WNT and NOTCH signaling in human trophoblast development and differentiation

Baicalein prevents pregnancy loss by maintaining regulatory T cell activation through inhibition of the TLR4/NF-κB signaling pathway

INTRODUCTION

Unexplained recurrent spontaneous abortion (URSA) involves multifactorial etiologies, with regulatory T cells (Tregs) playing a pivotal role in maintaining immune tolerance during pregnancy. Baicalein, a flavonoid from Scutellaria baicalensis, exhibits anti-inflammatory and immunomodulatory properties. This study evaluates baicalein's therapeutic potential in mitigating URSA via the TLR4/NF-κB signaling pathway.

METHODS

A URSA mouse model was used, and baicalein was administered intraperitoneally. Pregnancy outcomes, abortion rates, and placental morphology were assessed on gestational day 14 (G14). Treg cells were quantified via flow cytometry, and gene/protein expression levels were analyzed by immunohistochemistry, Western blotting, and real-time PCR. In vitro experiments on ihESCs further investigated the role of the TLR4/NF-κB pathway.

RESULTS

Baicalein reduced abortion rates from 33.3 % in URSA mice to 21.6 % (low dose) and 14.8 % (high dose), improved embryonic development by altering placental structure and decidual morphology, and reduced inflammation at the maternal-fetal interface. It expanded Treg cells and enhanced the expression of IGFBP-1 and PRL, markers of endometrial decidualization, and decreased TLR4, p-P65, and P65 expression. In vitro, baicalein's effects were abrogated by TLR4 inhibition, confirming pathway specificity.

DISCUSSION

Baicalein improved pregnancy outcomes by enhancing Treg function and promoting decidualization via TLR4/NF-κB pathway inhibition. These findings highlight baicalein's potential as a therapeutic agent for URSA.

In vitro differentiation of macaque extravillous trophoblasts in a low oxygen environment

INTRODUCTION

Early primate placental development occurs within a low oxygen (O2) environment, whereas in vitro differentiation of trophoblasts is performed at supraphysiologic O2 levels. Macaque trophoblast stem cells (TSCs) are capable of differentiation to extravillous trophoblasts (EVTs) in vitro, yet the morphological heterogeneity observed across cells lines necessitates evaluation of optimal culture conditions. Our objectives were to determine the impact of oxygen on the in vitro differentiation of macaque TSCs and to refine the molecular characterization of TSC-differentiated EVTs.

METHODS

Macaque TSCs were differentiated to EVTs in either 20% or 5% O2. Gene and protein expression profiles were compared between TSCs and EVTs and between differentiation conditions. Immunohistochemical analysis was performed on early gestation macaque placental tissues to assess in vivo expression of Ki-67, NCAM1 and monkey chorionic gonadotropin (mCG).

RESULTS

EVTs differentiated in 20% O2 had significantly higher expression of CGA, CGB and NOTCH2 and decreased HIF1A expression compared to those cultured in 5% O2. Regardless of oxygen condition, nearly all EVTs expressed NCAM1 and Mamu-AG, the macaque-specific homolog of human EVT marker HLA-G. In vivo placental expression of NCAM1 was restricted to EVTs within the trophoblastic shell and endovasculature, revealing a macaque EVT marker within the placenta.

DISCUSSION

Reduced oxygen minimally impacted macaque EVT differentiation in vitro. Elevated expression of the endovascular EVT marker NOTCH2 potentially suggests that 20% O2 supported differentiation of more mature EVTs. Altogether, a standard 20% O2 environment supports macaque EVT differentiation in vitro and the results further validate the identity of macaque TSC-differentiated EVTs.

Stem Cell Markers LGR5, LGR4 and Their Immediate Signalling Partners are Dysregulated in Preeclampsia

Leucine-rich repeat-containing G protein-coupled receptors 5/4 (LGR5/LGR4) are critical stem cell markers in epithelial tissues including intestine. They agonise wingless-related integration site (WNT) signalling. Until now, LGR5/LGR4 were uncharacterised in placenta, where analogous functions may exist. We characterised LGR5/LGR4, their ligands/targets in human placenta, with further assessments on dysregulation in preeclampsia/fetal growth restriction (FGR). LGR5 mRNA was unaltered in first trimester (n = 11), preterm (n = 9) and term (n = 11) placental lysate. LGR5 was enriched in human trophoblast stem cells (hTSCs) and downregulated with differentiation to extravillous trophoblasts (p < 0.0215) and syncytiotrophoblasts (p < 0.0350). In situ hybridisation localised LGR5 to unique, proliferative MKI67 + mononuclear trophoblasts underlying syncytium which concurred with proposed progenitor identities in single-cell transcriptomics. LGR5 expression was significantly reduced in placentas from early-onset preeclampsia (p < 0.0001, n = 81 versus n = 19 controls), late-onset preeclampsia (p = 0.0046, n = 20 versus n = 33 controls) and FGR (p = 0.0031, n = 34 versus n = 17 controls). LGR4 was elevated in first trimester versus preterm and term placentas (p = 0.0412), in placentas with early-onset preeclampsia (p = 0.0148) and in FGR (p = 0.0417). Transcriptomic analysis and in vitro hTSC differentiation to both trophoblast lineages suggested LGR4 increases with differentiation. Single-nucleus RNA sequencing of placental villous samples supported LGR5 and LGR4 localisation findings. Hypoxia/proinflammatory cytokine treatment modelling elements experienced by the placenta in placental insufficiency pathogenesis did not significantly alter LGR5/LGR4. Ligands R-spondins 1/3/4, and neutralising targets ring finger protein 43 (RNF43) and zinc and ring finger 3 (ZNRF3) were also reduced in placentas from preeclamptic pregnancies. This study is the first to describe LGR5/LGR4 and their signalling partner expression in human placenta. Their dysregulations in the preeclamptic placenta allude to disruptions to integral trophoblast stem cell function/differentiation that may occur during placental development related to WNT signalling.

CTNNB1 and CDH1 Regulate Trophoblast Cell Adhesion and Junction Formation in Yak Placental Tissue at Different Gestational Stages

Yaks (Bos grunniens), which are distributed across the Tibetan Plateau and other high-altitude regions, are vital livestock that provide essential resources for local herders and have significant economic and ecological value [...].

Maternal α-cypermethrin and permethrin exert differential effects on fetal growth, placental morphology, and fetal neurodevelopment in mice

Pyrethroid insecticides represent a broad class of chemicals used widely in agriculture and household applications. Human studies show mixed effects of maternal pyrethroid exposure on fetal growth and neurodevelopment. Assessment of shared pyrethroid metabolites as a biomarker for exposure obscures effects of specific chemicals within this broader class. To better characterize pyrethroid effects on fetal development, we investigated maternal exposure to permethrin, a type I pyrethroid, and α-cypermethrin, a type II pyrethroid, on fetal development in mice. Pregnant CD1 mice were exposed to permethrin (1.5, 15, or 50 mg/kg), α-cypermethrin (0.3, 3, or 10 mg/kg), or corn oil vehicle via oral gavage on gestational days (GD) 6-16. Effects on fetal growth, placental toxicity, and neurodevelopment were evaluated at GD 16. Cypermethrin, but not permethrin, significantly reduced fetal growth and altered placental layer morphology. Placental RNAseq analysis revealed downregulation of genes involved in extracellular matrix remodeling in response to α-cypermethrin. Both pyrethroids induced shifts in fetal dorsal forebrain microglia morphology from ramified to ameboid states; however, effects of α-cypermethrin were more pronounced. The α-cypermethrin transcriptome of fetal dorsal forebrain implicated altered glutamate receptor signaling, synaptogenesis, and c-AMP signaling. Coregulated gene modules in individual placenta and fetal dorsal forebrain pairs were correlated and overlapped in biological processes characterizing synapses, mitotic cell cycle, and chromatin organization, suggesting placenta-fetal brain shared mechanisms with α-cypermethrin exposure. In summary, maternal type II pyrethroid α-cypermethrin exposure but not type I pyrethroid permethrin significantly affected placental development, fetal growth, and neurodevelopment, and these effects were linked.

Impact of Prenatal Dietary Soy on Cerebellar Neurodevelopment and Function in Experimental Fetal Alcohol Spectrum Disorder

Background: Prenatal alcohol exposure (PAE) models can cause neurodevelopmental abnormalities like those observed in fetal alcohol spectrum disorder (FASD). Previous studies link experimental PAE effects in the brain to impaired signaling through insulin/IGF and Notch pathways that mediate neuronal survival, growth, migration, energy metabolism, and plasticity. Importantly, concurrent administration of peroxisome proliferator-activated receptor agonists or dietary soy prevented many aspects of FASD due to their insulin-sensitizing, anti-inflammatory, and antioxidant properties. Objective: To determine if dietary soy interventions during pregnancy would be sufficient to normalize central nervous system structure and function, we examined the effects of maternal gestation-limited dietary soy on cerebellar postnatal development, motor function, and critical signaling pathways. Methods: Pregnant Long Evans rats were fed isocaloric liquid diets containing 0% or 26% caloric ethanol with casein or soy isolate as the protein source. The ethanol and soy feedings were discontinued upon delivery. The offspring were subjected to rotarod motor function tests, and on postnatal day 35, they were sacrificed to harvest cerebella for histological and molecular studies. Results: Despite the postnatal cessation of alcohol exposure, chronic gestational exposure reduced brain weight, caused cerebellar hypoplasia, and impaired motor performance. Gestational dietary soy prevented the ethanol-associated reduction in brain weight and largely restored the histological integrity of the cerebellum but failed to normalize motor performance. Ethanol withdrawal abolished the impairments in insulin/IGF signaling that were previously associated with ongoing ethanol exposures, but ethanol's inhibitory effects on Notch and Wnt signaling persisted. Soy significantly increased cerebellar expression of the insulin and IGF-1 receptors and abrogated several ethanol-associated impairments in Notch and Wnt signaling. Conclusions: Although gestation-restricted dietary soy has significant positive effects on neurodevelopment, optimum prevention of FASD's long-term effects will likely require dietary soy intervention during the critical periods of postnatal development, even after alcohol exposures have ceased.

Molecular and Functional Convergences Associated with Complex Multicellularity in Eukarya

A key trait of Eukarya is the independent evolution of complex multicellularity in animals, land plants, fungi, brown algae, and red algae. This phenotype is characterized by the initial exaptation of cell-cell adhesion genes followed by the emergence of mechanisms for cell-cell communication, together with the expansion of transcription factor gene families responsible for cell and tissue identity. The number of cell types is commonly used as a quantitative proxy for biological complexity in comparative genomics studies. While expansions of individual gene families have been associated with variations in the number of cell types within individual complex multicellular lineages, the molecular and functional roles responsible for the independent evolution of complex multicellular across Eukarya remain poorly understood. We employed a phylogeny-aware strategy to conduct a genomic-scale search for associations between the number of cell types and the abundance of genomic components across a phylogenetically diverse set of 81 eukaryotic species, including species from all complex multicellular lineages. Our annotation schemas represent 2 complimentary aspects of genomic information: homology, represented by conserved sequences, and function, represented by Gene Ontology terms. We found many gene families sharing common biological themes that define complex multicellular to be independently expanded in 2 or more complex multicellular lineages, such as components of the extracellular matrix, cell-cell communication mechanisms, and developmental pathways. Additionally, we describe many previously unknown associations of biological themes and biological complexity, such as expansions of genes playing roles in wound response, immunity, cell migration, regulatory processes, and response to natural rhythms. Together, our findings unveil a set of functional and molecular convergences independently expanded in complex multicellular lineages likely due to the common selective pressures in their lifestyles.

Maternal diet quality and circulating extracellular vesicle and particle miRNA during pregnancy

PURPOSE

During pregnancy, extracellular vesicle and particle microRNAs (EVP miRNA) in maternal circulation have the capacity to cross the placenta and facilitate maternal-fetal communication. Both dysregulation of circulating EVP miRNA during pregnancy and maternal diet quality have been previously associated with pregnancy complications and adverse birth outcomes. However, little is known about how maternal diet influences circulating EVP miRNA during pregnancy. This study assesses associations between maternal diet quality, as measured by the Alternative Healthy Eating Index (2010; AHEI-2010), and EVP miRNA levels in maternal circulation during pregnancy.

METHODS

In a pilot study of 53 pregnant participants in the New Hampshire Birth Cohort Study, maternal diet quality was assessed using AHEI-2010 and plasma (mean gestational age at blood collection: 28.8 weeks) EVP miRNA were profiled using the NanoString nCounter platform which interrogates 798 miRNA transcripts.

RESULTS

In covariate-adjusted models, the AHEI-2010 adherence score was negatively associated (P < 0.05) with the number of unique miRNA transcripts detectable in each sample. In post hoc analyses, greater consumption of red and processed meats was positively associated with levels of 7 miRNA (Q < 0.05), including hsa-miR-512-5p (PBonf < 0.01), a member of the placenta-specific chromosome 19 miRNA cluster.

CONCLUSION

We identified associations between the consumption of red and processed meat and levels of circulating select EVP miRNA during pregnancy, including placenta-specific miRNA and miRNA with target genes overrepresented in pathways involved in placental development. Additional research is needed to assess whether alterations in maternal circulating EVP miRNA may mediate maternal diet quality's impacts on pregnancy and birth outcomes.

Identification and preliminary validation of biomarkers associated with mitochondrial and programmed cell death in pre-eclampsia

Background

The involvement of mitochondrial and programmed cell death (mtPCD)-related genes in the pathogenesis of pre-eclampsia (PE) remains inadequately characterized.

Methods

This study explores the role of mtPCD genes in PE through bioinformatics and experimental approaches. Differentially expressed mtPCD genes were identified as potential biomarkers from the GSE10588 and GSE98224 datasets and subsequently validated. Hub genes were determined using support vector machine, least absolute shrinkage and selection operator, and Boruta based on consistent expression profiles. Their performance was assessed through nomogram and artificial neural network models. Biomarkers were subjected to localization, functional annotation, regulatory network analysis, and drug prediction. Clinical validation was conducted via real-time quantitative polymerase chain reaction (RT-qPCR), immunofluorescence, and Western blot.

Results

Four genes [solute carrier family 25 member 5 (SLC25A5), acyl-CoA synthetase family member 2 (ACSF2), mitochondrial fission factor (MFF), and phorbol-12-myristate-13-acetate-induced protein 1 (PMAIP1)] were identified as biomarkers distinguishing PE from normal controls. Functional analysis indicated their involvement in various biological pathways. Immune analysis revealed associations between biomarkers and immune cell activity. A regulatory network was informed by biomarker expression and database predictions, in which KCNQ1OT1 modulates ACSF2 expression via hsa-miR-200b-3p. Drug predictions, including clodronic acid, were also proposed. Immunofluorescence, RT-qPCR, and Western blot confirmed reduced expression of SLC25A5, MFF, and PMAIP1 in PE, whereas ACSF2 was significantly upregulated.

Conclusion

These four mtPCD-related biomarkers may play a pivotal role in PE pathogenesis, offering new perspectives on the disease's diagnostic and mechanistic pathways.

Decreased expression of LEF1 caused defective decidualization by inhibiting IL-11 expression in patients with adenomyosis

Reduced lymphoid enhancer-binding factor 1 (LEF1) expression in patients with adenomyosis during the mid-secretory phase leads to impaired endometrial receptivity, affecting embryo implantation. This study investigated the molecular mechanisms underlying reduced endometrial receptivity in 25 adenomyosis patients and 25 controls. Functional experiments were conducted using human endometrial stromal cells (HESCs) and TERT-immortalized HESCs(T-HESCs), with final validation performed using a mouse model. Western blot and quantitative real-time polymerase chain reaction (RT-qPCR) analyses revealed that patients with adenomyosis showed a marked decrease in LEF1 expression in the stromal cells of the endometrium during the mid-secretory phase. In vitro experiments demonstrated that LEF1 knockdown in stromal cells led to impaired decidualization. Transcriptome sequencing, dual-luciferase reporter assays, and chromatin immunoprecipitation (ChIP) experiments showed that LEF1 could bind to the promoter region of interleukin (IL)-11 and promote its transcription, and IL-11 expression was also found to be downregulated in adenomyosis patients. Overexpression of IL-11 rescued the impaired decidualization caused by decreased LEF1 expression. In the in vitro co-culture model, LEF1/IL-11 knockdown led to a reduction in embryo implantation area, which was partially restored upon IL-11 overexpression. In the adenomyosis mouse model, we observed a decrease in LEF1 expression and a reduction in implantation sites compared to control mice, accompanied by impaired decidualization and receptivity. Notably, supplementation with IL-11 restored the number of implantation sites. The decrease in fertility due to reduced endometrial receptivity in adenomyosis patients is a significant clinical issue in assisted reproductive technology. This research provides insights into one potential molecular mechanism underlying this decreased receptivity, with a specific focus on the reduced expression of LEF1 in the endometrial stromal cells during the mid-secretory phase in adenomyosis patients. Our findings offer new perspectives for clinical strategies to improve endometrial receptivity in patients with adenomyosis, potentially enhancing their chances of successful pregnancy.

Upregulated YTHDC1 mediates trophoblastic dysfunction inducing preterm birth in ART conceptions through enhanced RPL37 translation

Assisted reproductive technology (ART) pregnancies present a higher risk of singleton preterm birth than natural pregnancies, but the underlying molecular mechanism remains largely unknown. RNA m6A modification is a key epigenetic mechanism regulating cellular function, but the role of m6A modification, especially its "reader" YTHDC1, in preterm delivery remains undefined. To delineate the role and epigenetic mechanism of m6A modification in ART preterm delivery, the effects of YTHDC1 on trophoblastic function were evaluated by CCK-8, EdU, Transwell, and flow cytometry analyses post its overexpression or knockdown. Downstream signaling pathways of YTHDC1 were investigated by RNA-seq, and targeted mRNAs were explored by RIP-seq and MeRIP-seq. Upstream transcriptional factors of YTHDC1 were determined by ChIP-seq and luciferase reporter assays. Elevated YTHDC1 was detected in human ART-conceived preterm placentas and in murine preterm placentas post estradiol (E2) exposure. In vitro experiments showed that YTHDC1 promoted trophoblastic cell proliferation and migration, but inhibited cell apoptosis. Mechanistically, E2 was proven to upregulate YTHDC1 expression via retinoid X receptor alpha (RXRA) in trophoblastic cells. Enhanced YTHDC1 expression augmented the translation of RPL37 in an m6A-dependent manner by binding to m6A-modified RPL37 mRNA and concomitantly promoted the overall translational output. Importantly, administration of siRNA targeting YTHDC1 effectively delayed the progression of preterm delivery. In conclusion, the identified E2/RXRA/YTHDC1/RPL37 axis provides new insights into the epigenetic mechanism underlying ART-associated preterm delivery. The findings offer a potential prognostic biomarker and therapeutic target for preterm delivery.

Multi-omics PGT: re-evaluation of euploid blastocysts for implantation potential based on RNA sequencing

STUDY QUESTION

In addition to chromosomal euploidy, can the transcriptome of blastocysts be used as a novel predictor of embryo implantation potential?

SUMMARY ANSWER

This retrospective analysis showed that based on differentially expressed genes (DEGs) between euploid blastocysts which resulted and did not result in a clinical pregnancy, machine learning models could help improve implantation rates by blastocyst optimization.

WHAT IS KNOWN ALREADY

Embryo implantation is a multifaceted process, with implantation loss and pregnancy failure related not only to blastocyst euploidy but also to the intricate dialog between blastocyst and endometrium. Although in vitro studies have revealed the characteristics of trophectoderm (TE) differentiation in implanted blastocysts and the function of TE placentation at the implantation site, the precise molecular mechanisms of embryo implantation and their clinical application remain to be fully elucidated.

STUDY DESIGN, SIZE, DURATION

This study involved 102 patients who underwent 111 cycles for preimplantation genetic testing for aneuploidies (PGT-A) between March 2022 and July 2023.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The study included 412 blastocysts biopsied at Day 5 [D5] or Day 6 [D6] for patients who underwent PGT-A. The biopsy lysates were split and subjected to DNA and RNA sequencing (DNA- and RNA-seq). One part was used for PGT-A to detect DNA copy number variations, whereas the other part was assessed simultaneously by RNA-seq to determine the transcriptome characteristics. To validate the reliability and accuracy of RNA-seq obtained from this strategy, we initially analyzed the transcriptome of blastocysts with chromosomal aneuploidies. Subsequently, we compared the transcriptomic features of blastocysts with different rates of formation (D5 vs D6) and investigated the network of interactions between key blastulation genes and the receptive endometrium. Then to evaluate the implantation potential of euploid blastocysts, we identified DEGs between euploid blastocysts that resulted in clinical pregnancy (defined as the presence of a gestational sac detected by ultrasound after 5 weeks) and those that did not. These DEGs were then employed to construct a predictive model for optimizing blastocyst selection.

MAIN RESULTS AND THE ROLE OF CHANCE

The successful detection rate of PGT-A was remarkably high at 99.8%. The RNA data may infer aneuploidy for both trisomy and monosomy. Between the euploid blastocysts that formed on D5 and D6, 187 DEGs were predominantly involved in cell differentiation for embryonic placenta development, the PPAR signaling pathway, and the Notch signaling pathway. These D5/D6 DEGs also exhibited a functional dialog with the receptive phase endometrium-specific genes through protein-protein interaction networks, indicating that the embryo undergoes further differentiation for post-implantation development. Furthermore, a modeling strategy using 280 DEGs between blastocysts leading to successful clinical pregnancies or failing to produce clinical pregnancies was implemented to refine the euploid embryo optimization, achieving areas under the curves of 0.88, 0.71, and 0.84 for the random forest (RF), support vector machine, and linear discriminant analysis models, respectively. Finally, a retrospective analysis of 83 transferred euploid blastocysts using the RF model identified three types of euploid embryos with a decreasing trend in implantation potential. Notably, the implantation rate of the good group was significantly higher than that of the moderate group (88.6% vs 50.0% P = 0.001) and that of the moderate group was higher than that of the poor group (50.0% vs 20.8%, P = 0.035).

LIMITATIONS, REASONS FOR CAUTION

The sample size was insufficient; thus, a prospective study is needed to verify the clinical effectiveness of the above model. Because we did not analyze blastocysts that led only to biochemical pregnancies but failed clinical pregnancies separately, our classification system still must be modified to screen these embryos.

WIDER IMPLICATIONS OF THE FINDINGS

Transcriptomic analysis of blastocysts offers a novel approach for predicting embryo implantation potential, which can be utilized to optimize clinical embryo selection. The ranking system may be effective in reducing the times and costs involved in achieving a clinical pregnancy.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by the "Pioneer" and "Leading Goose" R&D Program of Zhejiang (No. 2023C03034), the National Natural Science Foundation of China (82101709), and the National Key Research and Development Program for Young Scientists of China (No. 2022YFC2702300). The authors state no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Spatial multiomic landscape of the human placenta at molecular resolution

Successful pregnancy relies directly on the placenta's complex, dynamic, gene-regulatory networks. Disruption of this vast collection of intercellular and intracellular programs leads to pregnancy complications and developmental defects. In the present study, we generated a comprehensive, spatially resolved, multimodal cell census elucidating the molecular architecture of the first trimester human placenta. We utilized paired single-nucleus (sn)ATAC (assay for transposase accessible chromatin) sequencing and RNA sequencing (RNA-seq), spatial snATAC-seq and RNA-seq, and in situ sequencing and hybridization mapping of transcriptomes at molecular resolution to spatially reconstruct the joint epigenomic and transcriptomic regulatory landscape. Paired analyses unraveled intricate tumor-like gene expression and transcription factor motif programs potentially sustaining the placenta in a hostile uterine environment; further investigation of gene-linked cis-regulatory elements revealed heightened regulatory complexity that may govern trophoblast differentiation and placental disease risk. Complementary spatial mapping techniques decoded these programs within the placental villous core and extravillous trophoblast cell column architecture while simultaneously revealing niche-establishing transcriptional elements and cell-cell communication. Finally, we computationally imputed genome-wide, multiomic single-cell profiles and spatially characterized the placental chromatin accessibility landscape. This spatially resolved, single-cell multiomic framework of the first trimester human placenta serves as a blueprint for future studies on early placental development and pregnancy.

Decoding the molecular pathways governing trophoblast migration and placental development; a literature review

Placental development is a multifaceted process critical for a fruitful pregnancy, reinforced by a complex network of molecular pathways that synchronize trophoblast migration, differentiation, and overall placental function. This review provides an in-depth analysis of the key signaling pathways, such as Wnt, Notch, TGF-β, and VEGF, which play fundamental roles in trophoblast proliferation, invasion, and the complicated process of placental vascular development. For instance, the Wnt signaling pathway is essential to balance trophoblast stem cell proliferation and differentiation, while Notch signaling stimulates cell fate decisions and invasive behavior. TGF-β signaling plays a critical role in trophoblast invasion and differentiation, predominantly in response to the low oxygen environment of early pregnancy, regulated by hypoxia-inducible factors (HIFs). These factors promote trophoblast adaptation, ensure proper placental attachment and vascularization, and facilitate adequate fetal-maternal exchange. Further, we explore the epigenetic and post-transcriptional regulatory mechanisms that regulate trophoblast function, including DNA methylation and the contribution of non-coding RNAs, which contribute to the fine-tuning of gene expression during placental development. Dysregulation of these pathways is associated with severe pregnancy complications, such as preeclampsia, intrauterine growth restriction, and recurrent miscarriage, emphasizing the critical need for targeted therapeutic strategies. Finally, emerging technologies like trophoblast organoids, single-cell RNA sequencing, and placenta-on-chip models are discussed as innovative tools that hold promise for advancing our understanding of placental biology and developing novel interventions to improve pregnancy outcomes. This review emphasizes the importance of understanding these molecular mechanisms to better address placental dysfunctions and associated pregnancy disorders.

Decreased RSPO3 and β-Catenin in Preeclampsia: Correlation with Blood Pressure and Pregnancy Outcomes

BACKGROUND This study aimed to investigate the expression of RSPO3 and ß-catenin in preeclampsia and the relationship between RSPO3 and b-catenin levels and maternal-fetal outcomes. MATERIAL AND METHODS We enrolled 60 pregnant women with preeclampsia and 60 pregnant women without preeclampsia. We collected peripheral blood from the patients upon admission; placenta and cord blood were collected after delivery. The expression of RSPO3 and ß-catenin in maternal blood, cord blood, and placenta was measured. We used the Spearman method to examine the correlations between clinical characteristics and RSPO3. Logistic regression modeling was used to identify the independent risk factors for preeclampsia. RESULTS RSPO3 and ß-catenin levels were decreased in the peripheral blood, cord blood, and placentas of women with preeclampsia, with significant differences (P<0.05). The preeclampsia group had more adverse pregnancy outcomes. RSPO3 level of the preeclampsia group was negatively correlated with systolic blood pressure (r=-0.4654, P<0.001) and diastolic blood pressure (r=-0.4617, P<0.001) in cord blood, and systolic blood pressure (r=-0.5373, P<0.05) and diastolic blood pressure (r=-0.4898, P<0.05) in maternal blood. CONCLUSIONS RSPO3 and ß-catenin were decreased in preeclampsia, RSPO3 was negatively correlated with blood pressure, and RSPO3 could be a risk factor for the development of preeclampsia.

NOTUM-mediated WNT silencing drives extravillous trophoblast cell lineage development

Trophoblast stem (TS) cells have the unique capacity to differentiate into specialized cell types, including extravillous trophoblast (EVT) cells. EVT cells invade into and transform the uterus where they act to remodel the vasculature facilitating the redirection of maternal nutrients to the developing fetus. Disruptions in EVT cell development and function are at the core of pregnancy-related disease. WNT-activated signal transduction is a conserved regulator of morphogenesis of many organ systems, including the placenta. In human TS cells, activation of canonical WNT signaling is critical for maintenance of the TS cell stem state and its downregulation accompanies EVT cell differentiation. We show that aberrant WNT signaling undermines EVT cell differentiation. Notum, palmitoleoyl-protein carboxylesterase (NOTUM), a negative regulator of canonical WNT signaling, was prominently expressed in first-trimester EVT cells developing in situ and up-regulated in EVT cells derived from human TS cells. Furthermore, NOTUM was required for optimal human TS cell differentiation to EVT cells. Activation of NOTUM in EVT cells is driven, at least in part, by endothelial Per-Arnt-Sim (PAS) domain 1 (also called hypoxia-inducible factor 2 alpha). Collectively, our findings indicate that canonical Wingless-related integration site (WNT) signaling is essential for maintenance of human trophoblast cell stemness and regulation of human TS cell differentiation. Downregulation of canonical WNT signaling via the actions of NOTUM is required for optimal EVT cell differentiation.

SIRT5 suppresses the trophoblast cell proliferation, invasion, and migration to promote preeclampsia via desuccinylating HOXB3

PURPOSE

Preeclampsia (PE) is a pregnancy-specific syndrome with increasing maternal and perinatal morbidity and mortality. Succinylation, a post-translational modification event, has been found in various diseases. However, the role of succinylation in PE has not been explored. This study aimed to investigate the effect of succinylation on PE and the underlying mechanisms.

METHODS

Thirty-two PE patients and 32 normal pregnancy volunteers were recruited. Human extravasated trophoblast cells (HTR-8/SVneo) were used in in vitro study. RT-qPCR was performed to detect the expression of succinylation-related mRNAs. The cell proliferation, invasion, and migration were assessed using cell counting kit-8, ethynyldeoxyuridine, transwell, and wound healing assays. Co-immunoprecipitation and dual-luciferase reporter assays were performed to analyze the interaction between sirtuin (SIRT)5 and homeobox box 3 (HOXB3).

RESULTS

SIRT5 was increased in the placental tissues of PE patients. SIRT5 inhibition increased cell proliferation, invasion, and migration in HTR-8/SVneo cells. Mechanistic investigations indicated that HOXB3 was a downstream regulatory target of SIRT5-mediated desuccinylation. Rescue experiments further verified that silencing of HOXB3 inhibited cell proliferation, invasion, and migration. Additionally, HOXB3 deficiency reversed the activation of the Notch and β-catenin signaling pathway induced by SIRT5 inhibition.

CONCLUSION

SIRT5 inhibited the trophoblast cell proliferation, invasion, and migration to promote PE through suppressing Notch and β-catenin signaling pathway activation via desuccinylating HOXB3.

Generation and Characterization of Induced Pluripotent Stem Cells Carrying An ASXL1 Mutation

Additional sex combs-like 1 (ASXL1) is an epigenetic modulator frequently mutated in myeloid malignancies, generally associated with poor prognosis. Current models for ASXL1-mutated diseases are mainly based on the complete deletion of Asxl1 or overexpression of C-terminal truncations in mice models. However, these models cannot fully recapitulate the pathogenesis of myeloid malignancies. Patient-derived induced pluripotent stem cells (iPSCs) provide valuable disease models that allow us to understand disease-related molecular pathways and develop novel targeted therapies. Here, we generated iPSCs from a patient with myeloproliferative neoplasm carrying a heterozygous ASXL1 mutation. The iPSCs we generated exhibited the morphology of pluripotent cells, highly expressed pluripotent markers, excellent differentiation potency in vivo, and normal karyotype. Subsequently, iPSCs with or without ASXL1 mutation were induced to differentiate into hematopoietic stem/progenitor cells, and we found that ASXL1 mutation led to myeloid-biased output and impaired erythroid differentiation. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses showed that terms related to embryonic development, myeloid differentiation, and immune- and neural-related processes were most enriched in the differentially expressed genes. Western blot demonstrated that the global level of H2AK119ub was significantly decreased when mutant ASXL1 was present. Chromatin Immunoprecipitation Sequencing showed that most genes associated with stem cell maintenance were upregulated, whereas occupancies of H2AK119ub around these genes were significantly decreased. Thus, the iPSC model carrying ASXL1 mutation could serve as a potential tool to study the pathogenesis of myeloid malignancies and to screen targeted therapy for patients.

Identification and RT-qPCR Validation of Biomarkers Based on Butyrate Metabolism-Related Genes to Predict Recurrent Miscarriage

Purpose

To date, the cause of recurrent miscarriage (RM) in at least 50% of patients remains unknown. However, no study has explored the correlation between butyrate metabolism-related genes (BMRGs) and RM.

Methods

RM-related datasets (GSE165004, GSE111974, GSE73025, and GSE179996) were obtained from the Gene Expression Omnibus (GEO) database. First, 595 differentially expressed genes (DEGs) were identified between the RM and control samples in GSE165004. Subsequently, 213 differentially expressed BMRGs (DE-BMRGs) were identified by considering the intersection of DEGs with BMRGs. The protein-protein interaction (PPI)network of DE-BMRGs contained 156 nodes and 250 edges, and a key module was obtained. In total, four biomarkers (ACTR2, ANXA2, PFN1, and OAS1) were acquired through least absolute shrinkage and selection operator (LASSO), support vector machine-recursive feature elimination (SVM-RFE), and random forest (RF). Immune analysis revealed two immune cells and three immune-related gene sets that were significantly different between the RM and control groups, namely, T helper cells, regulatory T cells (Treg), MHC class I, parainflammation, and type I IFN response. In addition, a TF-mRNA network based on the top 100 nodes ranked in the order of connectivity was created, including 100 nodes and 253 edges, such as MTERF2-ACTR2, NKX23-PFN1, STAT1-OAS1, and SP100-ANXA2.

Results

Finally, 3 drugs (withaferin A, N-ethylmaleimide, and etoposide) were predicted to interact with 2 biomarkers (ANXA2 and ACTR2). Eventually, ANXA2 and OAS1 were significantly downregulated, and PFN1 was markedly overexpressed in the RM group, as determined by reverse transcription quantitative polymerase chain reaction (RT-qPCR).

Conclusion

Our findings authenticated four butyrate metabolism-related biomarkers for the diagnosis of RM, providing a scientific reference for further studies on RM treatment.

Placental Tissue Calcification and Its Molecular Pathways in Female Patients with Late-Onset Preeclampsia

Preeclampsia (PE) is a complex multisystem disease characterized by hypertension of sudden onset (>20 weeks' gestation) coupled with the presence of at least one additional complication, such as proteinuria, maternal organ dysfunction, or uteroplacental dysfunction. Hypertensive states during pregnancy carry life-threatening risks for both mother and baby. The pathogenesis of PE develops due to a dysfunctional placenta with aberrant architecture that releases factors contributing to endothelial dysfunction, an antiangiogenic state, increased oxidative stress, and maternal inflammatory responses. Previous studies have shown a correlation between grade 3 placental calcifications and an elevated risk of developing PE at term. However, little is known about the molecular pathways leading to placental calcification. In this work, we studied the gene and protein expression of c-Jun N-terminal kinase (JNK), Runt-related transcription factor 2 (RUNX2), osteocalcin (OSC), osteopontin (OSP), pigment epithelium-derived factor (PEDF), MSX-2/HOX8, SOX-9, WNT-1, and β-catenin in placental tissue from women with late-onset PE (LO-PE). In addition, we employed von Kossa staining to detect mineral deposits in placental tissues. Our results show a significant increase of all these components in placentas from women with LO-PE. Therefore, our study suggests that LO-PE may be associated with the activation of molecular pathways of placental calcification. These results could be the starting point for future research to describe the molecular mechanisms that promote placental calcification in PE and the development of therapeutic strategies directed against it.

NOTUM-MEDIATED WNT SILENCING DRIVES EXTRAVILLOUS TROPHOBLAST CELL LINEAGE DEVELOPMENT

Trophoblast stem (TS) cells have the unique capacity to differentiate into specialized cell types, including extravillous trophoblast (EVT) cells. EVT cells invade into and transform the uterus where they act to remodel the vasculature facilitating the redirection of maternal nutrients to the developing fetus. Disruptions in EVT cell development and function are at the core of pregnancy-related disease. WNT-activated signal transduction is a conserved regulator of morphogenesis of many organ systems, including the placenta. In human TS cells, activation of canonical WNT signaling is critical for maintenance of the TS cell stem state and its downregulation accompanies EVT cell differentiation. We show that aberrant WNT signaling undermines EVT cell differentiation. Notum, palmitoleoyl-protein carboxylesterase (NOTUM), a negative regulator of canonical WNT signaling, was prominently expressed in first trimester EVT cells developing in situ and upregulated in EVT cells derived from human TS cells. Furthermore, NOTUM was required for optimal human TS cell differentiation to EVT cells. Activation of NOTUM in EVT cells is driven, at least in part, by endothelial PAS domain 1 (also called hypoxia-inducible factor 2 alpha). Collectively, our findings indicate that canonical WNT signaling is essential for maintenance of human trophoblast cell stemness and regulation of human TS cell differentiation. Downregulation of canonical WNT signaling via the actions of NOTUM is required for optimal EVT cell differentiation.

Embryonic Lethal Phenotyping to Identify Candidate Genes Related with Birth Defects

Congenital birth defects contribute significantly to preterm birth, stillbirth, perinatal death, infant mortality, and adult disability. As a first step to exploring the mechanisms underlying this major clinical challenge, we analyzed the embryonic phenotypes of lethal strains generated by random mutagenesis. In this study, we report the gross embryonic and perinatal phenotypes of 55 lethal strains randomly picked from a collection of mutants that carry piggyBac (PB) transposon inserts. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses suggested most of the analyzed mutations hit genes involved in heart and nervous development, or in Notch and Wnt signaling. Among them, 12 loci are known to be associated with human diseases. We confirmed 53 strains as embryonic or perinatal lethal, while others were subviable. Gross morphological phenotypes such as body size abnormality (29/55, 52.73%), growth or developmental delay (35/55, 63.64%), brain defects (9/55, 16.36%), vascular/heart development (31/55, 56.36%), and other structural defects (9/55, 16.36%) could be easily observed in the mutants, while three strains showed phenotypes similar to those of human patients. Furthermore, we detected body weight or body composition alterations in the heterozygotes of eight strains. One of them was the TGF-β signaling gene Smad2. The heterozygotes showed increased energy expenditure and a lower fat-to-body weight ratio compared to wild-type mice. This study provided new insights into mammalian embryonic development and will help understand the pathology of congenital birth defects in humans. In addition, it expanded our understanding of the etiology of obesity.

TGFβ signalling: a nexus between inflammation, placental health and preeclampsia throughout pregnancy

BACKGROUND

The placenta is a unique and pivotal organ in reproduction, controlling crucial growth and cell differentiation processes that ensure a successful pregnancy. Placental development is a tightly regulated and dynamic process, in which the transforming growth factor beta (TGFβ) superfamily plays a central role. This family of pleiotropic growth factors is heavily involved in regulating various aspects of reproductive biology, particularly in trophoblast differentiation during the first trimester of pregnancy. TGFβ signalling precisely regulates trophoblast invasion and the cell transition from cytotrophoblasts to extravillous trophoblasts, which is an epithelial-to-mesenchymal transition-like process. Later in pregnancy, TGFβ signalling ensures proper vascularization and angiogenesis in placental endothelial cells. Beyond its role in trophoblasts and endothelial cells, TGFβ signalling contributes to the polarization and function of placental and decidual macrophages by promoting maternal tolerance of the semi-allogeneic foetus. Disturbances in early placental development have been associated with several pregnancy complications, including preeclampsia (PE) which is one of the severe complications. Emerging evidence suggests that TGFβ is involved in the pathogenesis of PE, thereby offering a potential target for intervention in the human placenta.

OBJECTIVE AND RATIONALE

This comprehensive review aims to explore and elucidate the roles of the major members of the TGFβ superfamily, including TGFβs, bone morphogenetic proteins (BMPs), activins, inhibins, nodals, and growth differentiation factors (GDFs), in the context of placental development and function. The review focusses on their interactions within the major cell types of the placenta, namely trophoblasts, endothelial cells, and immune cells, in both normal pregnancies and pregnancies complicated by PE throughout pregnancy.

SEARCH METHODS

A literature search was carried out using PubMed and Google Scholar, searching terms: 'TGF signalling preeclampsia', 'pregnancy TGF signalling', 'preeclampsia tgfβ', 'preeclampsia bmp', 'preeclampsia gdf', 'preeclampsia activin', 'endoglin preeclampsia', 'endoglin pregnancy', 'tgfβ signalling pregnancy', 'bmp signalling pregnancy', 'gdf signalling pregnancy', 'activin signalling pregnancy', 'Hofbauer cell tgfβ signalling', 'placental macrophages tgfβ', 'endothelial cells tgfβ', 'endothelium tgfβ signalling', 'trophoblast invasion tgfβ signalling', 'trophoblast invasion Smad', 'trophoblast invasion bmp', 'trophoblast invasion tgfβ', 'tgfβ preeclampsia', 'tgfβ placental development', 'TGFβ placental function', 'endothelial dysfunction preeclampsia tgfβ signalling', 'vascular remodelling placenta TGFβ', 'inflammation pregnancy tgfβ', 'immune response pregnancy tgfβ', 'immune tolerance pregnancy tgfβ', 'TGFβ pregnancy NK cells', 'bmp pregnancy NK cells', 'bmp pregnancy tregs', 'tgfβ pregnancy tregs', 'TGFβ placenta NK cells', 'TGFβ placenta tregs', 'NK cells preeclampsia', 'Tregs preeclampsia'. Only articles published in English until 2023 were used.

OUTCOMES

A comprehensive understanding of TGFβ signalling and its role in regulating interconnected cell functions of the main placental cell types provides valuable insights into the processes essential for successful placental development and growth of the foetus during pregnancy. By orchestrating trophoblast invasion, vascularization, immune tolerance, and tissue remodelling, TGFβ ligands contribute to the proper functioning of a healthy maternal-foetal interface. However, dysregulation of TGFβ signalling has been implicated in the pathogenesis of PE, where the shallow trophoblast invasion, defective vascular remodelling, decreased uteroplacental perfusion, and endothelial cell and immune dysfunction observed in PE, are all affected by an altered TGFβ signalling.

WIDER IMPLICATIONS

The dysregulation of TGFβ signalling in PE has important implications for research and clinical practice. Further investigation is required to understand the underlying mechanisms, including the role of different ligands and their regulation under pathophysiological conditions, in order to discover new therapeutic targets. Distinguishing between clinically manifested subtypes of PE and studying TGFβ signalling in different placental cell types holistically is an important first step. To put this knowledge into practice, pre-clinical animal models combined with new technologies are needed. This may also lead to improved human research models and identify potential therapeutic targets, ultimately improving outcomes for affected pregnancies and reducing the burden of PE.

Overexpressed Trophoblast Glycoprotein Contributes to Preeclampsia Development by Inducing Abnormal Trophoblast Migration and Invasion Toward the Uterine Spiral Artery

BACKGROUND

Preeclampsia is a significant pregnancy disorder with an unknown cause, mainly attributed to impaired spiral arterial remodeling.

METHODS

Using RNA sequencing, we identified key genes in placental tissues from healthy individuals and preeclampsia patients. Placenta and plasma samples from pregnant women were collected to detect the expression of TPBG (trophoblast glycoprotein). Pregnant rats were injected with TPBG-carrying adenovirus to detect preeclamptic features. HTR-8/SVneo cells transfected with a TPBG overexpression lentiviral vector were used in cell function experiments. The downstream molecular mechanisms of TPBG were explored using RNA sequencing and single-cell RNA sequencing data. TPBG expression was knocked down in the lipopolysaccharide-induced preeclampsia-like rat model to rescue the preeclampsia features. We also assessed TPBG's potential as an early preeclampsia predictor using clinical plasma samples.

RESULTS

TPBG emerged as a crucial differentially expressed gene, expressed specifically in syncytiotrophoblasts and extravillous trophoblasts. Subsequently, we established a rat model with preeclampsia-like phenotypes by intravenously injecting TPBG-expressing adenoviruses, observing impaired spiral arterial remodeling, thus indicating a causal correlation between TPBG overexpression and preeclampsia. Studies with HTR-8/SVneo cells, chorionic villous explants, and transwell assays showed TPBG overexpression disrupts trophoblast/extravillous trophoblast migration/invasion and chemotaxis. Notably, TPBG knockdown alleviated the lipopolysaccharide-induced preeclampsia-like rat model. We enhanced preeclampsia risk prediction in early gestation by combining TPBG expression with established clinical predictors.

CONCLUSIONS

These findings are the first to show that TPBG overexpression contributes to preeclampsia development by affecting uterine spiral artery remodeling. We propose TPBG levels in maternal blood as a predictor of preeclampsia risk. The proposed mechanism by which TPBG overexpression contributes to the occurrence of preeclampsia via its disruptive effect on trophoblast and extravillous trophoblast migration/invasion on uterine spiral artery remodeling, thereby increasing the risk of preeclampsia.

Potential molecular mechanisms and clinical implications of piRNAs in preeclampsia: a review

Preeclampsia is a multisystem progressive condition and is one of the most serious complications of pregnancy. Owing to its unclear pathogenesis, there are no precise and effective therapeutic targets for preeclampsia, and the only available treatment strategy is to terminate the pregnancy and eliminate the clinical symptoms. In recent years, non-coding RNAs have become a hotspot in preeclampsia research and have shown promise as effective biomarkers for the early diagnosis of preeclampsia over conventional biochemical markers. PIWI-interacting RNAs, novel small non-coding RNA that interact with PIWI proteins, are involved in the pathogenesis of various diseases at the transcriptional or post-transcriptional level. However, the mechanisms underlying the role of PIWI-interacting RNAs in the pathogenesis of preeclampsia remain unclear. In this review, we discuss the findings of existing studies on PIWI-interacting RNA biogenesis, functions, and their possible roles in preeclampsia, providing novel insights into the potential application of PIWI-interacting RNAs in the early diagnosis and clinical treatment of preeclampsia.

Association between dietary soy prevention of fetal alcohol spectrum disorder and normalization of placental insulin and insulin-like growth factor signaling networks and downstream effector molecule expression

Chronic prenatal alcohol exposure causes fetal alcohol spectrum disorder (FASD), often associated with impaired placentation and intrauterine growth restriction. Ethanol's inhibition of insulin and insulin-like growth factor Type 1 (IGF-1) signaling compromises trophoblastic cell motility and maternal vascular transformation at the implantation site. Previous studies have demonstrated that dietary soy effectively normalizes placentation and fetal growth in an experimental model of FASD. The studies were extended to better understand the mechanisms underlying soy's beneficial effects. Pregnant Long Evans rats were pair-fed with isocaloric liquid diets containing either 0% or 36% caloric ethanol from gestation day (GD) 6. The protein source in the diets consisted of either casein (standard and control) or soy isolate. On GD19, placentas were harvested to measure mRNA levels corresponding to major components of the insulin/IGF-1 pathway, as well as aspartyl-asparaginyl-β-hydroxylase (ASPH), Notch, and HES, which play critical roles in placentation. Chronic gestational ethanol exposure in rats fed diets containing casein significantly reduced the expression of insulin, insulin receptor, Igf1, IGF-1 receptor (Igf1r), insulin receptor substrate Type 1 (Irs1), Irs2, Asph, and Hes1. In addition, ethanol significantly decreased ASPH protein expression. Dietary soy mitigated most of these effects and further enhanced signaling by upregulating Igf2, Igf2r, Irs1, Irs2, Irs4, Notch, and Hes1 in rats chronically exposed to ethanol relative to corresponding control samples. The protective effects of dietary soy in FASD act at the mRNA level and positively impact pathways imperative for normal placentation and fetal development. Gestational dietary soy may provide an effective means of preventing FASD in vulnerable populations.

Ursolic Acid Alleviates Mitotic Catastrophe in Podocyte by Inhibiting Autophagic P62 Accumulation in Diabetic Nephropathy

The glomerular podocyte, a terminally differentiated cell, is crucial for the integrity of the glomerular filtration barrier. The re-entry of podocytes into the mitotic phase results in injuries or death, known as mitotic catastrophe (MC), which significantly contributes to the progression of diabetic nephropathy (DN). Furthermore, P62-mediated autophagic flux has been shown to regulate DN-induced podocyte injury. Although previous studies, including ours, have demonstrated that ursolic acid (UA) mitigates podocyte injury by enhancing autophagy under high glucose conditions, the protective functions and potential regulatory mechanisms of UA against DN have not been fully elucidated. For aiming to investigate the regulatory mechanism of podocyte injuries in DN progression, and the protective function of UA treatment against DN progression, we utilized db/db mice and high glucose (HG)-induced podocyte models in vivo and in vitro, with or without UA administration. Our findings indicate that UA treatment reduced DN progression by improving biochemical indices. P62 accumulation led to Murine Double Minute gene 2 (MDM2)-regulated MC in podocytes during DN, which was ameliorated by UA through enhanced P62-mediated autophagy. Additionally, the overexpression of NF-κB p65 or TNF-α abolished the protective effects of UA both in vivo and in vitro. Overall, our results provide strong evidence that UA could be a potential therapeutic agent for DN, regulated by inhibiting podocyte MC through the NF-κB/MDM2/Notch1 pathway by targeting autophagic-P62 accumulation.

GATA3 and TGF-β in normal placenta and pre-eclampsia

GATA3 plays critical roles in the development and function of various tissues and organs throughout the body. Likewise, TGF-β signaling is critical for placental development and can interact with GATA3. We aimed to investigate the involvement of the multifunctional cytokine and transcription factor in trophoblast development. By using immunohistochemistry, we evaluated the localization and expression level of GATA3 and TGF-β in placentas at term of normal pregnancy and with pre-eclampsia. Up-regulation of both GATA3 and TGF-β was observed in pathological placentas, with localization in the villus epithelium (syncytiotrophoblast) stroma and decidua. Our data show altered expression of TGF-β and GATA3, which downstream could lead to a cascade of events that negatively influence trophoblast development and contribute to the pathogenesis of pre-eclampsia.

Notch Signaling: An Emerging Paradigm in the Pathogenesis of Reproductive Disorders and Diverse Pathological Conditions

The highly conserved Notch pathway, a pillar of juxtacrine signaling, orchestrates intricate intercellular communication, governing diverse developmental and homeostatic processes through a tightly regulated cascade of proteolytic cleavages. This pathway, culminating in the migration of the Notch intracellular domain (NICD) to the nucleus and the subsequent activation of downstream target genes, exerts a profound influence on a plethora of molecular processes, including cell cycle progression, lineage specification, cell-cell adhesion, and fate determination. Accumulating evidence underscores the pivotal role of Notch dysregulation, encompassing both gain and loss-of-function mutations, in the pathogenesis of numerous human diseases. This review delves deep into the multifaceted roles of Notch signaling in cellular dynamics, encompassing proliferation, differentiation, polarity maintenance, epithelial-mesenchymal transition (EMT), tissue regeneration/remodeling, and its intricate interplay with other signaling pathways. We then focus on the emerging landscape of Notch aberrations in gynecological pathologies predisposing individuals to infertility. By highlighting the exquisite conservation of Notch signaling in Drosophila and its power as a model organism, we pave the way for further dissection of disease mechanisms and potential therapeutic interventions through targeted modulation of this master regulatory pathway.

Exosomal encapsulation of miR-3198 promotes proliferation and migration of trophoblasts in preeclampsia

PURPOSE

Preeclampsia (PE) is a vascular remodeling disorder cloesly linked to trophoblast dysfunction, involving defects in their proliferation, migration, and apoptosis. Maternal exosomal microRNAs (miRNAs) have been reported to play pivotal roles in the development of PE. However, the mechanism underlying the role of maternal exosomes in trophoblast dysfunction regarding the development of PE is poorly understood.

METHODS

Plasma exosomes from maternal peripheral blood were collected from pregnant women with PE and from those with normal pregnancy. Bioinformatics analysis was used to identify significantly differentially expressed miRNAs under these two conditions. The expression of the miR-3198 gene in plasma exosomes was detected using quantitative real-time polymerase chain reaction. Dual luciferase reporter assay was used to confirm binding of miR-3198 and 3'UTR region of WNT3. Cell proliferation was examined using the Cell Count Kit-8 and EdU assays, and flow cytometry was performed to detect apoptosis and cell cycle. Changes in cell migration were examined using transwell and scratch assays.

RESULTS

Patients with PE showed decreased expression of plasma-derived exosomal miR-3198. The proliferation and migration abilities of HTR-8/SVneo and primary human trophoblast cells were both improved when cocultured with miR-3198-rich exosomes. Exposure to miR-3198-enriched exosomes facilitated cell cycle progression but reduced apoptosis in HTR-8/SVneo cells. Notably, overexpression of miR-3198 partially prevented the inhibitory effects of WNT3 on proliferation and migration in HTR-8/SVneo cells.

CONCLUSION

Exosomal miR-3198 in the maternal peripheral blood may regulate the biological functions of trophoblasts by targeting WNT3 and influence the development of diseases of placental origin.

Maternal exposure to beta-Cypermethrin disrupts placental development by dysfunction of trophoblast cells from oxidative stress

As a broad-spectrum and efficient insecticide, beta-Cypermethrin (β-CYP) poses a health risk to pregnancy. It matters the mechanisms of maternal exposure to β-CYP for impacting reproductive health. The placenta, a transient organ pivotal for maternal-fetal communication during pregnancy, plays a crucial role in embryonic development. The effect of β-CYP exposure on the placenta and its underlying molecular mechanisms remain obscure. The objective of this study was to investigate the effect of β-CYP exposure on placental development and the function of trophoblast, as well as the underlying mechanisms through CD-1 mouse model (1, 10, 20 mg/kg.bw) and in vitro HTR-8/SVneo cell model (12.5, 25, 50, 100 μM). We found slower weight gain and reduced uterine wet weight in pregnant mice with maternal exposure to β-CYP during pregnancy, as well as adverse pregnancy outcomes such as uterine bleeding and embryo resorption. The abnormal placental development in response to β-CYP was noticed, including imbalanced placental structure and disrupted labyrinthine vascular development. Trophoblasts, pivotal in placental development and vascular remodeling, displayed abnormal differentiation under β-CYP exposure. This aberration was characterized by thickened trophoblast layers in the labyrinthine zone, accompanied by mitochondrial and endoplasmic reticulum swelling within trophoblasts. Further researches on human chorionic trophoblast cell lines revealed that β-CYP exposure induced apoptosis in HTR-8/SVneo cells. This induction resulted in a notable decrease in migration and invasion abilities, coupled with oxidative stress and the inhibition of the Notch signaling pathway. N-acetylcysteine (an antioxidant) partially restored the impaired Notch signaling pathway in HTR-8/SVneo cells, and mitigated cellular functional damage attributed to β-CYP exposure. Collectively, exposure to β-CYP induced oxidative stress and then led to inhibition of the Notch signaling pathway and dysfunction of trophoblast cells, ultimately resulted in abnormal placenta and pregnancy. These findings indicate Reactive Oxygen Species as potential intervention targets to mitigate β-CYP toxicity. The comprehensive elucidation contributes to our understanding of β-CYP biosafety and offers an experimental basis for preventing and managing its reproductive toxicity.

Effects of Regulating Hippo and Wnt on the Development and Fate Differentiation of Bovine Embryo

The improvement of in vitro embryo development is a gateway to enhance the output of assisted reproductive technologies. The Wnt and Hippo signaling pathways are crucial for the early development of bovine embryos. This study investigated the development of bovine embryos under the influence of a Hippo signaling agonist (LPA) and a Wnt signaling inhibitor (DKK1). In this current study, embryos produced in vitro were cultured in media supplemented with LPA and DKK1. We comprehensively analyzed the impact of LPA and DKK1 on various developmental parameters of the bovine embryo, such as blastocyst formation, differential cell counts, YAP fluorescence intensity and apoptosis rate. Furthermore, single-cell RNA sequencing (scRNA-seq) was employed to elucidate the in vitro embryonic development. Our results revealed that LPA and DKK1 improved the blastocyst developmental potential, total cells, trophectoderm (TE) cells and YAP fluorescence intensity and decreased the apoptosis rate of bovine embryos. A total of 1203 genes exhibited differential expression between the control and LPA/DKK1-treated (LD) groups, with 577 genes upregulated and 626 genes downregulated. KEGG pathway analysis revealed significant enrichment of differentially expressed genes (DEGs) associated with TGF-beta signaling, Wnt signaling, apoptosis, Hippo signaling and other critical developmental pathways. Our study shows the role of LPA and DKK1 in embryonic differentiation and embryo establishment of pregnancy. These findings should be helpful for further unraveling the precise contributions of the Hippo and Wnt pathways in bovine trophoblast formation, thus advancing our comprehension of early bovine embryo development.

Single-cell assessment of primary and stem cell-derived human trophoblast organoids as placenta-modeling platforms

Human trophoblast stem cells (hTSCs) and related trophoblast organoids are state-of-the-art culture systems that facilitate the study of trophoblast development and human placentation. Using single-cell transcriptomics, we evaluate how organoids derived from freshly isolated first-trimester trophoblasts or from established hTSC cell lines reproduce developmental cell trajectories and transcriptional regulatory processes defined in vivo. Although organoids from primary trophoblasts and hTSCs overall model trophoblast differentiation with accuracy, specific features related to trophoblast composition, trophoblast differentiation, and transcriptional drivers of trophoblast development show levels of misalignment. This is best illustrated by the identification of an expanded progenitor state in stem cell-derived organoids that is nearly absent in vivo and transcriptionally shares both villous cytotrophoblast and extravillous trophoblast characteristics. Together, this work provides a comprehensive resource that identifies strengths and limitations of current trophoblast organoid platforms.

Morphogenesis of fungiform papillae in developing miniature pigs

Objective

Fungiform papillae contain taste buds and play a critical role in mastication and the gustatory system. In this study, we report a series of sequential observations of organogenesis of fungiform papillae in miniature pigs, as well as changes in the expression of BMP2, BMP4, Wnt5a, Sox2, and Notch1 signaling pathway components.

Design

In this study, we investigated the spatiotemporal expression patterns of BMP, Wnt, Sox2 and Notch in the fungiform papillae of miniature pigs at the bud stage (E40), cap stage (E50) and bell stage (E60). Pregnant miniature pigs were obtained, and the samples were processed for histological staining. Immunohistochemistry and real-time PCR were used to detect the mRNA and protein expression levels of BMP2, BMP4, Wnt5a, Sox2, and Notch1.

Results

At E40, fungiform papillae were present on the anterior two-thirds of the tongue in a specific array and pattern. The fungiform papillae were enlarged and basically developed at E50 and were largest at the earlier stage (E60). Most of the BMP2 was concentrated in the epithelial layer and the connective tissue core of the fungal papilloma and gradually accumulated from E40-E60. BMP-4 was weakly expressed in the fungiform papillae epithelia, but BMP-4-positive cells were also observed in the developing tongue muscle at E50 and E60. Wnt5a-positive cells were observed in the fungiform papillae epithelia and developing tongue muscle at all three time points. Sox2-positive cells were observed only in fungiform papillae epithelial cells, and Notch1-positive cells could not be detected.

Conclusions

This study provides primary data regarding the morphogenesis and expression of developmental signals in the fungiform papillae of miniature pigs, establishing a foundation for further research in both this model and humans.

The transcriptional regulatory network modulating human trophoblast stem cells to extravillous trophoblast differentiation

During human pregnancy, extravillous trophoblasts play crucial roles in placental invasion into the maternal decidua and spiral artery remodeling. However, regulatory factors and their action mechanisms modulating human extravillous trophoblast specification have been unknown. By analyzing dynamic changes in transcriptome and enhancer profile during human trophoblast stem cell to extravillous trophoblast differentiation, we define stage-specific regulators, including an early-stage transcription factor, TFAP2C, and multiple late-stage transcription factors. Loss-of-function studies confirm the requirement of all transcription factors identified for adequate differentiation, and we reveal that the dynamic changes in the levels of TFAP2C are essential. Notably, TFAP2C pre-occupies the regulatory elements of the inactive extravillous trophoblast-active genes during the early stage of differentiation, and the late-stage transcription factors directly activate extravillous trophoblast-active genes, including themselves as differentiation further progresses, suggesting sequential actions of transcription factors assuring differentiation. Our results reveal stage-specific transcription factors and their inter-connected regulatory mechanisms modulating extravillous trophoblast differentiation, providing a framework for understanding early human placentation and placenta-related complications.

Chemical mixture that targets the epidermal growth factor pathway impairs human trophoblast cell functions

Pregnant women are exposed to complex chemical mixtures, many of which reach the placenta. Some of these chemicals interfere with epidermal growth factor receptor (EGFR) activation, a receptor tyrosine kinase that modulates several placenta cell functions. We hypothesized that a mixture of chemicals (Chem-Mix) known to reduce EGFR activation (polychlorinated biphenyl (PCB)-126, PCB-153, atrazine, trans-nonachlor, niclosamide, and bisphenol S) would interfere with EGFR-mediated trophoblast cell functions. To test this, we determined the chemicals' EGFR binding ability, EGFR and downstream effectors activation, and trophoblast functions (proliferation, invasion, and endovascular differentiation) known to be regulated by EGFR in extravillous trophoblasts (EVTs). The Chem-Mix competed with EGF for EGFR binding, however only PCB-153, niclosamide, trans-nonachlor, and BPS competed for binding as single chemicals. The effects of the Chem-Mix on EGFR phosphorylation were tested by exposing the placental EVT cell line, HTR-8/SVneo to control (0.1% DMSO), Chem-Mix (1, 10, or 100 ng/ml), EGF (30 ng/ml), or Chem-Mix + EGF. The Chem-Mix - but not the individual chemicals - reduced EGF-mediated EGFR phosphorylation in a dose dependent manner, while no effect was observed in its downstream effectors (AKT and STAT3). None of the individual chemicals affected EVT cell invasion, but the Chem-Mix reduced EVT cell invasion independent of EGF. In support of previous studies that have explored chemicals targeting a specific pathway (estrogen/androgen receptor), current findings indicate that exposure to a chemical mixture that targets the EGFR pathway can result in a greater impact compared to individual chemicals in the context of placental cell functions.

The role of circular RNA in preeclampsia: From pathophysiological mechanism to clinical application

Preeclampsia (PE) is a common pregnancy-induced hypertension disorder that poses a significant threat to the health of pregnant women and fetuses, and has become a leading cause of maternal, fetal, and neonatal mortality. Currently, the therapy strategy for PE is mainly prevention management and symptomatic treatment, and only delivery can completely terminate PE. Therefore, a deeper understanding of the pathogenesis of PE is needed to make treatment and prevention more effective and targeted. With the deepening of molecular etiology research, circular RNAs (circRNAs) have been found to be widely involved in various processes of PE pathogenesis. As a kind of RNA with a special "head to tail" loop structure, the characteristics of circRNAs enable them to play diverse roles in the pathophysiology of PE, and can also serve as ideal biomarkers for early prediction and monitoring progression of PE. In this review, we summarized the latest research on PE-related circRNAs, trying to elucidate the unique or shared roles of circRNAs in various pathophysiological mechanisms of PE, aiming to provide a whole picture of current research on PE-related circRNAs, and extend a new perspective for the precise screening and targeted therapy of PE.

CircLZIC regulates ox-LDL-induced HUVEC cell proliferation and apoptosis via Micro-330-5p/NOTCH2 axis in atherosclerosis

Atherosclerosis (AS) is a major chronic non-communicable disease and a primary cause of cardiovascular disease. Recent studies have shown that circRNAs are potential epigenetic factors that regulate vascular endothelial inflammatory responses and AS progression. Therefore, identification of the circRNAs that regulate ox-LDL levels is a critical step to understanding the pathology of AS. Our study is aim to investigate how circLZIC regulates atherosclerosis (AS) via the Micro-330-5p/NOTCH2 regulatory axis. The results showed that CircLZIC and NOTCH2 are highly expressed in human AS clinical samples, while Micro-330-5p is expressed locally. The CCK-8 experiment results showed that circLZIC promotes the proliferation of HUVECS cells. Flow cytometry analysis showed that circLZIC act as an inhibitor of HUVEC cell apoptosis. The expression level of Micro-330-5p can be up-regulated by transfection of small interfering RNA against circLZIC. Further, Starbase predicted that Micro-330-5p could target and regulate NOTCH2. Next, we confirmed that overexpression of Micro-330-5p could significantly reduce the expression of fluorescein using the double Luciferase reporter assay. RIP-qRT-PCR experiment showed that Micro-330-5p and NOTCH2 mRNAs are effectively enriched by ago2 protein. Further, we found that knocking down circLZIC increases the expression of Micro-330-5p and promotes cell apoptosis, while inhibiting the expression of NOTCH2 and cell activity. On the other hand, co-transfection of Micro-330-5p inhibitor decreases Micro-330-5p expression and inhibit cell apoptosis, while increasing NOTCH2 expression and cell activity. In conclusion, CircLZIC regulates HUVEC cell activity by the Micro-330-5p/NOTCH2 signaling pathway, suggesting that circLZIC plays a key role in atherosclerosis development.

Immune-regulatory properties of endovascular extravillous trophoblast cells in human placenta

INTRODUCTION

Uterine spiral artery remodeling is the prerequisite for ensuring adequate blood supply to the maternal-fetal interface during human pregnancy. One crucial cellular event in this process involves the extensive replacement of the spiral artery endothelial cells by endovascular extravillous trophoblasts (enEVTs), a subtype of extravillous trophoblasts (EVTs). However, our understanding of the properties of enEVTs remains limited.

METHODS

Human enEVTs in decidual tissues during early pregnancy was purified using flow sorting by specific makers, NCAM1 and HLA-G. The high-throughput RNA sequencing analysis as well as the cytokine antibody array experiments were carried out to analyze for cell properties. Gene ontology (GO) enrichment, kyoto encyclopedia of genes and genomes (KEGG) enrichment, and gene set enrichment analysis (GSEA) were performed on differentially expressed genes of enEVTs. Immunofluorescent assays were used to verify the analysis results.

RESULTS

Both enEVTs and interstitial EVTs (iEVTs) exhibited gene expression patterns typifying EVT characteristics. Intriguingly, enEVTs displayed gene expression associated with immune responses, particularly reminiscent of M2 macrophage characteristics. The active secretion of multiple cytokines and chemokines by enEVTs provided partial validation for their expression pattern of immune-regulatory genes.

DISCUSSION

Our study reveals the immune-regulatory properties of human enEVTs and provides new insights into their functions and mechanisms involved in spiral artery remodeling.

Icaritin attenuates recurrent spontaneous abortion in mice by modulating Treg/Th17 imbalance via TGF-β/SMAD signaling pathway

Recurrent spontaneous abortion (RSA) is a challenging global issue. Although the cause is unknown, increasing evidence suggests that immunological factors play a crucial role in RSA development. Icaritin (ICT), a natural compound derived from Epimedium, has demonstrated diverse biological activities, including anti-inflammatory, anti-cancer, and immunomodulatory effects. In this study, we aimed to investigate the potential therapeutic role of ICT in mitigating RSA in a mouse model. Specifically, we sought to determine whether ICT could modulate the Treg/Th17 cell imbalance via the TGF-β/SMAD signaling pathway and contributed to improved pregnancy outcomes. We conducted experiments on a mouse model with RSA and administered ICT orally. We then examined the effects of ICT on various types of immune cells including Treg and Th17 cells, and assessed the pregnancy outcomes. We also investigated the potential signaling pathway ICT exerted its effects. Our findings revealed that treatment with ICT led to an increase in Treg cells and a decrease in Th17 cells, which restored immune homeostasis and contributed to improved pregnancy outcomes. Furthermore, our data demonstrated that ICT's effects were mediated through the activation of TGF-β/SMAD signaling components. In conclusion, our study suggested that ICT ameliorated RSA by modulating Treg/Th17 cell imbalance via the TGF-β/SMAD signaling pathway. GENERAL SIGNIFICANCE: Our results highlighted the potential of ICT as a novel therapeutic agent for RSA, offering new insights into the underlying mechanisms and opening avenues for future research and clinical translation.

YAP-mediated trophoblast dysfunction: the common pathway underlying pregnancy complications

Yes-associated protein (YAP) is a pivotal regulator in cellular proliferation, survival, differentiation, and migration, with significant roles in embryonic development, tissue repair, and tumorigenesis. At the maternal-fetal interface, emerging evidence underscores the importance of precisely regulated YAP activity in ensuring successful pregnancy initiation and progression. However, despite the established association between YAP dysregulation and adverse pregnancy outcomes, insights into the impact of aberrant YAP levels in fetal-derived, particularly trophoblast cells, and the ensuing dysfunction at the maternal-fetal interface remain limited. This review comprehensively examines YAP expression and its regulatory mechanisms in trophoblast cells throughout pregnancy. We emphasize its integral role in placental development and maternal-fetal interactions and delve into the correlations between YAP dysregulation and pregnancy complications. A nuanced understanding of YAP's functions during pregnancy could illuminate intricate molecular mechanisms and pave the way for innovative prevention and treatment strategies for pregnancy complications. Video Abstract.

circPTK2 promotes proliferation, migration and invasion of trophoblast cells through the miR-619/WNT7B pathway in preeclampsia

It has been shown that the circular RNA (circRNA) circPTK2 modulates many types of diseases. However, the possible functions as well as the molecular mechanisms of circPTK2 in preeclampsia (PE) and their effects on trophoblast are unknown. Herein, we obtained the placental tissues from 20 pregnant women with PE who delivered in the Yueyang Maternal Child Medicine Health Hospital between 2019 and 2021 to serve as the PE group, and a normal group was composed of 20 healthy pregnant women with normal prenatal examinations. The circPTK2 level was significantly reduced in tissues from the PE group. The expression and localization of circPTK2 were verified using RT-qPCR. CircPTK2 silencing inhibited HTR-8/SVneo growth and migration in vitro. To investigate the underlying mechanism of circPTK2 in PE progression, dual-luciferase reporter assays were conducted. It was found that circPTK2 and WNT7B could bind directly to miR-619, and that circPTK2 affected WNT7B expression by sponging miR-619. To conclude, this study identified the functions and mechanisms of the circPTK2/miR-619/WNT7B axis in PE progression. In this way, circPTK2 has the potential to be used both in diagnostic and therapeutic settings for PE.

Gene-network based analysis of human placental trophoblast subtypes identifies critical genes as potential targets of therapeutic drugs

During early pregnancy, extravillous trophoblasts (EVTs) play a crucial role in modifying the maternal uterine environment. Failures in EVT lineage formation and differentiation can lead to pregnancy complications such as preeclampsia, fetal growth restriction, and pregnancy loss. Despite recent advances, our knowledge on molecular and external factors that control and affect EVT development remains incomplete. Using trophoblast organoid in vitro models, we recently discovered that coordinated manipulation of the transforming growth factor beta (TGFβ) signaling is essential for EVT development. To further investigate gene networks involved in EVT function and development, we performed weighted gene co-expression network analysis (WGCNA) on our RNA-Seq data. We identified 10 modules with a median module membership of over 0.8 and sizes ranging from 1005 (M1) to 72 (M27) network genes associated with TGFβ activation status or in vitro culturing, the latter being indicative for yet undiscovered factors that shape the EVT phenotypes. Lastly, we hypothesized that certain therapeutic drugs might unintentionally interfere with placentation by affecting EVT-specific gene expression. We used the STRING database to map correlations and the Drug-Gene Interaction database to identify drug targets. Our comprehensive dataset of drug-gene interactions provides insights into potential risks associated with certain drugs in early gestation.

NOTCH3 signalling controls human trophoblast stem cell expansion and differentiation

Failures in growth and differentiation of the early human placenta are associated with severe pregnancy disorders such as pre-eclampsia and fetal growth restriction. However, regulatory mechanisms controlling development of placental epithelial cells, the trophoblasts, remain poorly elucidated. Using trophoblast stem cells (TSCs), trophoblast organoids (TB-ORGs) and primary cytotrophoblasts (CTBs) of early pregnancy, we herein show that autocrine NOTCH3 signalling controls human placental expansion and differentiation. The NOTCH3 receptor was specifically expressed in proliferative CTB progenitors and its active form, the nuclear NOTCH3 intracellular domain (NOTCH3-ICD), interacted with the transcriptional co-activator mastermind-like 1 (MAML1). Doxycycline-inducible expression of dominant-negative MAML1 in TSC lines provoked cell fusion and upregulation of genes specific for multinucleated syncytiotrophoblasts, which are the differentiated hormone-producing cells of the placenta. However, progenitor expansion and markers of trophoblast stemness and proliferation were suppressed. Accordingly, inhibition of NOTCH3 signalling diminished growth of TB-ORGs, whereas overexpression of NOTCH3-ICD in primary CTBs and TSCs showed opposite effects. In conclusion, the data suggest that canonical NOTCH3 signalling plays a key role in human placental development by promoting self-renewal of CTB progenitors.

Shared developmental pathways of the placenta and fetal heart

Congenital heart defects (CHD) remain the most common class of birth defect worldwide, affecting 1 in every 110 live births. A host of clinical and morphological indicators of placental dysfunction are observed in pregnancies complicated by fetal CHD and, with the recent emergence of single-cell sequencing capabilities, the molecular and physiological associations between the embryonic heart and developing placenta are increasingly evident. In CHD pregnancies, a hostile intrauterine environment may negatively influence and alter fetal development. Placental maldevelopment and dysfunction creates this hostile in-utero environment and may manifest in the development of various subtypes of CHD, with downstream perfusion and flow-related alterations leading to yet further disruption in placental structure and function. The adverse in-utero environment of CHD-complicated pregnancies is well studied, however the specific etiological role that the placenta plays in CHD development remains unclear. Many mouse and rat models have been used to characterize the relationship between CHD and placental dysfunction, but these paradigms present substantial limitations in the assessment of both the heart and placenta. Improvements in non-invasive placental assessment can mitigate these limitations and drive human-specific investigation in relation to fetal and placental development. Here, we review the clinical, structural, and molecular relationships between CHD and placental dysfunction, the CHD subtype-dependence of these changes, and the future of Placenta-Heart axis modeling and investigation.

TimeTalk uses single-cell RNA-seq datasets to decipher cell-cell communication during early embryo development

Early embryonic development is a dynamic process that relies on proper cell-cell communication to form a correctly patterned embryo. Early embryo development-related ligand-receptor pairs (eLRs) have been shown to guide cell fate decisions and morphogenesis. However, the scope of eLRs and their influence on early embryo development remain elusive. Here, we developed a computational framework named TimeTalk from integrated public time-course mouse scRNA-seq datasets to decipher the secret of eLRs. Extensive validations and analyses were performed to ensure the involvement of identified eLRs in early embryo development. Process analysis identified that eLRs could be divided into six temporal windows corresponding to sequential events in the early embryo development process. With the interpolation strategy, TimeTalk is powerful in revealing paracrine settings and studying cell-cell communication during early embryo development. Furthermore, by using TimeTalk in the blastocyst and blastoid models, we found that the blastoid models share the core communication pathways with the epiblast and primitive endoderm lineages in the blastocysts. This result suggests that TimeTalk has transferability to other bio-dynamic processes. We also curated eLRs recognized by TimeTalk, which may provide valuable clues for understanding early embryo development and relevant disorders.

Extensive rewiring of the gene regulatory interactions between in vitro-produced conceptuses and endometrium during attachment

Pregnancy loss is a significant problem when embryos produced in vitro are transferred to a synchronized uterus. Currently, mechanisms that underlie losses of in vitro-produced embryos during implantation are largely unknown. We investigated this problem using cattle as a model of conceptus attachment by analyzing transcriptome data of paired extraembryonic membrane and endometrial samples collected on gestation days 18 and 25, which spans the attachment window in cattle. We identified that the transfer of an in vitro-produced embryo caused a significant alteration in transcript abundance of hundreds of genes in extraembryonic and endometrial tissues on gestation days 18 and 25, when compared to pregnancies initiated by artificial insemination. Many of the genes with altered transcript abundance are associated with biological processes that are relevant to the establishment of pregnancy. An integrative analysis of transcriptome data from the conceptus and endometrium identified hundreds of putative ligand-receptor pairs. There was a limited variation of ligand-receptor pairs in pregnancies initiated by in vitro-produced embryos on gestation day 18, and no alteration was observed on gestation day 25. In parallel, we identified that in vitro production of embryos caused an extensive alteration in the coexpression of genes expressed in the extraembryonic membranes and the corresponding endometrium on both gestation days. Both the transcriptional dysregulation that exists in the conceptus or endometrium independently and the rewiring of gene transcription between the conceptus and endometrium are a potential component of the mechanisms that contribute to pregnancy losses caused by in vitro production of embryos.

Mucin1 induced trophoblast dysfunction in gestational diabetes mellitus via Wnt/β-catenin pathway

BACKGROUND

To elucidate the role of Mucin1 (MUC1) in the trophoblast function (glucose uptake and apoptosis) of gestational diabetes mellitus (GDM) women through the Wnt/β-catenin pathway.

METHODS

Glucose uptake was analyzed by plasma GLUT1 and GLUT4 levels with ELISA and measured by the expression of GLUT4 and INSR with immunofluorescence and Western blotting. Apoptosis was measured by the expression of Bcl-2 and Caspase3 by Western blotting and flow cytometry. Wnt/β-catenin signaling measured by Western blotting. In vitro studies were performed using HTR-8/SVneo cells that were cultured and treated with high glucose (HG), sh-MUC1 and FH535 (inhibitor of Wnt/β-catenin signaling).

RESULTS

MUC1 was highly expressed in the placental trophoblasts of GDM, and the Wnt/β-catenin pathway was activated, along with dysfunction of glucose uptake and apoptosis. MUC1 knockdown resulted in increased invasiveness and decreased apoptosis in trophoblast cells. The initial linkage between MUC1, the Wnt/β-catenin pathway, and glucose uptake was confirmed by using an HG-exposed HTR-8/SVneo cell model with MUC1 knockdown. MUC1 knockdown inhibited the Wnt/β-catenin signaling pathway and reversed glucose uptake dysfunction and apoptosis in HG-induced HTR-8/SVneo cells. Meanwhile, inhibition of Wnt/β-catenin signaling could also reverse the dysfunction of glucose uptake and apoptosis.

CONCLUSIONS

In summary, the increased level of MUC1 in GDM could abnormally activate the Wnt/β-catenin signaling pathway, leading to trophoblast dysfunction, which may impair glucose uptake and induce apoptosis in placental tissues of GDM women.

Charting the Path: Navigating Embryonic Development to Potentially Safeguard against Congenital Heart Defects

Congenital heart diseases (CHDs) are structural or functional defects present at birth due to improper heart development. Current therapeutic approaches to treating severe CHDs are primarily palliative surgical interventions during the peri- or prenatal stages, when the heart has fully developed from faulty embryogenesis. However, earlier interventions during embryonic development have the potential for better outcomes, as demonstrated by fetal cardiac interventions performed in utero, which have shown improved neonatal and prenatal survival rates, as well as reduced lifelong morbidity. Extensive research on heart development has identified key steps, cellular players, and the intricate network of signaling pathways and transcription factors governing cardiogenesis. Additionally, some reports have indicated that certain adverse genetic and environmental conditions leading to heart malformations and embryonic death may be amendable through the activation of alternative mechanisms. This review first highlights key molecular and cellular processes involved in heart development. Subsequently, it explores the potential for future therapeutic strategies, targeting early embryonic stages, to prevent CHDs, through the delivery of biomolecules or exosomes to compensate for faulty cardiogenic mechanisms. Implementing such non-surgical interventions during early gestation may offer a prophylactic approach toward reducing the occurrence and severity of CHDs.

Trophoblast Differentiation: Mechanisms and Implications for Pregnancy Complications

Placental development is a tightly controlled event, in which cell expansion from the trophectoderm occurs in a spatiotemporal manner. Proper trophoblast differentiation is crucial to the vitality of this gestational organ. Obstructions to its development can lead to pregnancy complications, such as preeclampsia, fetal growth restriction, and preterm birth, posing severe health risks to both the mother and offspring. Currently, the only known treatment strategy for these complications is delivery, making it an important area of research. The aim of this review was to summarize the known information on the development and mechanistic regulation of trophoblast differentiation and highlight the similarities in these processes between the human and mouse placenta. Additionally, the known biomarkers for each cell type were compiled to aid in the analysis of sequencing technologies.