Establishment of the fetal-maternal interface: developmental events in human implantation and placentation

Immunotoxicological disruption of pregnancy as a new research area in immunotoxicology

Immune mechanisms associated with normal pregnancy have only been being substantively investigated since the early 1990s. In parallel with the progress in that area of research, in the past few years it has become increasingly clear that several xenobiotics - including a variety of environmental chemicals, pharmaceuticals, and metals are considered to be both generally immunotoxic and specifically able to affect pregnancy. Among these, there is intense interest regarding potential effects from synthetic cannabinoids, immune checkpoint inhibitors, nanometals, and microplastics, with immunotoxic events that impact on pregnancy being shown for these agents. For instance, phytocannabinoids have been shown to interfere with reproduction in mice through effects on the endocannabinoid system. Because of effects of immune enhancement, as a requirement for regulatory submission, co-inhibitory immune checkpoint molecule inhibitors were also evaluated for effects on pregnancy. Similarly, because of increasing use and concerns about incidental environmental exposures, nanometals, and micro-plastics have also been examined for effects. Several studies in humans or mice showed that exposures to each during gestation increased the risk/rate of fetal loss, in part, by disruption of the placenta-associated immune system. Furthermore, signaling by endogenous danger molecules and/or impairment of physiological intercellular mediators may have contributed to the pregnancy loss. As there are clearly a variety of immunotoxic effects that can impact on a pregnancy, this review attempts to briefly introduce immune mechanisms associated with pregnancy as well as reasons for its loss, and proposes that 'immunotoxicological disruption of pregnancy' be accepted as a new research area in immunotoxicology.

Unveiling Gestational Diabetes: An Overview of Pathophysiology and Management

Gestational diabetes mellitus (GDM) is characterized by an inadequate pancreatic β-cell response to pregnancy-induced insulin resistance, resulting in hyperglycemia. The pathophysiology involves reduced incretin hormone secretion and signaling, specifically decreased glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), impairing insulinotropic effects. Pro-inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6), impair insulin receptor substrate-1 (IRS-1) phosphorylation, disrupting insulin-mediated glucose uptake. β-cell dysfunction in GDM is associated with decreased pancreatic duodenal homeobox 1 (PDX1) expression, increased endoplasmic reticulum stress markers (CHOP, GRP78), and mitochondrial dysfunction leading to impaired ATP production and reduced glucose-stimulated insulin secretion. Excessive gestational weight gain exacerbates insulin resistance through hyperleptinemia, which downregulates insulin receptor expression via JAK/STAT signaling. Additionally, hypoadiponectinemia decreases AMP-activated protein kinase (AMPK) activation in skeletal muscle, impairing GLUT4 translocation. Placental hormones such as human placental lactogen (hPL) induce lipolysis, increasing circulating free fatty acids which activate protein kinase C, inhibiting insulin signaling. Placental 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) overactivity elevates cortisol levels, which activate glucocorticoid receptors to further reduce insulin sensitivity. GDM diagnostic thresholds (≥92 mg/dL fasting, ≥153 mg/dL post-load) are lower than type 2 diabetes to prevent fetal hyperinsulinemia and macrosomia. Management strategies focus on lifestyle modifications, including dietary carbohydrate restriction and exercise. Pharmacological interventions, such as insulin or metformin, aim to restore AMPK signaling and reduce hepatic glucose output. Emerging therapies, such as glucagon-like peptide-1 receptor (GLP-1R) agonists, show potential in improving glycemic control and reducing inflammation. A mechanistic understanding of GDM pathophysiology is essential for developing targeted therapeutic strategies to prevent both adverse pregnancy outcomes and the progression to overt diabetes in affected women.

Environmental pollutant SO₂ exposure affects trophoblast function involving an ER stress pathway

Sulphur dioxide (SO₂) is a toxic air pollutant with deleterious effects on the respiratory, cardiovascular, endocrine and reproductive systems. SO₂, being freely diffusible, can cross the placenta and reach the fetal system. Previous studies have reported the association between SO₂ exposure and adverse pregnancy and fetal outcomes without much emphasis on its molecular aspects. The present study has investigated the adverse consequences of SO₂ derivatives on the two key trophoblast functions critical for placentation: invasion and fusion. SO₂ exposure inhibited the fusogenic potential of BeWo cells, as well as the invasion and migratory ability of the extravillous HTR8/SVneo cells. A molecular insight revealed dysregulated endoplasmic reticulum stress, with an altered epigenetic state as seen by histone modifications following SO₂ exposure. Collectively, our findings revealed the harmful effect of SO₂ and its consequences on the placental function. We therefore elucidated the detrimental impact of SO₂ exposure on trophoblast cells and the possible health consequences that may contribute to pregnancy-related complications as a result of compromised placental function. KEY POINTS: Sulphur dioxide (SO₂) derivatives severely impaired trophoblasts migration, invasion and its ability of fusogenic differentiation. SO₂ derivatives appear to affect trophoblast cell interactions, thereby affecting its 3D organization and its capacity to form spheroids. Mechanistic insight into these events indicates SO₂ derivatives mediated the induction of endoplasmic reticulum stress and inflammation, as well as altered histone-3 markers. We therefore conclude that SO₂ exposure has a detrimental effect on placental trophoblast cells. Long-term exposure during pregnancy may result in an adverse outcome.

The role of vitamin D deficiency in placental dysfunction: A systematic review

Introduction

Vitamin D plays a critical role in pregnancy, supporting placental function via angiogenesis, immune regulation, and nutrient transport. Deficiency in vitamin D during gestation is associated with complications such as preeclampsia, intrauterine growth restriction (IUGR), and preterm birth. However, the mechanisms linking vitamin D deficiency to placental dysfunction remain inadequately understood, highlighting the need for systematic evaluation.

Methods

A systematic review was conducted in adherence to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, with searches in PubMed, Scopus, and Web of Science for studies published within the last 20 years. Inclusion criteria targeted human studies examining the association between vitamin D and placental function, including randomized controlled trials, cohort studies, and case-control studies. A total of 10 studies were included following rigorous screening and quality assessment.

Results

Findings from human studies indicate that maternal vitamin D deficiency significantly impairs placental function by reducing vascular integrity, downregulating nutrient transporters, and promoting inflammation. Mechanistic evidence highlights decreased expression of vascular endothelial growth factor (VEGF) and increased inflammatory cytokines in vitamin D-deficient pregnancies. Supplementation with active vitamin D [1α,25(OH)2D3] mitigated these adverse effects, restoring placental growth, improving nutrient transport, and reducing inflammation. Notably, population-specific differences and sex-specific responses to vitamin D sufficiency were observed.

Conclusions

Vitamin D is essential for optimal placental function and pregnancy outcomes. This review underscores the need for standardized supplementation protocols and further research into long-term and population-specific effects of vitamin D. Addressing these gaps can inform targeted interventions to reduce pregnancy complications and improve maternal-fetal health.

Cytokine modulation and immunoregulation of uterine NK cells in pregnancy disorders

Uterine natural killer (uNK) cells play a pivotal role in promoting placental development and supporting maternal-fetal immune tolerance, primarily through cytokine regulation and growth factor production. While the importance of uNK cells in pregnancy is well-established, the mechanisms of their interactions with trophoblasts and contributions to various pregnancy complications remain incompletely understood. This review highlights recent advancements in understanding uNK cell functions, with a focus on cytokine production, growth factor secretion, and receptor-ligand interactions, particularly involving killer immunoglobulin-like receptors (KIR) and human leukocyte antigen-C (HLA-C). We explore how uNK cell dysfunction contributes to pregnancy complications, including preeclampsia, recurrent pregnancy loss, and placenta accreta spectrum (PAS) disorders, emphasizing their roles in immune tolerance and placental health. By detailing the distinct cytokine signaling pathways and functional subtypes of uNK cells, this review provides insights into their regulatory mechanisms essential for pregnancy maintenance. Additionally, we discuss emerging therapeutic strategies targeting uNK-trophoblast interactions and propose future research directions, including the development of non-invasive biomarkers and personalized interventions. This comprehensive review addresses critical knowledge gaps, aiming to advance research in reproductive immunology and guide therapeutic innovations in maternal health.

The Molecular Biology of Placental Transport of Calcium to the Human Foetus

From fertilisation to delivery, calcium must be transported into and within the foetoplacental unit for intracellular signalling. This requires very rapid, precisely located Ca2+ transfers. In addition, from around the eighth week of gestation, increasing amounts of calcium must be routed directly from maternal blood to the foetus for bone mineralisation through a flow-through system, which does not impact the intracellular Ca2+ concentration. These different processes are mediated by numerous membrane-sited Ca2+ channels, transporters, and exchangers. Understanding the mechanisms is essential to direct interventions to optimise foetal development and postnatal bone health and to protect the mother and foetus from pre-eclampsia. Ethical issues limit the availability of human foetal tissue for study. Our insight into the processes of placental Ca2+ handling is advancing rapidly, enabled by developing genetic, analytical, and computer technology. Because of their diverse sources, the reports of new findings are scattered. This review aims to pull the data together and to highlight areas of uncertainty. Areas needing clarification include trafficking, membrane expression, and recycling of channels and transporters in the placental microvilli; placental metabolism of vitamin D in gestational diabetes and pre-eclampsia; and the vascular effects of increased endothelial Orai expression by pregnancy-specific beta-1-glycoproteins PSG1 and PSG9.

Preimplantation trophectoderm: A 'quick-fix' protector for embryo survival?

The trophectoderm (TE) epithelium forms the outer layer of the mammalian blastocyst and generates the blastocoel through vectorial transport. Its differentiation during cleavage, studied mainly in mouse, is integrated with blastocyst morphogenesis with key roles for cell polarisation, asymmetric cell divisions, cell signalling, regulatory transcription factors and cellular inheritance. The TE provides a physical and cellular protection to the emerging lineages of the embryo essential for the integrity of blastocyst development. Here, two examples of TE differentiation are considered in some detail where this immediate protective function for embryo survival is assessed: (i) cellular processes from TE at the polar-mural junctional zone in the early blastocyst that later form filopodia traversing the blastocoel, and (ii) the endocytic system which matures and polarises during differentiation. Understanding the broad role for TE in regulating early morphogenesis and environmental protection of the embryo, including these two examples, have clinical as well as biological relevance.

SARS-CoV-2 Activated Peripheral Blood Mononuclear Cells (PBMCs) Do Not Provoke Adverse Effects in Trophoblast Spheroids

PROBLEM

Although it is still uncertain whether Severe Acute Respiratory Coronavirus (SARS-CoV-2) placental infection and vertical transmission occur, inflammation during early pregnancy can have devastating consequences for gestation itself and the growing fetus. If and how SARS-CoV-2-specific immune cells negatively affect placenta functionality is still unknown.

METHOD OF STUDY

We stimulated peripheral blood mononuclear cells (PBMCs) from women of reproductive age with SARS-CoV-2 peptides and cocultured them with trophoblast spheroids (HTR-8/SVneo and JEG-3) to dissect if SARS-CoV-2-activated immune cells can interfere with trophoblast functionality. The activation and cytokine profile of the PBMCs were determined using multicolor flow cytometry. The functionality of trophoblast spheroids was assessed using microscopy, enzyme-linked immunosorbent assay (ELISA), and RT-qPCR.

RESULTS

SARS-CoV-2 S and M peptides significantly activated PBMCs (monocytes, NK cells, and T cells with memory subsets) and induced the upregulation of proinflammatory cytokines, such as IFNγ. The activated PBMCs did not impact the viability, growth rate, and invasion capabilities of trophoblast spheroids. Furthermore, the hormonal production of hCG by JEG-3 spheroids was not compromised upon coculture with the activated PBMCs. mRNA transcript levels of genes involved in trophoblast spheroid functional pathways were also not dysregulated after coculture.

CONCLUSIONS

Together, the findings of our in vitro coculture model, although not fully representative of in vivo conditions, strongly support the claim that the interaction of SARS-CoV-2-activated peripheral blood immune cells with trophoblast cells at the fetal-maternal interface does not negatively affect trophoblast functionality. This goes in hand with the recommendation of vaccinating pregnant women in their first trimester.

Epigenetic Biomarkers in Thrombophilia-Related Pregnancy Complications: Mechanisms, Diagnostic Potential, and Therapeutic Implications: A Narrative Review

Pregnancy complications associated with thrombophilia represent significant risks for maternal and fetal health, leading to adverse outcomes such as pre-eclampsia, recurrent pregnancy loss, and intra-uterine growth restriction (IUGR). They are caused by disruptions in key physiological processes, including the coagulation cascade, trophoblast invasion, angiogenesis, and immune control. Recent advancements in epigenetics have revealed that non-coding RNAs, especially microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and extracellular vesicles (EVs) carrying these RNAs, play crucial roles in the regulation of these biological processes. This review aims to identify the epigenetic biomarkers that are the best candidates for evaluating thrombophilia-related pregnancy complications and for assessing the efficacy of anticoagulant and antiaggregant therapies. We emphasize their potential integration into personalized treatment plans, aiming to improve the risk assessment and therapy strategies for thrombophilic pregnancies. Future research should focus on validating these epigenetic biomarkers and establishing standardized protocols to enable their integration into clinical practice, paving the way for a precision medicine approach in obstetric care.

Dendritic cells under the control of the preimplantation embryo secretome: an in vitro study

OBJECTIVE

To study the crosstalk between maternal immune cells and the developing embryo by investigating the immunogenic properties of human blastocyst spent media (SM) on dendritic cells.

METHODS

In this prospective multicenter experimental study, human preimplantation embryo spent media were collected after blastocyst formation, grouped based on successful or unsuccessful implantation, and analyzed by protein array or used to stimulate monocyte derived dendritic cells (moDC). The immunomodulatory properties of SM on moDC were investigated by analyzing changes in phenotype, cytokine secretion, indoleamine 2,3-dioxygenase (IDO) activity, and ability to activate T cells.

RESULTS

A plethora of cytokines and growth factors secreted from preimplantation embryos was detected. Exposure to embryo SM altered the phenotype of moDC in a manner dependent on the implantation outcome. Specifically, SM from non-implanted embryos increased the expression of co-stimulatory molecules and activation markers on moDC. Furthermore, SM treated dendritic cells secreted low levels of cytokines and growth factors and were able to stimulate naïve T cells. Activation of IDO was decreased in moDC after stimulation with SM.

CONCLUSIONS

Our findings show that human preimplantation embryos secrete an abundance of molecules with the ability to significantly affect and even regulate immune cells in their environment.

Gestational Interrelationships among Gut-Metabolism-Transcriptome in Regulating Early Embryo Implantation and Placental Development in Mice

Decidualization of the uterine endometrium is a critical process for embryo implantation in mammals, primarily occurring on gestational day 8 in pregnant mice. However, the interplay between the maternal gut microbiome, metabolism, and the uterus at this specific time point remains poorly understood. This study employed a multi-omics approach to investigate the metabolic, gut microbiome, and transcriptomic changes associated with early pregnancy (gestational day 8 (E8)) in mice. Serum metabolomics revealed a distinct metabolic profile at E8 compared to controls, with the differential metabolites primarily enriched in amino acid metabolism pathways. The gut microbial composition showed that E8 mice exhibited higher alpha-diversity and a significant shift in beta-diversity. Specifically, the E8 group displayed a decrease in pathogenic Proteobacteria and an increase in beneficial Bacteroidetes and S24-7 taxa. Transcriptomics identified myriads of distinct genes between the E8 and control mice. The differentially expressed genes were enriched in pathways involved in alanine, aspartate, and glutamate metabolism, PI3K-Akt signaling, and the PPAR signaling pathway. Integrative analysis of the multi-omics data uncovered potential mechanistic relationships among the differential metabolites, gut microbiota, and uterine gene expression changes. Notably, the gene Asns showed strong correlations with specific gut S24-7 and metabolite L-Aspartatic acid, suggesting its potential role in mediating the crosstalk between the maternal environment and embryo development during early pregnancy. These findings provide valuable insights into the complex interplay between the maternal metabolome, the gut microbiome, and the uterine transcriptome in the context of early pregnancy, which may contribute to our understanding of the underlying mechanisms of embryo implantation and development.

The Enigmatic Interplay of Interleukin-10 in the Synergy of HIV Infection Comorbid with Preeclampsia

Cytokines coordinate the intricate choreography of the immune system, directing cellular activities that mediate inflammation, pathogen defense, pathology and tissue repair. Within this spectrum, the anti-inflammatory prowess of interleukin-10 (IL-10) predominates in immune homeostasis. In normal pregnancy, the dynamic shift of IL-10 across trimesters maintains maternal immune tolerance ensuring fetal development and pregnancy success. Unravelling the dysregulation of IL-10 in pregnancy complications is vital, particularly in the heightened inflammatory condition of preeclampsia. Of note, a reduction in IL-10 levels contributes to endothelial dysfunction. In human immunodeficiency virus (HIV) infection, a complex interplay of IL-10 occurs, displaying a paradoxical paradigm of being immune-protective yet aiding viral persistence. Genetic variations in the IL-10 gene further modulate susceptibility to HIV infection and preeclampsia, albeit with nuanced effects across populations. This review outlines the conceptual framework underlying the role of IL-10 in the duality of normal pregnancy and preeclampsia together with HIV infection, thus highlighting its regulatory mechanisms and genetic influences. Synthesizing these findings in immune modulation presents avenues for therapeutic interventions in pregnancy complications comorbid with HIV infection.

Placental growth factor mediates pathological uterine angiogenesis by activating the NFAT5-SGK1 signaling axis in the endometrium: implications for preeclampsia development

After menstruation the uterine spiral arteries are repaired through angiogenesis. This process is tightly regulated by the paracrine communication between endometrial stromal cells (EnSCs) and endothelial cells. Any molecular aberration in these processes can lead to complications in pregnancy including miscarriage or preeclampsia (PE). Placental growth factor (PlGF) is a known contributing factor for pathological angiogenesis but the mechanisms remain poorly understood. In this study, we investigated whether PlGF contributes to pathological uterine angiogenesis by disrupting EnSCs and endothelial paracrine communication. We observed that PlGF mediates a tonicity-independent activation of nuclear factor of activated T cells 5 (NFAT5) in EnSCs. NFAT5 activated downstream targets including SGK1, HIF-1α and VEGF-A. In depth characterization of PlGF - conditioned medium (CM) from EnSCs using mass spectrometry and ELISA methods revealed low VEGF-A and an abundance of extracellular matrix organization associated proteins. Secreted factors in PlGF-CM impeded normal angiogenic cues in endothelial cells (HUVECs) by downregulating Notch-VEGF signaling. Interestingly, PlGF-CM failed to support human placental (BeWo) cell invasion through HUVEC monolayer. Inhibition of SGK1 in EnSCs improved angiogenic effects in HUVECs and promoted BeWo invasion, revealing SGK1 as a key intermediate player modulating PlGF mediated anti-angiogenic signaling. Taken together, perturbed PlGF-NFAT5-SGK1 signaling in the endometrium can contribute to pathological uterine angiogenesis by negatively regulating EnSCs-endothelial crosstalk resulting in poor quality vessels in the uterine microenvironment. Taken together the signaling may impact on normal trophoblast invasion and thus placentation and, may be associated with an increased risk of complications such as PE.

Single-cell transcriptomics reveal differences between chorionic and basal plate cytotrophoblasts and trophoblast stem cells

Cytotrophoblast (CTB) of the early gestation human placenta are bipotent progenitor epithelial cells, which can differentiate into invasive extravillous trophoblast (EVT) and multinucleated syncytiotrophoblast (STB). Trophoblast stem cells (TSC), derived from early first trimester placentae, have also been shown to be bipotential. In this study, we set out to probe the transcriptional diversity of first trimester CTB and compare TSC to various subgroups of CTB. We performed single-cell RNA sequencing on six normal placentae, four from early (6-8 weeks) and two from late (12-14 weeks) first trimester, of which two of the early first trimester cases were separated into basal (maternal) and chorionic (fetal) fractions prior to sequencing. We also sequenced three TSC lines, derived from 6-8 week placentae, to evaluate similarities and differences between primary CTB and TSC. CTB clusters displayed notable distinctions based on gestational age, with early first trimester placentae showing enrichment for specific CTB subtypes, further influenced by origin from the basal or chorionic plate. Differential expression analysis of CTB from basal versus chorionic plate highlighted pathways associated with proliferation, unfolded protein response, and oxidative phosphorylation. We identified trophoblast states representing initial progenitor CTB, precursor STB, precursor and mature EVT, and multiple CTB subtypes. CTB progenitors were enriched in early first trimester placentae, with basal plate cells biased toward EVT, and chorionic plate cells toward STB, precursors. Clustering and trajectory inference analysis indicated that TSC were most like EVT precursor cells, with only a small percentage of TSC on the pre-STB differentiation trajectory. This was confirmed by flow cytometric analysis of 6 different TSC lines, which showed uniform expression of proximal column markers ITGA2 and ITGA5. Additionally, we found that ITGA5+ CTB could be plated in 2D, forming only EVT upon spontaneous differentiation, but failed to form self-renewing organoids; conversely, ITGA5-CTB could not be plated in 2D, but readily formed organoids. Our findings suggest that distinct CTB states exist in different regions of the placenta as early as six weeks gestation and that current TSC lines most closely resemble ITGA5+ CTB, biased toward the EVT lineage.

Effect of blastocyst development on hatching and embryo implantation

The mammalian zygote, formed after a sperm fertilizes an egg, undergoes several rounds of mitosis and morphogenesis to form the blastocyst. During the peri-implantation period, the blastocyst hatches out of the zona pellucida (ZP) and invades the receptive uterine endometrium. This process promotes maternal-fetal dialogue at the physiological and molecular level, thereby initiating the implantation process. Blastocyst hatching is a consequence of elevated osmotic pressure due to active Na+/K+ ion transporter in the blastocyst cavity, as well as proteases produced by trophectoderm (TE) that hydrolyze the ZP. This review summarizes the process underpinning blastocyst hatching, such as the hatching schedule, the location of TEs during initial hatching out of the ZP, the molecules involved in blastocyst hatching, and how these processes affect implantation events. Additionally, we focus on identifying crucial molecules that may influence the quality of implantation and predict the outcome of embryo implantation. Further understanding the mechanism of these molecules may help us to improve the efficiency of Assisted reproductive technology (ART) in livestock breeding. This review provides insight into embryonic development, specifically during the short-term process of blastocyst hatching and its effects on the following implantation.

Unraveling the Multifaceted Roles of Extracellular Vesicles: Insights into Biology, Pharmacology, and Pharmaceutical Applications for Drug Delivery

Extracellular vesicles (EVs) are nanoparticles released from various cell types that have emerged as powerful new therapeutic option for a variety of diseases. EVs are involved in the transmission of biological signals between cells and in the regulation of a variety of biological processes, highlighting them as potential novel targets/platforms for therapeutics intervention and/or delivery. Therefore, it is necessary to investigate new aspects of EVs' biogenesis, biodistribution, metabolism, and excretion as well as safety/compatibility of both unmodified and engineered EVs upon administration in different pharmaceutical dosage forms and delivery systems. In this review, we summarize the current knowledge of essential physiological and pathological roles of EVs in different organs and organ systems. We provide an overview regarding application of EVs as therapeutic targets, therapeutics, and drug delivery platforms. We also explore various approaches implemented over the years to improve the dosage of specific EV products for different administration routes.

Oleuropein Stimulates Migration of Human Trophoblast Cells and Expression of Invasion-Associated Markers

Successful pregnancy establishment requires highly synchronized cross talk between the invasive trophoblast cells and the receptive maternal endometrium. Any disturbances in this tightly regulated process may lead to pregnancy complications. Local factors such as nutrients, hormones, cytokines and reactive oxygen species modulate the invasion of extravillous trophoblasts through critical signaling cascades. Epidemiological studies strongly indicate that a Mediterranean diet can significantly impact molecular pathways during placentation. Therefore, the aim of the current study was to examine whether oleuropein (OLE), one of the main compounds of the Mediterranean diet, may influence trophoblast cell adhesion and migration, as well as the expression of invasion-associated molecular markers and inflammatory pathways fostering these processes. HTR-8/SVneo cells were incubated with OLE at selected concentrations of 10 and 100 µM for 24 h. Results showed that OLE did not affect trophoblast cell viability, proliferation and adhesion after 24 h in in vitro treatment. The mRNA expression of integrin subunits α1, α5 and β1, as well as matrix-degrading enzymes MMP-2 and -9, was significantly increased after treatment with 10 µM OLE. Furthermore, OLE at a concentration of 10 µM significantly increased the protein expression of integrin subunits α1 and β1. Also, OLE inhibited the activation of JNK and reduced the protein expression of COX-2. Finally, a lower concentration of OLE 10 µM significantly stimulated migration of HTR-8/SVneo cells. In conclusion, the obtained results demonstrate the effects of OLE on the function of trophoblast cells by promoting cell migration and stimulating the expression of invasion markers. As suggested from results, these effects may be mediated via inhibition of the JNK signaling pathway.

HMGB1: a double-edged sword and therapeutic target in the female reproductive system

HMGB1 that belongs to the High Mobility Group-box superfamily, is a nonhistone chromatin associated transcription factor. It is present in the nucleus of eukaryotes and can be actively secreted or passively released by kinds of cells. HMGB1 is important for maintaining DNA structure by binding to DNA and histones, protecting it from damage. It also regulates the interaction between histones and DNA, affecting chromatin packaging, and can influence gene expression by promoting nucleosome sliding. And as a DAMP, HMGB1 binding to RAGE and TLRs activates NF-κB, which triggers the expression of downstream genes like IL-18, IL-1β, and TNF-α. HMGB1 is known to be involved in numerous physiological and pathological processes. Recent studies have demonstrated the significance of HMGB1 as DAMPs in the female reproductive system. These findings have shed light on the potential role of HMGB1 in the pathogenesis of diseases in female reproductive system and the possibilities of HMGB1-targeted therapies for treating them. Such therapies can help reduce inflammation and metabolic dysfunction and alleviate the symptoms of reproductive system diseases. Overall, the identification of HMGB1 as a key player in disease of the female reproductive system represents a significant breakthrough in our understanding of these conditions and presents exciting opportunities for the development of novel therapies.

Pathophysiological Insight into Fatty Acid-Binding Protein-4: Multifaced Roles in Reproduction, Pregnancy, and Offspring Health

Fatty acid-binding protein-4 (FABP4), commonly known as adipocyte-fatty acid-binding protein (A-FABP), is a pleiotropic adipokine that broadly affects immunity and metabolism. It has been increasingly recognized that FABP4 dysfunction is associated with various metabolic syndromes, including obesity, diabetes, cardiovascular diseases, and metabolic inflammation. However, its explicit roles within the context of women's reproduction and pregnancy remain to be investigated. In this review, we collate recent studies probing the influence of FABP4 on female reproduction, pregnancy, and even fetal health. Elevated circulating FABP4 levels have been found to correlate with impaired reproductive function in women, such as polycystic ovary syndrome and endometriosis. Throughout pregnancy, FABP4 affects maternal-fetal interface homeostasis by affecting both glycolipid metabolism and immune tolerance, leading to adverse pregnancy outcomes, including miscarriage, gestational obesity, gestational diabetes, and preeclampsia. Moreover, maternal FABP4 levels exhibit a substantial linkage with the metabolic health of offspring. Herein, we discuss the emerging significance and potential application of FABP4 in reproduction and pregnancy health and delve into its underlying mechanism at molecular levels.