation of trophoblast invasion and decidual reaction by matrix metalloproteinase-2, metalloproteinase-7, and metalloproteinase-9 expressions in the rat endometrium.

PurposeWe aimed to evaluate how matrix metalloproteinases (MMPs) regulate the trophoblast invasion and placentation.MethodsFemale rats were divided into the estrous cycle and early pregnancy day groups. Obtained uterine tissues and implantation sites were processed for immunofluorescence and real‐time PCR examinations.ResultsThe mRNA expression of MMP‐7 was higher than MMP‐2 and MMP‐9. Immunofluorescence findings confirmed that MMP‐2, MMP‐7, and MMP‐9 were localized in the endometrial stroma, while MMP‐7 was high in glandular and lining epithelial cells throughout the entire estrous cycle. However, their immunolocalizations and mRNA expressions were dramatically changed with the early pregnancy days. The MMP‐7 reached very strong immunostaining in the giant trophoblast cells (GTCs), and the cytoplasm of mature and differentiating decidual cells, whereas MMP‐2 and MMP‐9 were mostly seen in the primary decidual zone (PDZ), GTCs, and the endothelium of blood vessels.ConclusionsAll three MMPs seemed likely to be a key mediator of trophoblast invasion into the decidual region as well as angiogenesis during the placentation process. Due to the strong and wide expression of MMP‐7 in the mature decidua, it could be suggested that MMP‐7 is important for decidual ECM remodeling and it might be used as a new marker of decidual reaction.

Transcriptomic analysis reveals differential gene expression, alternative splicing, and novel exons during mouse trophoblast stem cell differentiation

BackgroundDifferentiation of mouse trophoblast stem cells (TSCs) to trophoblast giant cells (TGCs) has been widely used as a model system to study placental development and function. While several differentially expressed genes, including regulators of TSC differentiation, have been identified, a comprehensive analysis of the global expression of genes and splice variants in the two cell types has not been reported.ResultsHere, we report ~ 7800 differentially expressed genes in TGCs compared to TSCs which include regulators of the cell cycle, apoptosis, cytoskeleton, cell mobility, embryo implantation, metabolism, and various signaling pathways. We show that several mitotic proteins, including Aurora A kinase, were downregulated in TGCs and that the activity of Aurora A kinase is required for the maintenance of TSCs. We also identify hitherto undiscovered, cell-type specific alternative splicing events in 31 genes in the two cell types. Finally, we also report 19 novel exons in 12 genes which are expressed in both TSCs and TGCs.ConclusionsOverall, our results uncover several potential regulators of TSC differentiation and TGC function, thereby providing a valuable resource for developmental and molecular biologists interested in the study of stem cell differentiation and embryonic development.

Persistent Human KIT Receptor Signaling Disposes Murine Placenta to Premature Differentiation Resulting in Severely Disrupted Placental Structure and Functionality

Activating mutations in the human KIT receptor is known to drive severe hematopoietic disorders and tumor formation spanning various entities. The most common mutation is the substitution of aspartic acid at position 816 to valine (D816V), rendering the receptor constitutively active independent of ligand binding. As the role of the KIT receptor in placental signaling cascades is poorly understood, we analyzed the impact of KITD816V expression on placental development using a humanized mouse model. Placentas from KITD816V animals present with a grossly changed morphology, displaying a reduction in labyrinth and spongiotrophoblast layer and an increase in the Parietal Trophoblast Giant Cell (P-TGC) layer. Elevated differentiation to P-TGCs was accompanied with reduced differentiation to other Trophoblast Giant Cell (TGC) subtypes and by severe decrease in proliferation. The embryos display growth retardation and die in utero. KITD816V-trophoblast stem cells (TSC) differentiate much faster compared to wild type (WT) controls. In undifferentiated KITD816V-TSCs, levels of Phosphorylated Extracellular-signal Regulated Kinase (P-ERK) and Phosphorylated Protein Kinase B (P-AKT) are comparable to wildtype cultures differentiating for 3–6 days. Accordingly, P-TGC markers Placental Lactogen 1 (PL1) and Proliferin (PLF) are upregulated as well. The results reveal that KIT signaling orchestrates the fine-tuned differentiation of the placenta, with special emphasis on P-TGC differentiation. Appropriate control of KIT receptor action is therefore essential for placental development and nourishment of the embryo.

A mouse model of placenta accreta spectrum

IntroductionPlacenta Accreta Spectrum (PAS) disorder is one of the leading causes of maternal morbidity and mortality due to uncontrollable hemorrhage. The greatest risk factor for development of PAS is prior uterine surgery, frequently cesarean delivery. Despite considerable clinical knowledge, animal models of PAS are lacking. To address this, we used two surgical approaches to create uterine scarring in peripartum and non-pregnant CD-1 mice. Il10−/− mice, with a pro-inflammatory phenotype were also studied. MethodsIn peripartum mice, a hysterotomy was performed to simulate a cesarean section. The second approach utilized endometrial curettage in non-pregnant mice. Sham-operated mice served as control. Following recovery, females were mated. On gestation day 16, pregnant females were euthanized, and the uterus was excised. Tissue was fixed, sectioned, and stained with H&E or cytokeratin immunohistochemistry. The cytokeratin-positive area extending beyond the trophoblast giant cells was measured by quantitative image analysis. Disruption of the circular (inner myometrium) smooth muscle was scored semi-quantitatively. ResultsIn surgically scarred mice, trophoblast invasion was deeper relative to control mice, regardless of surgical method. The myometrium in experimental mice showed significant disruption compared to sham controls. Results from CD-1 and Il10−/− mice were similar, with the latter showing more severe pathology. DiscussionWhile further refinement of surgical method is required, our data indicate that surgical uterine scarring in mice represents a promising model of PAS.

Persistent DNA Damage and Senescence in the Placenta Impacts Developmental Outcomes of Embryos.

Cohesin is an evolutionarily conserved chromosome-associated protein complex essential for chromosome segregation, gene expression, and repair of DNA damage. Mutations that affect this complex cause the human developmental disorder Cornelia de Lange syndrome (CdLS), thought to arise from defective embryonic transcription. We establish a significant role for placental defects in the development of CdLS mouse embryos (Nipbl and Hdac8). Placenta is a naturally senescent tissue; we demonstrate that persistent DNA damage potentiates senescence and activates cytokine signaling. Mutant embryo developmental outcomes are significantly improved in the context of a wild-type placenta or by genetically restricting cytokine signaling. Our study highlights that cohesin is required for maintaining ploidy and the repair of spontaneous DNA damage in placental cells, suggesting that genotoxic stress and ensuing placental senescence and cytokine production could represent a broad theme in embryo health and viability.

Role of cell cycling and polyploidy in placental trophoblast of different mammalian species.

The trophoblast cells that take part in placenta formation are characterized by different modes of multiplication of their genome that largely designates their eu- or aneuploidy level. The two main ways of genome multiplication are described in different degree: (a) endoreduplication that involves almost complete shutdown of mitosis and (b) reduced mitosis ('endomitosis') in which, by contrast, entry into mitosis and the passage of its initial stages is a prerequisite of genome multiplication. Endoreduplication observed in the trophoblast giant cells (TGC) in a range of mammalian species implies uncoupling of DNA replication from mitosis achieved by reduction of mitotic Cdk activity. The key role in the regulation of endoreduplication and endomitosis play activity of APC/C complex, geminin and E2F family. A programme of genome multiplication and cell cycle progression may include depolyploidization achieved by specific mitotic or non-mitotic (amitotic) division of the giant nucleus. In some mammalian species (Rodents), this process represents the final step of the giant cell lifespan that coincides with complete cessation of cell or genome reproduction. Meantime, in other species the process may take part in cell reproduction during lengthy pregnancy. The dynamics of fox and human polyploidization is similar by the possibility of a simultaneous increase in the proportion of endopolyploid and low-polyploid cells. Reduced mitoses, endoreduplication and depolyploidization appear to be an evolution strategy allowing to generate the functionally different trophoblast cell populations depending of the lifestyle of life of the animal species. Some placental pathologies may be accounted for disturbance of the programme of the cell/genome reproduction of the giant and low-ploid cell populations.

RNA Sequencing for Gene Expression Profiles in Peripheral Blood Mononuclear Cells with Ankylosing Spondylitis RNA.

Several previous studies have attempted to investigate the regulatory mechanisms underlying gene expression in ankylosing spondylitis (AS). However, the specific molecular pathways underlying this condition remain unclear. Previous research used next-generation RNA sequencing to identify a series of differentially expressed genes (DEGs) in peripheral blood mononuclear cells (PBMCs) when compared between patients with AS and healthy controls, thus implying that these DEGs may be related to AS. Furthermore, by screening these DEGS, it may be possible to facilitate clinical diagnosis and optimize treatment strategies. In order to test this hypothesis, we recruited 15 patients with AS and 15 healthy controls. We randomly selected five subjects from each group of patients for RNA sequencing analysis. Sequence reads were generated by an Illumina HiSeq2500 platform and mapped on to the human reference genome using HISAT2. We successfully identified 973 significant DEGs (p < 0.05) in PBMCs. When compared with controls, 644 of these genes were upregulated (with a fold change (FC) > 2) in AS patients and 329 were downregulated (FC < 0.5). Our analysis identified numerous genes related to immune response. Gene Ontology (GO) analysis indicated that these DEGs were significantly related to the positive regulation of epidermal growth factor-activated receptor activity, the positive regulation of the ERBB (erb-b2 receptor tyrosine kinase) signaling pathway, the differentiation of trophoblast giant cells, oxygen transport, immune-related pathways, and inflammation-related pathways. The DEGs were also closely related to the TNF and NF-κB signaling pathways. Six DEGs were verified by quantitative real-time polymerase chain reaction (qRT-PCR). Receiver operating characteristic (ROC) curve analysis indicated that IL6 may represent a useful biomarker for diagnosing AS. The development of new biomarkers may help us to elucidate the specific mechanisms involved in the development and progression of AS.

Dose-dependent structural and immunological changes in the placenta and fetal brain in response to systemic inflammation during pregnancy.

Systemic maternal inflammation is associated with adverse neonatal sequelae. We tested the hypothesis that IL-1β is a key inflammatory regulator of adverse pregnancy outcomes. Pregnant mice were treated with intraperitoneal injections of IL-1β (0, 0.1, 0.5, or 1μg) from embryonic day (E)14 to E17. Placenta and fetal brains were harvested and analyzed for morphologic changes and IL-1β signaling markers. As compared with non-treated dams, maternal injections with IL-1β resulted in increased p-NF-κB and caspase-1 in placentas and fetal brains, but not consistently in spleens, suggesting induction of intrinsic IL-1β production. These findings were confirmed by increased levels of IL-1β in the placentas of the IL-1β-treated dams. Systemic treatment of dams with IL-1β suppressed Stat1 signaling. Maternal inflammation caused by IL-1β treatment reduced fetal viability to 80.6% and 58.9%, in dams treated with either 0.5 or 1μg of IL-1β, respectively. In the placentas, there was an IL-1β dose-dependent distortion of the labyrinth structure, decreased numbers of mononuclear trophoblast giant cells, and reduced proportions of endothelial cells as compared to placentas from control dams. In fetal brains collected at E17, there was an IL-1β dose-dependent reduction in cortical neuronal morphology. This work demonstrates that systemic IL-1β injection causes dose-dependent structural and functional changes in the placenta and fetal brain.