Extracellular vesicles derived from M1 macrophages deliver miR-146a-5p and miR-146b-5p to suppress trophoblast migration and invasion by targeting TRAF6 in recurrent spontaneous abortion

Hypermethylation and low expression of FOXM1 predisposes women to unexplained recurrent miscarriage by impairing trophoblast stem cell proliferation

Recurrent miscarriage (RM) is a distressing pregnancy complication with an unknown etiology. Increasing evidence indicates the relevance of dysregulation of human trophoblast stem cells (hTSCs), which may play a role in the development of RM. However, the potential molecular regulatory mechanism underlying the initiation and maintenance of hTSCs is yet to be fully elucidated. In this study, we performed data analysis and identified Forkhead box M1 (FOXM1) as a potential factor associated with RM. FOXM1 is a typical transcription factor known for its involvement in various pathophysiological processes, while the precise function of FOXM1 functions in hTSCs and RM remains incompletely understood. Utilizing RNA-seq, CUT&Tag, ChIP-qPCR, and sodium bisulfite conversion methods for methylation analysis, we elucidate the underlying regulatory mechanisms of FOXM1 in hTSCs and its implications in RM. Our findings demonstrate the relative high expression of FOXM1 in proliferating cytotrophoblasts (CTBs) compared to differentiated extravillous cytotrophoblasts (EVTs) and syncytiotrophoblasts (STBs). Besides, we provide evidence supporting a significant correlation between FOXM1 downregulation and the incidence of RM. Furthermore, we demonstrate the significant role of FOXM1 in regulating hTSCs proliferation and cell cycle through the transcriptional regulation of CDKN3, CCNB2, CCNA2, MAD2L1 and CDC25C. Notably, we observed a correlation between the downregulation of FOXM1 in RM and hypermethylation in its promoter region. Collectively, these results provide insights into the impact of FOXM1 on trophoblast regulation and offer a novel perspective on RM.

Dysregulated lncSNHG12 suppresses the invasion and migration of trophoblasts by regulating Dio2/Snail axis to involve in recurrent spontaneous abortion

Recurrent spontaneous abortion (RSA) is a complex pathological process involving diverse factors, in which the dysregulated functions of trophoblasts cannot be ignored. Long noncoding RNA (lncRNA) has been reported to play a significant role in regulating the functions of trophoblasts in RSA. However, the impact and potential mechanism of lncRNA small nucleolar RNA host gene 12 (lncSNHG12) remain unclear. The role of lncSNHG12 in RSA was investigated through in vivo experiments and clinical samples. Co-IP and RNA pull down were conducted to explore the molecular mechanisms in trophoblasts. Our results showed that lncSNHG12 promoted the migration and invasion of trophoblasts by interacting with Iodothyronine deiodinase 2 (Dio2), which regulating the EMT process of trophoblasts by interacting with Snail. Moreover, in vivo experiments confirmed that lncSNHG12 could improve the fetal absorption rate of the abortion mice. The clinical samples revealed that lncSNHG12, Dio2 and Snail were down-regulated in the villous tissues of RSA patients, and positive correlations were confirmed between lncSNHG12 and Dio2, as well as Dio2 and Snail. In summary, the lncSNHG12/Dio2/Snail axis might be involved in the development of RSA by regulating the invasion and migration of trophoblasts. Abbreviations: RSA, recurrent spontaneous abortion; EVTs, extravillous trophoblasts; EMT, epithelial-to-mesenchymal transition; lncRNA, long non-coding RNA; Dio2, iodothyronine deiodinase 2; SNHGs, small nuclear RNA host genes; snoRNAs, small nuclear cell RNAs; LPS, lipopolysaccharide; De, derived decidua; Jz, junctional zone; Lz, labyrinth zones; RIP, RNA Binding Protein Immunoprecipitation; Co-IP, Co-Immunoprecipitation; RPISeq, RNA-Protein Interaction Prediction.

Association of Genetic Polymorphisms in Long Noncoding RNA HOTTIP with Risk of Idiopathic Recurrent Spontaneous Abortion

The clustered homeobox gene family known as the Hox family plays a fundamental role in the morphogenesis of the vertebrate's embryo. A long noncoding RNA (lncRNA), known as HOTTIP (HOXA transcript at the distal tip), has been functionally characterized and contributed to the pathogenesis of various conditions. The current case-control study was undertaken to examine the gene frequencies and shared alleles of the HOTTIP  gene in Iranian participants with or without idiopathic recurrent spontaneous abortion (RSA). Both ARMS-PCR reaction and RFLP-PCR techniques were employed to detect three HOTTIP polymorphisms (rs2023843C/T, rs78248039A/T, and rs1859168C/A) in a DNA sample of 161 women with RSA and 177 healthy women. We found that the TT genotype of the HOTTIP rs2023843 C/T polymorphism was associated with a lower risk for idiopathic RSA. In contrast, the TT genotype of the HOTTIP rs78248039 A/T polymorphism was correlated with an enhanced risk of RSA. The presence of the A-allele for HOTTIP rs1859168 C/A polymorphism was associated with an increased risk for idiopathic RSA. Haplotype analysis showed that the T/T/A, C/T/A, T/T/C, and T/A/A haplotypes of rs2023843/rs78248039/rs1859168 enhanced RSA susceptibility. Computational analysis predicted that this lncRNA might act as a potential sponge for some microRNAs; therefore, affecting the expression of genes being targeted by them. In addition, both rs2023843 and rs1859168 variants could alter the local secondary structure of HOTTIP. Our results showed that HOTTIP rs2023843C/T, rs78248039A/T, and rs1859168C/A polymorphisms may confer genetic susceptibility to idiopathic RSA in an Iranian population.

Immunologic insights in recurrent spontaneous abortion: Molecular mechanisms and therapeutic interventions

Recurrent spontaneous abortion refers to the occurrence of two or more spontaneous abortions before or during the early stages of pregnancy. The immune system plays a crucial role in the maintenance of pregnancy and embryo implantation. Various immune cells, cytokines, and immune regulatory pathways are involved in the complex immune balance required for a stable pregnancy. Studies suggest that immune abnormalities may be associated with some recurrent spontaneous abortion cases, particularly those involving the dysregulation of immune cell function, autoimmune responses, and placental immunity. In terms of treatment, interventions targeting immune mechanisms are crucial. Various therapeutic approaches, including immunomodulatory drugs, immunoadsorption therapies, and immunocellular therapies, are continually being researched and developed. These approaches aim to restore the immune balance, enhance the success rate of pregnancies, and provide more effective treatment options for patients with recurrent spontaneous abortion.

The effect of Toxoplasma gondii infection on galectin-9 expression in decidual macrophages contributing to dysfunction of decidual NK cells during pregnancy

BACKGROUND

Toxoplasma gondii infection causes adverse pregnancy outcomes by affecting the expression of immunotolerant molecules in decidual immune cells. Galectin-9 (Gal-9) is widely expressed in decidual macrophages (dMφ) and is crucial for maintaining normal pregnancy by interacting with the immunomodulatory protein T-cell immunoglobulin and mucin domain-containing molecule 3 (Tim-3). However, the effects of T. gondii infection on Gal-9 expression in dMφ, and the impact of altered Gal-9 expression levels on the maternal-fetal tolerance function of decidual natural killer (dNK) cells, are still unknown.

METHODS

Pregnancy outcomes of T. gondii-infected C57BL/6 and Lgals9-/- pregnant mice models were recorded. Expression of Gal-9, c-Jun N-terminal kinase (JNK), phosphorylated JNK (p-JNK), and Forkhead box protein O1 (FOXO1) was detected by western blotting, flow cytometry or immunofluorescence. The binding of FOXO1 to the promoter of Lgals9 was determined by chromatin immunoprecipitation-polymerase chain reaction (ChIP-PCR). The expression of extracellular signal-regulated kinase (ERK), phosphorylated ERK (p-ERK), cAMP-response element binding protein (CREB), phosphorylated CREB (p-CREB), T-box expressed in T cells (T-bet), interleukin 10 (IL-10), and interferon gamma (IFN-γ) in dNK cells was assayed by western blotting.

RESULTS

Toxoplasma gondii infection increased the expression of p-JNK and FOXO1 in dMφ, resulting in a reduction in Gal-9 due to the elevated binding of FOXO1 with Lgals9 promoter. Downregulation of Gal-9 enhanced the phosphorylation of ERK, inhibited the expression of p-CREB and IL-10, and promoted the expression of T-bet and IFN-γ in dNK cells. In the mice model, knockout of Lgals9 aggravated adverse pregnancy outcomes caused by T. gondii infection during pregnancy.

CONCLUSIONS

Toxoplasma gondii infection suppressed Gal-9 expression in dMφ by activating the JNK/FOXO1 signaling pathway, and reduction of Gal-9 contributed to dysfunction of dNK via Gal-9/Tim-3 interaction. This study provides new insights for the molecular mechanisms of the adverse pregnancy outcomes caused by T. gondii.

Effect of bromodomain PHD-finger transcription factor (BPTF) on trophoblast epithelial-to-mesenchymal transition

The trophoblast epithelial-to-mesenchymal transition (EMT) is a procedure related to embryo implantation, spiral artery establishment and fetal-maternal communication, which is a key event for successful pregnancy. Inadequate EMT is one of the pathological mechanisms of recurrent miscarriage (RM). Whole-exome sequencing revealed that the mutation of bromodomain PHD-finger transcription factor (BPTF) was strongly associated with RM. In the present study, the effects of BPTF on EMT and the underlying mechanism were investigated. We found that the expression of BPTF in the villi of RM patients was significantly downregulated. Gene Ontology (GO) analysis revealed that BPTF participated in cell adhesion. The knockdown of BPTF prevented EMT and attenuated trophoblast invasion in vitro. BPTF activated Slug transcription by binding directly to the promoter region of the Slug gene. Interestingly, the protein levels of both Slug and BPTF were decreased in the villous cytotrophoblasts (VCTs) of RM villi. In conclusion, BPTF participates in the regulation of trophoblast EMT by activating Slug expression, suggesting that BPTF defects are an important factor in RM pathogenesis.

Isl Identifies the Extraembryonic Mesodermal/Allantois Progenitors and is Required for Placenta Morphogenesis and Vasculature Formation

The placenta links feto-maternal circulation for exchanges of nutrients, gases, and metabolic wastes between the fetus and mother, being essential for pregnancy process and maintenance. The allantois and mesodermal components of amnion, chorion, and yolk sac are derived from extraembryonic mesoderm (Ex-Mes), however, the mechanisms contributing to distinct components of the placenta and regulation the interactions between allantois and epithelium during chorioallantoic fusion and labyrinth formation remains unclear. Isl1 is expressed in progenitors of the Ex-Mes and allantois the Isl1 mut mouse line is analyzed to investigate contribution of Isl1+ Ex-Mes / allantoic progenitors to cells of the allantois and placenta. This study shows that Isl1 identifies the Ex-Mes progenitors for endothelial and vascular smooth muscle cells, and most of the mesenchymal cells of the placenta and umbilical cord. Deletion of Isl1 causes defects in allantois growth, chorioallantoic fusion, and placenta vessel morphogenesis. RNA-seq and CUT&Tag analyses revealed that Isl1 promotes allantoic endothelial, inhibits mesenchymal cell differentiation, and allantoic signals regulated by Isl1 mediating the inductive interactions between the allantois and chorion critical for chorionic epithelium differentiation, villous formation, and labyrinth angiogenesis. This study above reveals that Isl1 plays roles in regulating multiple genetic and epigenetic pathways of vascular morphogenesis, provides the insight into the mechanisms for placental formation, highlighting the necessity of Isl1 for placenta formation/pregnant maintenance.

Comprehensive review for non-coding RNAs: From mechanisms to therapeutic applications

Non-coding RNAs (ncRNAs) are an assorted collection of transcripts that are not translated into proteins. Since their discovery, ncRNAs have gained prominence as crucial regulators of various biological functions across diverse cell types and tissues, and their abnormal functioning has been implicated in disease. Notably, extensive research has focused on the relationship between microRNAs (miRNAs) and human cancers, although other types of ncRNAs, such as long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs), are also emerging as significant contributors to human disease. In this review, we provide a comprehensive summary of our current knowledge regarding the roles of miRNAs, lncRNAs, and circRNAs in cancer and other major human diseases, particularly cancer, cardiovascular, neurological, and infectious diseases. Moreover, we discuss the potential utilization of ncRNAs as disease biomarkers and as targets for therapeutic interventions.

Cytochrome c oxidase IV isoform 1 (COX4-1) regulates the proliferation, migration and invasion of trophoblast cells via modulating mitochondrial function

INTRODUCTION

Spontaneous miscarriage is a common complication of early pregnancy. Previous studies have shown that mitochondrial function plays an important role in establishment of a successful pregnancy. Cytochrome c oxidase subunit 4 isoform 1 (COX4I1), a component of electron transport chain complex Ⅳ, is required for coupling the rate of ATP production to energetic requirements. However, there is very limited research on its role in trophoblast biology and how its dysfunction may contribute to spontaneous miscarriage.

METHODS

Placental villi (7-10 weeks gestational age) collected from either induced termination of pregnancy or after spontaneous miscarriage were examined for expression of COX4I1. COX4I1 was knocked down by siRNA transfection of primary isolates of EVT cells. Real-time cell analysis (RTCA) and 5-Ethynyl-2'-deoxyuridine (EdU) were used to detect changes in proliferation ability after COX4I1 knockdown of EVT cells. Migration and invasion indices were determined by RTCA. Mitochondrial morphology was observed via MitoTracker staining. Oxidative phosphorylation, ATP production, and glycolysis in COX4I1-deficient cells and controls were assessed by a cellular energy metabolism analyzer (Seahorse).

RESULTS

In placental villous tissue, COX4I1 expression was significantly decreased in the spontaneous miscarriage group. Knockdown of COX4I1 inhibited EVT cell proliferation, increased the migration and invasion ability and mitochondrial fusion of EVT cells. Mitochondrial respiration and glycolysis were impaired in COX4I1-deficient EVT cells. Knockdown of MMP1 could rescue the increased migration and invasion induced by COX4I1 silencing.

DISCUSSION

Low expression of COX4I1 leads to mitochondrial dysfunction in EVT, resulting in altered trophoblast function, and ultimately to pregnancy loss.

Decidual macrophage: a reversible role in immunotolerance between mother and fetus during pregnancy

The tolerance of the semi-allogeneic fetus by the maternal immune system is an eternal topic of reproductive immunology for ensuring a satisfactory outcome. The maternal-fetal interface serves as a direct portal for communication between the fetus and the mother. It is composed of placental villi trophoblast cells, decidual immune cells, and stromal cells. Decidual immune cells engage in maintaining the homeostasis of the maternal-fetal interface microenvironment. Furthermore, growing evidence has shown that decidual macrophages play a crucial role in maternal-fetal tolerance during pregnancy. As the second largest cell population among decidual immune cells, decidual macrophages are divided into two subtypes: classically activated macrophages (M1) and alternatively activated macrophages (M2). M2 polarization is critical for placentation and embryonic development. Cytokines, exosomes, and metabolites regulate the polarization of decidual macrophages, and thereby modulate maternal-fetal immunotolerance. Explore the initial relationship between decidual macrophages polarization and maternal-fetal immunotolerance will help diagnose and treat the relevant pregnancy diseases, reverse the undesirable outcomes of mothers and infants.

Deciphering the Epigenetic Landscape: Placental Development and Its Role in Pregnancy Outcomes

The placenta stands out as a unique, transitory, and multifaceted organ, essential to the optimal growth and maturation of the fetus. Functioning as a vital nexus between the maternal and fetal circulatory systems, it oversees the critical exchange of nutrients and waste. This exchange is facilitated by placental cells, known as trophoblasts, which adeptly invade and remodel uterine blood vessels. Deviations in placental development underpin a slew of pregnancy complications, notably fetal growth restriction (FGR), preeclampsia (PE), recurrent spontaneous abortions (RSA), and preterm birth. Central to placental function and development is epigenetic regulation. Despite its importance, the intricate mechanisms by which epigenetics influence the placenta are not entirely elucidated. Recently, the scientific community has turned its focus to parsing out the epigenetic alterations during placental development, such as variations in promoter DNA methylation, genomic imprints, and shifts in non-coding RNA expression. By establishing correlations between epigenetic shifts in the placenta and pregnancy complications, researchers are unearthing invaluable insights into the biology and pathophysiology of these conditions. This review seeks to synthesize the latest findings on placental epigenetic regulation, spotlighting its crucial role in shaping fetal growth trajectories and development. Through this lens, we underscore the overarching significance of the placenta in the larger narrative of gestational health.

JPT2 Affects Trophoblast Functions and Macrophage Polarization and Metabolism, and Acts as a Potential Therapeutic Target for Recurrent Spontaneous Abortion

Recurrent spontaneous abortion (RSA) is a pregnancy-related condition with complex etiology. Trophoblast dysfunction and abnormal macrophage polarization and metabolism are associated with RSA; however, the underlying mechanisms remain unknown. Jupiter microtubule-associated homolog 2 (JPT2) is essential for calcium mobilization; however, its role in RSA remains unclear. In this study, it is found that the expression levels of JPT2, a nicotinic acid adenine dinucleotide phosphate-binding protein, are decreased in the villous tissues of patients with RSA and placental tissues of miscarried mice. Mechanistically, it is unexpectedly found that abnormal JPT2 expression regulates trophoblast function and thus involvement in RSA via c-Jun N-terminal kinase (JNK) signaling, but not via calcium mobilization. Specifically, on the one hand, JPT2 deficiency inhibits trophoblast adhesion, migration, and invasion by inhibiting the JNK/atypical chemokine receptor 3 axis. On the other hand, trophoblast JPT2 deficiency contributes to M1 macrophage polarization by promoting the accumulation of citrate and reactive oxygen species via inhibition of the JNK/interleukin-6 axis. Self-complementary adeno-associated virus 9-JPT2 treatment alleviates embryonic resorption in abortion-prone mice. In summary, this study reveals that JPT2 mediates the remodeling of the immune microenvironment at the maternal-fetal interface, suggesting its potential as a therapeutic target for RSA.

ROS-driven supramolecular nanoparticles exhibiting efficient drug delivery for chemo/Chemodynamic combination therapy for Cancer treatment

Drug-based supramolecular self-assembling delivery systems have enhanced the bioavailability of chemotherapeutic drugs and reduced systemic side effects; however, improving the delivery efficiency and responsive release ability of these systems remains challenging. This study focuses primarily on the utilization of per-6-thio-β-cyclodextrin (CD) to link a significant quantity of paclitaxel (PTX) via ROS-sensitive thioketal (TK) linkages (designated as CDTP), thereby allowing efficiently drug release when exposed to high levels of reactive oxygen species (ROS) in the tumor microenvironment. To construct these supramolecular nanoparticles (NPs) with CDTP, we introduced PEGylated ferrocene (Fc) through host-guest interactions. The intracellular hydrogen peroxide (H2O2) is converted into hydroxyl radicals (•OH) through the Fc-catalyzed Fenton reaction. Additionally, the generated Fc+ consumes the antioxidant glutathione (GSH). In both in vivo and in vitro experiments, CDTP@Fc-PEG NPs were absorbed effectively by tumor cells, which increased levels of ROS and decreased levels of GSH, disrupting the redox balance of cancer cells and increasing their sensitivity to chemotherapy. Furthermore, CDTP@Fc-PEG NPs exhibited high tumor accumulation and cytotoxicity without causing significant toxicity to healthy organs. Collectively, our results suggest CDTP@Fc-PEG NPs as a promising supramolecular nano-delivery platform for high drug-loading of PTX and synergistic chemotherapy.

The role of extracellular vesicles from placenta and endometrium in pregnancy: Insights from tumor biology

Extracellular vesicles (EVs) are small membrane-bound particles secreted by various cell types that play a critical role in intercellular communication by packaging and delivering biomolecules. In recent years, EVs have emerged as essential messengers in mediating physiological and pathological processes in tumor biology. The tumor microenvironment (TME) plays a pivotal role in tumor generation, progression, and metastasis. In this review, we provide an overview of the impact of tumor-derived EVs on both tumor cells and the TME. Moreover, we draw parallels between tumor biology and pregnancy, as successful embryo implantation also requires intricate intercellular communication between the placental trophecepiblast and the endometrial epithelium. Additionally, we discuss the involvement of EVs in targeting immune responses, trophoblast invasion, migration, and angiogenesis, which are shared biological processes between tumors and pregnancy. Specifically, we highlight the effects of placenta-derived EVs on the fetal-maternal interface, placenta, endometrium, and maternal system, as well as the role of endometrium-derived EVs in embryo-endometrial communication. However, challenges still exist in EVs research, including the standardization of EVs isolation methods for diagnostic testing, which also apply to reproductive systems where EVs-mediated communication is proposed to take place. Through this review, we aim to deepen the understanding of EVs, particularly in the context of reproductive biology, and encourage further investigation in this field.

Non-coding RNA regulates the immune microenvironment in recurrent spontaneous abortion (RSA): new insights into immune mechanisms†

Recurrent spontaneous abortion (RSA) has various causes, including chromosomal abnormalities, prethrombotic state, and abnormal uterine anatomical factors. However, the pathogenesis of RSA is still unclear. Surprisingly, non-coding RNA can stably express at the maternal-fetal interface and regulate immune cells' proliferation, apoptosis, invasion, metastasis, and angiogenesis. Accumulating evidence suggests that the competing endogenous RNA (ceRNA) regulatory network between non-coding RNAs complicates RSA's pathological process and maybe a new starting point for exploring RSA. In this review, we mainly discuss the regulatory network and potential significance of non-coding RNA in the immune microenvironment of RSA patients. In addition, the cellular interactions of non-coding RNA transported through vesicles were introduced from aspects of trophoblast function and immune regulation. Finally, we analyze previous studies and further discuss that the stable expression of non-coding RNA may be used as a biomarker of some disease states and a prediction target of RSA.

Exosome-delivered miR-410-3p reverses epithelial-mesenchymal transition, migration and invasion of trophoblasts in spontaneous abortion

Current studies have indicated that insufficient trophoblast epithelial-mesenchymal transition (EMT), migration and invasion are crucial for spontaneous abortion (SA) occurrence and development. Exosomal miRNAs play significant roles in embryonic development and cellular communication. Hereon, we explored the roles of serum exosomes derived from SA patients on trophoblast EMT, migration and invasion. Exosomes were isolated from normal control (NC) patients with abortion for unplanned pregnancy and SA patients, then characterized by transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA) and western blotting. Exosomal miRNA profiles were identified by miRNA sequencing. The effects of serum exosomes on trophoblast migration and invasion were detected by scratch wound healing and transwell assays, and other potential mechanisms were revealed by quantitative real-time PCR (RT-PCR), western blotting and dual-luciferase reporter assay. Finally, animal experiments were used to explore the effects of exosomal miR-410-3p on embryo absorption in mice. The serum exosomes from SA patients inhibited trophoblast EMT and reduced their migration and invasion ability in vitro. The miRNA sequencing showed that miR-410-3p was upregulated in SA serum exosomes. The functional experiments showed that SA serum exosomes restrained trophoblast EMT, migration and invasion by releasing miR-410-3p. Mechanistically, SA serum exosomal miR-410-3p inhibited trophoblast cell EMT, migration and invasion by targeting TNF receptor-associated factor 6 (TRAF6) at the post-transcriptional level. Besides, SA serum exosomal miR-410-3p inhibited the p38 MAPK signalling pathway by targeting TRAF6 in trophoblasts. Moreover, milk exosomes loaded with miR-410-3p mimic reached the maternal-fetal interface and aggravated embryo absorption in female mice. Clinically, miR-410-3p and TRAF6 expression were abnormal and negatively correlated in the placental villi of SA patients. Our findings indicated that exosome-derived miR-410-3p plays an important role between SA serum and trophoblasts in intercellular communication, suggesting a novel mechanism by which serum exosomal miRNA regulates trophoblasts in SA patients.

Polystyrene Nanoplastics Activate Autophagy and Suppress Trophoblast Cell Migration/Invasion and Migrasome Formation to Induce Miscarriage

Nanoplastics (NPs), as emerging pollutants, have attracted global attention. Nevertheless, the adverse effects of NPs on female reproductive health, especially unexplained miscarriage, are poorly understood. Defects of trophoblast cell migration and invasion are associated with miscarriage. Migrasomes were identified as cellular organelles with largely unidentified functions. Whether NPs might affect migration, invasion, and migrasome formation and induce miscarriage has been completely unexplored. In this study, we selected polystyrene nanoplastics (PS-NPs, 50 nm) as a model of plastic particles and treated human trophoblast cells and pregnant mice with PS-NPs at doses near the actual environmental exposure doses of plastic particles in humans. We found that exposure to PS-NPs induced a pregnant mouse miscarriage. PS-NPs suppressed ROCK1-mediated migration/invasion and migrasome formation. SOX2 was identified as the transcription factor of ROCK1. PS-NPs activated autophagy and promoted the autophagy degradation of SOX2, thus suppressing SOX2-mediated ROCK1 transcription. Supplementing with murine SOX2 or ROCK1 could efficiently rescue migration/invasion and migrasome formation and alleviate miscarriage. Analysis of the protein levels of SOX2, ROCK1, TSPAN4, NDST1, P62, and LC-3BII/I in PS-NP-exposed trophoblast cells, villous tissues of unexplained miscarriage patients, and placental tissues of PS-NP-exposed mice gave consistent results. Collectively, this study revealed the reproductive toxicity of nanoplastics and their potential regulatory mechanism, indicating that NP exposure is a risk factor for female reproductive health.

Non-coding RNAs in Recurrent implantation failure

Recurrent implantation failure (RIF), defined as the inability to achieve conception following multiple consecutive in-vitro fertilization (IVF) attempts, represents a complex and multifaceted challenge in reproductive medicine. The emerging role of non-coding RNAs in RIF etiopathogenesis has only gained prominence over the last decade, illustrating a new dimension to our understanding of the intricate network underlying RIF. Successful embryo implantation demands a harmonious synchronization between an adequately decidualized endometrium, a competent blastocyst, and effective maternal-embryonic interactions. Emerging evidence has clarified the involvement of a sophisticated network of non-coding RNAs, including microRNAs, circular RNAs, and long non-coding RNAs, in orchestrating these pivotal processes. Disconcerted expression of these molecules can disrupt the delicate equilibrium required for implantation, amplifying the risk of RIF. This comprehensive review presents an in-depth investigation of the complex role played by non-coding RNAs in the pathogenesis of RIF. Furthermore, it underscores the vast potential of non-coding RNAs as diagnostic biomarkers and therapeutic targets, with the ultimate goal of enhancing implantation success rates in IVF cycles. As ongoing research continues to unravel the intercalated web of molecular interactions, exploiting the power of non-coding RNAs may offer promising avenues for mitigating the challenges posed by RIF and improving the outcomes of assisted reproduction.

Trophoblast-derived miR-410-5p induces M2 macrophage polarization and mediates immunotolerance at the fetal-maternal interface by targeting the STAT1 signaling pathway

BACKGROUND

Macrophages phenotypic deviation and immune imbalance play vital roles in pregnancy-associated diseases such as spontaneous miscarriage. Trophoblasts regulate phenotypic changes in macrophages, however, their underlying mechanism during pregnancy remains unclear. Therefore, this study aimed to elucidate the potential function of trophoblast-derived miRNAs (miR-410-5p) in macrophage polarization during pregnancy.

METHODS

Patient decidual macrophage tissue samples in spontaneous abortion group and normal pregnancy group (those who had induced abortion for non-medical reasons) were collected at the Reproductive Medicine Center of Renmin Hospital of Wuhan University from April to December 2021. Furthermore, placental villi and decidua tissue samples were collected from patients who had experienced a spontaneous miscarriage and normal pregnant women for validation and subsequent experiments at the Shenzhen Zhongshan Obstetrics & Gynecology Hospital (formerly Shenzhen Zhongshan Urology Hospital), from March 2021 to September 2022. As an animal model, 36 female mice were randomly divided into six groups as follows: naive-control, lipopolysaccharide-model, agomir-negative control prevention, agomir-410-5p prevention, agomir-negative control treatment, and agomir-410-5p treatment groups. We analyzed the miR-410-5p expression in abortion tissue and plasma samples; and supplemented miR-410-5p to evaluate embryonic absorption in vivo. The main source of miR-410-5p at the maternal-fetal interface was analyzed, and the possible target gene, signal transducer and activator of transcription (STAT) 1, of miR-410-5p was predicted. The effect of miR-410-5p and STAT1 regulation on macrophage phenotype, oxidative metabolism, and mitochondrial membrane potential was analyzed in vitro.

RESULTS

MiR-410-5p levels were lower in the spontaneous abortion group compared with the normal pregnancy group, and plasma miR-410-5p levels could predict pregnancy and spontaneous abortion. Prophylactic supplementation of miR-410-5p in pregnant mice reduced lipopolysaccharide-mediated embryonic absorption and downregulated the decidual macrophage pro-inflammatory phenotype. MiR-410-5p were mainly distributed in villi, and trophoblasts secreted exosomes-miR-410-5p at the maternal-fetal interface. After macrophages captured exosomes, the cells shifted to the tolerance phenotype. STAT1 was a potential target gene of miR-410-5p. MiR-410-5p bound to STAT1 mRNA, and inhibited the expression of STAT1 protein. STAT1 can drive macrophages to mature to a pro-inflammatory phenotype. MiR-410-5p competitive silencing of STAT1 can avoid macrophage immune disorders.

CONCLUSION

MiR-410-5p promotes M2 macrophage polarization by inhibiting STAT1, thus ensuring a healthy pregnancy. These findings are of great significance for diagnosing and preventing spontaneous miscarriage, providing a new perspective for further research in this field.

miR-146b-5p downregulates IRAK1 and ADAM19 to suppress trophoblast proliferation, invasion, and migration in miscarriage†

A large proportion of miscarriages are classified as unexplained miscarriages since no cause is identified. No reliable biomarkers or treatments are available for these pregnancy losses. While our transcriptomic sequencing has revealed substantial upregulation of miR-146b-5p in unexplained miscarriage villous tissues, its role and associated molecular processes have yet to be fully characterized. Our work revealed that relative to samples from normal pregnancy, miR-146b-5p was significantly elevated in villous tissues from unexplained miscarriage patients and displayed promising diagnostic potential. Moreover, miR-146b-5p agomir contributed to higher rates of embryonic resorption in ICR mice. When overexpressed in HTR-8/SVneo cells, miR-146b-5p attenuated the proliferative, invasive, and migratory activity of these cells while suppressing the expression of MMP9 and immune inflammation-associated cytokines, including IL1B, IL11, CXCL1, CXCL8, and CXCL12. Conversely, inhibition of its expression enhanced proliferation, migration, and invasion abilities. Mechanistically, IL-1 receptor-associated kinase-1 and a disintegrin and metalloproteinase 19 were identified as miR-146b-5p targets regulating trophoblast function, and silencing IL-1 receptor-associated kinase-1 had similar effects as miR-146b-5p overexpression, while IL-1 receptor-associated kinase-1 overexpression could partially reverse the inhibitory impact of this microRNA on trophoblasts. miR-146b-5p may inhibit trophoblast proliferation, migration, invasion, and implantation-associated inflammation by downregulating IL-1 receptor-associated kinase-1 and a disintegrin and metalloproteinase 19, participating in the pathogenesis of miscarriage and providing a critical biomarker and a promising therapeutic target for unexplained miscarriage.

LncRNA AOC4P recruits TRAF6 to regulate EZH2 ubiquitination and participates in trophoblast glycolysis and M2 macrophage polarization which is associated with recurrent spontaneous abortion

During embryo implantation, trophoblast cells rely on large amounts of energy produced by glycolysis for their rapid growth and invasion. The disorder of trophoblast metabolism may lead to recurrent spontaneous abortion (RSA). Lactate, which is produced by the glycolysis of trophoblast cells during early pregnancy, can promote the polarization of M2 macrophages and maintain an anti-inflammatory environment at the maternal-fetal interface. Our study found that amine oxidase copper-containing 4 pseudogene (AOC4P) was abnormally increased in villi from RSA patients. It inhibited the glycolysis of trophoblast cells and thus hindered the polarization of M2 macrophages. Further studies showed that AOC4P combines with tumor necrosis factor receptor-associated factor 6 (TRAF6) to upregulate TRAF6 expression. TRAF6 acted as an E3 ubiquitin ligase to promote ubiquitination and degradation of zeste homolog 2 (EZH2). These results provided new insights into the important role played by AOC4P at the maternal-fetal interface.

microRNA-92b-3p augments colon cancer development through inhibiting KLF3

Colon cancer (CC) is a tumor of the large intestine. miR-92b-3p is often deregulated in the tumorigensis. Here, the role of miR-92b-3p in the development of CC was investigated. miR-92b-3p and Kruppel-like factor 3 (KLF3) expression was examined in CC tissues and cells. miR-92b-3p inhibitor or KLF3 overexpression vector was transfected into CC cells, respectively to observe its role in CC cell proliferation, invasion, migration, and apoptosis. The targeting relationship between miR-92b-3p and KLF3 was validated. Meanwhile, rescue experiments were performed by co-transfection of miR-92b-3p inhibitor and KLF3 siRNA, followed by determining CC cell proliferation, invasion, migration, and apoptosis. Higher miR-92b-3p and lower KLF3 expression levels were observed in CC tissues and cells. miR-92b-3p inhibition or KLF3 overexpression reduced proliferation, invasion, and migration whereas induced apoptosis of CC cells. KLF3 was validated to be the target gene of miR-92b-3p. Depletion of KLF3 could reverse the antitumor role of miR-92b-3p inhibition in CC cells. miR-92b-3p augments CC development through inhibiting KLF3, which may confers a novel way to develop future treatment target.

Aquaporin 9 causes recurrent spontaneous abortion by inhibiting trophoblast cell epithelial-mesenchymal transformation and invasion through the PI3K/AKT pathway†

BACKGROUND

Invasion of the endometrium by trophoblast cells is a key event during pregnancy, although the underlying mechanism remains unclear. Aquaporin 9 (AQP 9) is expressed in many eukaryotes and is associated with cell invasion. The objective of this study was to evaluate the significance of AQP9 in recurrent spontaneous abortion.

METHODS

We screened the GSE22490 dataset and further differentiated aquaporin 9 expression in villi. AQP9 was evaluated as one of the key factors in abortion by injecting AQP9 overexpressed plasmid into the uterus of CD1 mice. Trophoblast cells were transfected with AQP9-overexpressing plasmid or siAQP9 to measure cell proliferation, migration, invasion, and apoptosis. Western blot was used to measure changes in the expression of invasion, epithelial-mesenchymal transformation process, and PI3K/AKT pathway. Finally, the role of AQP9 in PI3K/AKT signaling pathway was determined using the PI3K/AKT inhibitor, LY294002, and activator, 740Y-P.

RESULTS

AQP9 is highly expressed in recurrent spontaneous abortion villus. Intrauterine injections of AQP9-overexpressing plasmid into CD1 mice resulted in atrophy and blackness of the gestational sac and increased the absorption rate, it is the causative factor of abortion. AQP9 upregulation inhibited the proliferation, invasion, migration, and epithelial-mesenchymal transformation process in vitro of trophoblast cells and increased cell apoptosis. The opposite result was observed after silencing AQP9. AQP9 overexpression also inhibited the PI3K/AKT pathway. LY294002 and 740Y-P partially recovered AQP9-induced trophoblast invasion and migration via the PI3K/AKT pathway.

CONCLUSIONS

AQP9 reduces the invasive ability of trophoblast cells by regulating PI3K/AKT signaling pathway, participating in recurrent spontaneous abortion.

CTRP6 regulates M1 macrophage polarization via the PPAR-γ/NF-κB pathway and reprogramming glycolysis in recurrent spontaneous abortion

Aberrant polarization and functions of decidual macrophages are closely related to recurrent spontaneous abortion (RSA). C1q/tumor necrosis factor-related protein 6 (CTRP6) is a member of the adiponectin paralog family, and plays indispensable roles in inflammation, glucose uptake and tumor metastasis. However, the regulatory effect of CTRP6 on macrophage polarization and glycolysis in RSA and the underlying mechanisms have not been fully elucidated. In the present study, we first found that CTRP6 expression was positively correlated with the M1 macrophage marker (CD86) in decidual tissues by dual immunofluorescence analysis. In vitro experiments indicated that CTRP6 could facilitate M1 macrophage activation through the PPAR-γ/NF-κB pathway and manipulate the glycolysis of macrophages. Notably, in addition to silencing CTRP6, treatment with a PPAR-γ agonist (GW1929) inhibited M1 macrophage polarization and rescued embryo absorption in vivo. Taken together, these results identify previously unrevealed functions of CTRP6 in macrophage transformation during RSA.

MicroRNAs in idiopathic inflammatory myopathies: state-of-the-art and future perspectives

PURPOSE OF REVIEW

Idiopathic inflammatory myopathies (IIMs) are a group of rare autoimmune disorders characterized by muscle weakness and inflammation. MicroRNAs (miRNAs) are the main class of small noncoding RNAs regulating a wide range of physiological and pathological processes and play a role in mediating autoimmunity and inflammation. In this review, we summarize the latest knowledge on the role of miRNAs in systemic autoimmune diseases with particular focus on IIMs.

RECENT FINDINGS

Study on miRNA expression in IIMs is helping in understanding the pathogenetic basis of the disease at a tissue and systemic level. Several miRNAs, even with a muscle-specific expression (myomiRs), have been shown to be involved in immune and nonimmune mechanisms of myofiber damage. MiRNAs modulate and orchestrate the local inflammatory infiltrate and could be used as potential biomarkers as they correlate with disease activity and response to therapy.

SUMMARY

IIMs comprise different clinical phenotypes and still little is known about the molecular signature of each subset. Further research about miRNA profiling will provide additional insights in the disease characterization with an expected impact on the therapeutic strategies.

Dysregulated miRNAs in recurrent miscarriage: A systematic review

Recurrent miscarriage (RM) is a complex reproductive medicine disease that affects many families. The cause of RM is unclear at this time; however, lifestyle and genetic variables may influence the process. The slight alteration in miRNA expression has enormous consequences for a variety of difficulties, one of which may be RM. The target of this systematic study was to provide a framework of the dysregulated miRNAs in RM. The Prisma guidelines were applied to perform current systematic review pertaining to articles in the seven databases. Thirty-nine papers out of 245 received fulfilled all inclusion requirements. From all the mentioned miRNAs, 40 were up-regulated (65.57 %), whereas 21 were down-regulated (34.43 %). These dysregulated miRNAs contributed to the pathophysiology of RM by influencing key pathways and processes such as apoptosis, angiogenesis, epithelial-mesenchymal transition, and the immune system. Understanding the dysregulation of miRNAs, as well as the pathways and processes that engage these miRNAs and impact disease pathogenesis, may aid in clarifying the unknown underlying mechanisms of RM and the development of novel molecular therapeutic targets and medical domains.

Engineered extracellular vesicles in female reproductive disorders

Biologically active and nanoscale extracellular vesicles (EVs) participate in a variety of cellular physiological and pathological processes in a cell-free manner. Unlike cells, EVs not only do not cause acute immune rejection, but are much smaller and have a low risk of tumorigenicity or embolization. Because of their unique advantages, EVs show promise in applications in the diagnosis and treatment of reproductive disorders. As research broadens, engineering strategies for EVs have been developed, and engineering strategies for EVs have substantially improved their application potential while circumventing the defects of natural EVs, driving EVs toward clinical applications. In this paper, we will review the engineering strategies of EVs, as well as their regulatory effects and mechanisms on reproductive disorders (including premature ovarian insufficiency (POI), polycystic ovarian syndrome (PCOS), recurrent spontaneous abortion (RSA), intrauterine adhesion (IUA), and endometriosis (EMS)) and their application prospects. This work provides new ideas for the treatment of female reproductive disorders by engineering EVs.

Trophoblast Cell Function in the Antiphospholipid Syndrome

Antiphospholipid syndrome (APS) is a complex thrombo-inflammatory autoimmune disease characterized by the presence of antiphospholipid antibodies (aPL). Women with APS are at high risk of recurrent early pregnancy loss as well as late obstetrical complications-premature birth due to placental insufficiency or severe preeclampsia. Accumulating evidence implies that vascular thrombosis is not the only pathogenic mechanism in obstetric APS, and that the direct negative effect of aPL on the placental cells, trophoblast, plays a major role. In this review, we summarize the current findings regarding the potential mechanisms involved in aPL-induced trophoblast dysfunction. Introduction on the APS and aPL is followed by an overview of the effects of aPL on trophoblast-survival, cell function and aPL internalization. Finally, the implication of several non-coding RNAs in pathogenesis of obstetric APS is discussed, with special emphasis of their possible role in trophoblast dysfunction and the associated mechanisms.

Dominoes with interlocking consequences triggered by zinc: involvement of microelement-stimulated MSC-derived exosomes in senile osteogenesis and osteoclast dialogue

As societal aging intensifies, senile osteoporosis has become a global public health concern. Bone microdamage is mainly caused by processes such as enhancing osteoclast activity or reducing bone formation by osteoblast-lineage cells. Compared with young individuals, extracellular vesicles derived from senescent bone marrow mesenchymal stem cells(BMSCs) increase the transient differentiation of bone marrow monocytes (BMMs) to osteoclasts, ultimately leading to osteoporosis and metal implant failure. To address this daunting problem, an exosome-targeted orthopedic implant composed of a nutrient coating was developed. A high-zinc atmosphere used as a local microenvironmental cue not only could inhibit the bone resorption by inhibiting osteoclasts but also could induce the reprogramming of senile osteogenesis and osteoclast dialogue by exosome modification. Bidirectional regulation of intercellular communication via cargoes, including microRNAs carried by exosomes, was detected. Loss- and gain-of-function experiments demonstrated that the key regulator miR-146b-5p regulates the protein kinase B/mammalian target of rapamycin pathway by targeting the catalytic subunit gene of PI3K-PIK3CB. In vivo evaluation using a naturally-aged osteoporotic rat femoral defect model further confirmed that a nutrient coating substantially augments cancellous bone remodeling and osseointegration by regulating local BMMs differentiation. Altogether, this study not only reveals the close link between senescent stem cell communication and age-related osteoporosis but also provides a novel orthopedic implant for elderly patients with exosome modulation capability.

Effect of 2-deoxyglucose-mediated inhibition of glycolysis on migration and invasion of HTR-8/SVneo trophoblast cells

The proper invasion of trophoblasts is crucial for embryo implantation and placental development, which is helpful to establish a correct maternal-fetal relationship. Trophoblasts can produce a large amount of lactate through aerobic glycolysis during early pregnancy. Lactate creates a low pH microenvironment around the embryo to help uterine tissue decompose and promote the invasion of trophoblasts. The purpose of this study is to reveal the the potential mechanism of aerobic glycolysis regulating the invasiveness of trophoblasts by investigating the effect of 2-Deoxy-D-glucose (2-DG), a glycolysis inhibitor, on the biological function of HTR-8/SVneo trophoblast cells, the expressions of epithelial mesenchymal transformation (EMT) markers and invasion-related factors. 2-DG could inhibit the aerobic glycolysis of trophoblasts and decrease the activity of trophoblasts in a dose-dependent manner. Moreover, 2-DG inhibited the EMT of HTR-8/SVneo cells, down-regulated the expression of invasion-related factors matrix metalloproteinase 2/9 (MMP2/9) and up-regulated the expression of tissue inhibitor of matrix metalloproteinases 1/2 (TIMP1/2), thus inhibiting cell migration and invasion. This paper provides a foundation in the significance of aerobic glycolysis of trophoblasts in the process of invasion, and also provides ideas and insights for the promotion of embryo implantation.

ELF1/PRR11/ARP2/3 promoted trophoblast cells proliferation and motility in early pregnancy

BACKGROUND/OBJECTIVE

Early pregnancy loss (EPL) is a common adverse pregnancy outcome with an incidence of approximately 10-30%. There are many factors that cause EPL, among which the lack of proliferation and invasive properties of trophoblast cells can lead to embryonic development. Therefore, in this study, the molecular biology of trophoblast cells was investigated.

METHODS

Placental villous tissues from EPL patients were collected to explore ELF1 and PRR11 gene expression. The proliferation and migration of trophoblast cells were assessed by MTT, crystalline violet staining, and traswell assays, respectively. Western blotting and RT-qPCR were performed to investigate the relationship between ELF1, PRR11, and ARP2/3. F-actin polymerization and FAK activation were evaluated by immunofluorescence and western blotting. Ultimately, ELF1/PRR11/ARP2/3 expression was verified in the EPL mice model RESULTS: ELF1 and PRR11 were lowly expressed in placental villous tissues from EPL. The overexpression of ELF1 and PRR11 promoted proliferation and migration of trophoblast cells. Moreover, while ELF1 bound to the PRR11 promoter and promoted transcriptional activation. Finally, ELF1/PRR11/ARP2/3 showed low expression in the placental tissue of EPL mice.

CONCLUSION

Our study suggested that PRR11 promoted the motility of trophoblast cells by binding to the ARP2/3 complex to promote F-actin polymerization and FAK activation. In addition, ELF1 bound to the initiation site of PRR11 to promote its transcription. ELF1/PRR11/ARP2/3 may play an important role in EPL.

miR-526b-5p/c-Myc/Foxp1 participates in recurrent spontaneous abortion by regulating the proliferation, migration, and invasion of trophoblasts

PURPOSE

As a member of the C19MC family, miR-526b-5p is mainly expressed in the placental tissue and is a well-known tumor suppressor microRNA. However, its effect on the function of trophoblasts and its role in the development of recurrent spontaneous abortion (RSA) remains unclear.

METHODS

Transcriptome sequencing, quantitative real-time polymerase chain reaction (RT-qPCR), Western blot, 5-ethynyl-2'-deoxyuridine (Edu) proliferation analysis, cell counting kit-8 (CCK8) assay, Transwell assays, and wound healing were used to detect the proliferation, migration, and invasion capacity of trophoblasts. Target genes of miR-526b-5p were obtained by the dual luciferase reporter system. The promoter-reporter system and ChIP-qPCR were used to prove that c-Myc positively regulated the expression of Foxp1 RESULTS: The miR-526b-5p levels were significantly higher in patients with RSA than in controls. High expression of miR-526b-5p inhibited the proliferation, migration, and invasion of trophoblast cell line. By contrast, low expression of miR-526b-5p promoted the proliferation and migration of trophoblast cell line. Target genes of miR-526b-5p were c-Myc and Foxp1. c-Myc positively regulated the expression of Foxp1 by binding to the Foxp1 promoter location -146/-135. Finally, miR-526b-5p impeded the proliferation, migration, and invasion of trophoblasts by negatively regulating c-Myc by rescue experiments.

CONCLUSION

Thus, miR-526b-5p affected the proliferation, migration, and invasion of trophoblasts by targeting c-Myc and Foxp1. Low expression of c-Myc further deactivated the positive transcriptional regulation of c-Myc on Foxp1, which may be the mechanism of RSA. This study provides potential therapeutic targets and clues for the diagnosis and treatment of RSA.

First-Trimester Screening for Miscarriage or Stillbirth-Prediction Model Based on MicroRNA Biomarkers

We evaluated the potential of cardiovascular-disease-associated microRNAs to predict in the early stages of gestation (from 10 to 13 gestational weeks) the occurrence of a miscarriage or stillbirth. The gene expressions of 29 microRNAs were studied retrospectively in peripheral venous blood samples derived from singleton Caucasian pregnancies diagnosed with miscarriage (n = 77 cases; early onset, n = 43 cases; late onset, n = 34 cases) or stillbirth (n = 24 cases; early onset, n = 13 cases; late onset, n = 8 cases; term onset, n = 3 cases) and 80 selected gestational-age-matched controls (normal term pregnancies) using real-time RT-PCR. Altered expressions of nine microRNAs (upregulation of miR-1-3p, miR-16-5p, miR-17-5p, miR-26a-5p, miR-146a-5p, and miR-181a-5p and downregulation of miR-130b-3p, miR-342-3p, and miR-574-3p) were observed in pregnancies with the occurrence of a miscarriage or stillbirth. The screening based on the combination of these nine microRNA biomarkers revealed 99.01% cases at a 10.0% false positive rate (FPR). The predictive model for miscarriage only was based on the altered gene expressions of eight microRNA biomarkers (upregulation of miR-1-3p, miR-16-5p, miR-17-5p, miR-26a-5p, miR-146a-5p, and miR-181a-5p and downregulation of miR-130b-3p and miR-195-5p). It was able to identify 80.52% cases at a 10.0% FPR. Highly efficient early identification of later occurrences of stillbirth was achieved via the combination of eleven microRNA biomarkers (upregulation of miR-1-3p, miR-16-5p, miR-17-5p, miR-20a-5p, miR-146a-5p, and miR-181a-5p and downregulation of miR-130b-3p, miR-145-5p, miR-210-3p, miR-342-3p, and miR-574-3p) or, alternatively, by the combination of just two upregulated microRNA biomarkers (miR-1-3p and miR-181a-5p). The predictive power achieved 95.83% cases at a 10.0% FPR and, alternatively, 91.67% cases at a 10.0% FPR. The models based on the combination of selected cardiovascular-disease-associated microRNAs had very high predictive potential for miscarriages or stillbirths and may be implemented in routine first-trimester screening programs.

Fetal-maternal interactions during pregnancy: a 'three-in-one' perspective

A successful human pregnancy requires the maternal immune system to recognize and tolerate the semi-allogeneic fetus, allowing for appropriate trophoblasts invasion and protecting the fetus from invading pathogens. Therefore, maternal immunity is critical for the establishment and maintenance of pregnancy, especially at the maternal-fetal interface. Anatomically, the maternal-fetal interface has both maternally- and fetally- derived cells, including fetal originated trophoblasts and maternal derived immune cells and stromal cells. Besides, a commensal microbiota in the uterus was supposed to aid the unique immunity in pregnancy. The appropriate crosstalk between fetal derived and maternal originated cells and uterine microbiota are critical for normal pregnancy. Dysfunctional maternal-fetal interactions might be associated with the development of pregnancy complications. This review elaborates the latest knowledge on the interactions between trophoblasts and decidual immune cells, highlighting their critical roles in maternal-fetal tolerance and pregnancy development. We also characterize the role of commensal bacteria in promoting pregnancy progression. Furthermore, this review may provide new thought on future basic research and the development of clinical applications for pregnancy complications.

Estrogen-sensitive activation of SGK1 induces M2 macrophages with anti-inflammatory properties and a Th2 response at the maternal-fetal interface

BACKGROUND

Decidual macrophages participate in immune regulation at the maternal-fetal interface. Abnormal M1/M2 polarization of decidual macrophages might predispose immune maladaptation in recurrent pregnancy loss (RPL). However, the mechanism of decidual macrophage polarization is unclear. We explored the role of Estradiol (E₂)-sensitive serum-glucocorticoid regulated kinase (SGK) 1 in promoting macrophage polarization and suppressing inflammation at the maternal-fetal interface.

METHODS

We assessed serum levels of E₂ and progesterone during first trimester of pregnancy in women with or without threatened miscarriages (ended in live birth, n = 448; or early miscarriages, n = 68). For detection of SGK1 in decidual macrophages, we performed immunofluorescence labeling and western blot analysis applying decidual samples from RPL (n = 93) and early normal pregnancy (n = 66). Human monocytic THP-1 cells were differentiated into macrophages and treated with Toll-like receptor (TLR) 4 ligand lipopolysaccharide (LPS), E₂, inhibitors or siRNA for in vitro analysis. Flow cytometry analysis were conducted to detect macrophages polarization. We also applied ovariectomized (OVX) mice with hormones exploring the mechanisms underlying the regulation of SGK1 activation by E₂ in the decidual macrophages in vivo.

RESULTS

SGK1 expression down regulation in the decidual macrophages of RPL was consistent with the lower concentration and slower increment of serum E₂ from 4 to 12 weeks of gestation seen in these compromised pregnancies. LPS reduced SGK1 activities, but induced the pro-inflammatory M1 phenotype of THP-1 monocyte-derived macrophages and T helper (Th) 1 cytokines that favored pregnancy loss. E₂ pretreatment promoted SGK1 activation in the decidual macrophages of OVX mice in vivo. E₂ pretreatment amplified SGK1 activation in TLR4-stimulated THP-1 macrophages in vitro through the estrogen receptor beta (ERβ) and PI3K pathway. E₂-sensitive activation of SGK1 increased M2 macrophages and Th2 immune responses, which were beneficial to successful pregnancy, by inducing ARG1 and IRF4 transcription, which are implicated in normal pregnancy. The experiments on OVX mice have shown that pharmacological inhibition of E₂ promoted nuclear translocation of NF-κB in the decidual macrophages. Further more, pharmacological inhibition or knockdown of SGK1 in TLR4-stimulated THP-1 macrophages activated NF-κB by promoting its nuclear translocation, leading to increased secretion of pro-inflammatory cytokines involved in pregnancy loss.

CONCLUSION

Our findings highlighted the immunomodulatory roles of E₂-activated SGK1 in Th2 immune responses by priming anti-inflammatory M2 macrophages at the maternal-fetal interface, resulting in a balanced immune microenvironment during pregnancy. Our results suggest new perspectives on future preventative strategies for RPL.

MicroRNA-146a-5p induces cell cycle arrest and enhances apoptosis in gastric cancer via targeting CDC14A

Objective: The present study was designed to investigate the expression of miRNA-146a-5p in gastric cancer (GC) tissues and the paired nonmalignant counterparts, to explore the influences of miRNA-146a-5p on the cell biological behavior of MKN-28 cells (highly metastatic human gastric cancer cells), and to identify the function of abnormal expression of its target gene cell division cycle 14 homolog A (CDC14A) in GC. Methods: We detected the expression of miRNA-146a-5p in formalin-fixed and paraffin-embedded (FFPE) GC tissues through microarray and quantitative real-time polymerase chain reaction (qRT-PCR). Then, we employed cell counting kit-8 (CCK-8) assays, cell cycle assays, and apoptosis analysis to uncover the latent function of miRNA-146a-5p in MKN-28 human GC cells. We also validated the target of miRNA-146a-5p via luciferase reporter assays. Results: miRNA-146a-5p levels were examined in the majority of primary GC tissues and several GC cell lines. As a result, miRNA-146a-5p levels were significantly declined in the GC tissues and cells. In addition, miRNA-146a-5p demonstrated a straight act on its 3'-untranslated region (3'-UTR) of CDC14A mRNA, accordingly decreasing the contents of CDC14A mRNA as well as its protein expression. An inverse correlation between CDC14A and miRNA-146a-5p was observed. Conclusion: The data suggest miRNA-146a-5p may contribute to inducing cell cycle arrest as well as prompting GC cell apoptosis via directly targeting CDC14A. Therefore, miRNA-146a-5p may be a potential indicator of the occurrence and development of GC.

Extracellular vesicle-transmitted miR-671-5p alleviates lung inflammation and injury by regulating the AAK1/NF-κB axis

Mesenchymal stem cells regulate remote intercellular signaling communication via their secreted extracellular vesicles. Here, we report that menstrual blood-derived stem cells alleviate acute lung inflammation and injury via their extracellular vesicle-transmitted miR-671-5p. Disruption of this abundantly expressed miR-671-5p dramatically reduced the ameliorative effect of extracellular vesicles released by menstrual blood-derived stem cells on lipopolysaccharide (LPS)-induced pulmonary inflammatory injury. Mechanistically, miR-671-5p directly targets the kinase AAK1 for post-transcriptional degradation. AAK1 is found to positively regulate the activation of nuclear factor κB (NF-κB) signaling by controlling the stability of the inhibitory protein IκBα. This study identifies a potential molecular basis of how extracellular vesicles derived from mesenchymal stem cells improve pulmonary inflammatory injury and highlights the functional importance of the miR-671-5p/AAK1 axis in the progression of pulmonary inflammatory diseases. More importantly, this study provides a promising cell-based approach for the treatment of pulmonary inflammatory disorders through an extracellular vesicle-dependent pathway.

The biological functions of maternal-derived extracellular vesicles during pregnancy and lactation and its impact on offspring health

During pregnancy and lactation, mothers provide not only nutrients, but also many bioactive components for their offspring through placenta and breast milk, which are essential for offspring development. Extracellular vesicles (EVs) are nanovesicles containing a variety of biologically active molecules and participate in the intercellular communication. In the past decade, an increasing number of studies have reported that maternal-derived EVs play a crucial role in offspring growth, development, and immune system establishment. Hereby, we summarized the characteristics of EVs; biological functions of maternal-derived EVs during pregnancy, including implantation, decidualization, placentation, embryo development and birth of offspring; biological function of breast milk-derived EVs (BMEs) on infant oral and intestinal diseases, immune system, neurodevelopment, and metabolism. In summary, emerging studies have revealed that maternal-derived EVs play a pivotal role in offspring health. As such, maternal-derived EVs may be used as promising biomarkers in offspring disease diagnosis and treatment. However, existing research on maternal-derived EVs and offspring health is largely limited to animal and cellular studies. Evidence from human studies is needed.

HSP70 regulates lipid metabolism of decidual macrophages to maintain normal pregnancy

Dysfunction of decidual macrophages (dMs) are closely associated with recurrent pregnancy loss (RPL) which brings great suffering to patients. Metabolism is essential for regulating macrophage function. Identifying molecules that regulate metabolism and function of dMs is important to revealing the pathogenesis of RPL. Single-cell sequencing data of decidual immune cells from control and RPL patients were downloaded from the GSA database and converted into feature-barcode matrices by Cell Ranger. After quality control, removal of double cell and clustering of all cells, 3579 macrophages were extracted for normalisation, scaling and re-clustering. Function and metabolism analyses were performed by R packages AddMoudleScore, scMetabolism and AUCell. Metabolism clustering based on metabolism-related genes to clarify the metabolic characteristics of macrophages clusters. These results indicated that macrophage characterised by lipid metabolism were reduced in RPL and differential expression genes analysis found that HSP70 was significantly decreased in the RPL group. Furthermore, immunofluorescence staining demonstrated that HSP70 was significantly downregulated in dMs of RPL patients compared to controls. In conclusion, HSP70 may maintain normal pregnancy by regulating lipid metabolism of dMs. This study provides new insights into the molecular mechanisms regulating the function of dMs and provides a theoretical basis for the development of new therapies for RPL.

MicroRNA-124 expression in Kupffer cells modulates liver injury by targeting IL-6/STAT3 signaling

MicroRNA-124 (miR-124) is related to liver injury due to chronic hepatitis B (CHB) and hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF). However, the mechanism whereby miR-124 regulates liver inflammation remains unknown. In this study, we show that serum miR-124 serves as a compensatory predictive factor for organ failure and the 28-day prognosis of patients with HBV-ACLF. Moreover, within a mouse model of concanavalin A-induced acute liver injury, miR-124 is highly expressed in Kupffer cells. Overexpression of miR-124 significantly decreases interleukin-6 (IL-6) secretion, and relieves pathological liver necrosis to a great extent. Mechanistically, miR-124 directly targets the 3'-untranslated region of signal transducer and activator of transcription 3 (STAT3) and inhibits IL-6/STAT3 signaling, which reduces pro-inflammatory Kupffer cell polarization. Collectively, our findings suggest that miR-124 can potentially serve as a predictive biomarker for HBV-ACLF prognosis and may represent a promising therapeutic target for relieving severe liver injury resulting from cytokine storms.

The role of extracellular vesicles in intercellular communication in human reproduction

Embryo-maternal cross-talk has emerged as a vitally important process for embryo development and implantation, which is driven by secreted factors and extracellular vesicles (EVs). The EV cargo of bioactive molecules significantly influences target cells and primes them for critical stages of reproductive biology, including embryo development, adhesion, and implantation. Recent research has suggested that EVs and their cargo represent a powerful non-invasive tool that can be leveraged to assess embryo and maternal tissue quality during assisted reproduction treatments. Here, we review the current scientific literature regarding the intercellular cross-talk between embryos and maternal tissues from fertilization to implantation, focusing on human biology and signaling mechanisms identified in animal models.

Extracellular vesicles-encapsulated microRNA in mammalian reproduction: A review

Extracellular vesicles (EVs) are nanoscale cell-derived lipid vesicles that participate in cell-cell communication by delivering cargo, including mRNAs, proteins and non-coding RNAs, to recipient cells. MicroRNA (miRNA), a non-coding RNA typically 22 nucleotides long, is crucial for nearly all developmental and pathophysiological processes in mammals by regulating recipient cells gene expression. Infertility is a worldwide health issue that affects 10-15% of couples during their reproductive years. Although assisted reproductive technology (ART) gives infertility couples hope, the failure of ART is mainly unknown. It is well accepted that EVs-encapsulated miRNAs have a role in different reproductive processes, implying that these EVs-encapsulated miRNAs could optimize ART, improve reproductive rate, and treat infertility. As a result, in this review, we describe the present understanding of EVs-encapsulated miRNAs in reproduction regulation.

Tim-3 Coordinates Macrophage-Trophoblast Crosstalk via Angiogenic Growth Factors to Promote Pregnancy Maintenance

T-cell immunoglobulin mucin-3 (Tim-3) is an important checkpoint that induces maternal-fetal tolerance in pregnancy. Macrophages (Mφs) play essential roles in maintaining maternal-fetal tolerance, remodeling spiral arteries, and regulating trophoblast biological behaviors. In the present study, the formation of the labyrinth zone showed striking defects in pregnant mice treated with Tim-3 neutralizing antibodies. The adoptive transfer of Tim-3⁺Mφs, rather than Tim-3^-Mφs, reversed the murine placental dysplasia resulting from Mφ depletion. With the higher production of angiogenic growth factors (AGFs, including PDGF-AA, TGF-α, and VEGF), Tim-3⁺dMφs were more beneficial in promoting the invasion and tube formation ability of trophoblasts. The blockade of AGFs in Tim-3⁺Mφs led to the narrowing of the labyrinthine layer of the placenta, compromising maternal-fetal tolerance, and increasing the risk of fetal loss. Meanwhile, the AGFs-treated Tim-3^-Mφs could resolve the placental dysplasia and fetal loss resulting from Mφ depletion. These findings emphasized the vital roles of Tim-3 in coordinating Mφs-extravillous trophoblasts interaction via AGFs to promote pregnancy maintenance and in extending the role of checkpoint signaling in placental development. The results obtained in our study also firmly demonstrated that careful consideration of reproductive safety should be taken when selecting immune checkpoint and AGF blockade therapies in real-world clinical care.

Messenger roles of extracellular vesicles during fertilization of gametes, development and implantation: Recent advances

Extracellular vesicles (EVs) have become a research hotspot in recent years because they act as messengers between cells in the physiological and pathological processes of the human body. It can be produced by the follicle, prostate, embryo, uterus, and oviduct in the reproductive field and exists in the extracellular environment as follicular fluid, semen, uterine cavity fluid, and oviduct fluid. Because extracellular vesicles are more stable at transmitting information, it allows all cells involved in the physiological processes of embryo formation, development, and implantation to communicate with one another. Extracellular vesicles carried miRNAs and proteins as mail, and when the messenger delivers the mail to the recipient cell, the recipient cell undergoes a series of changes. Current research begins with intercepting and decoding the information carried by extracellular vesicles. This information may help us gain a better understanding of the secrets of reproduction, as well as assist reproductive technology as an emerging marker and treatment.

Deletion of Insulin-like growth factor II mRNA-binding protein 3 participates in the pathogenesis of recurrent spontaneous abortion by inhibiting IL-10 secretion and inducing M1 polarization

Insulin-like growth factor II mRNA-binding protein 3 (IGF2BP3) has been proved to affect trophoblast function and embryonic development, but its role and potential mechanism in recurrent spontaneous abortion (RSA) are not clear. RSA is a complex reproductive disease, causing physical and mental damage to patients. In recent years, many studies have found that immune microenvironment is vital to maintain successful pregnancy in the maternal fetal interface. Therefore, this study aims to explore the role of IGF2BP3 in affecting macrophage polarization and its possible mechanism. In this article, we found that IGF2BP3 expression was decreased in placental villous samples of human and RSA mouse model, and knockdown of IGF2BP3 in HTR8/SVneo cells promotes M1 Mφ polarization. Combining with RNA sequencing analysis, we found that IGF2BP3 may regulate the Mφ polarization by affecting the expression of trophoblast cytokines, especially IL-10 secretion. Further mechanistic studies showed that knockdown of IGF2BP3 decreased expression of IL-10 by activating NF-κB pathway. Moreover, we found that M2 Mφ promote trophoblast invasion not IGF2BP3 dependent. Our study reveals the interaction between trophoblast cells and macrophages at the maternal-fetal interface of RSA patients, and will provide theoretical guidance for its diagnosis and treatment of RSA patients.

Current Status of Research on Small Extracellular Vesicles for the Diagnosis and Treatment of Urological Tumors

Extracellular vesicles (EVs) are important mediators of communication between tumor cells and normal cells. These vesicles are rich in a variety of contents such as RNA, DNA, and proteins, and can be involved in angiogenesis, epithelial-mesenchymal transition, the formation of pre-metastatic ecological niches, and the regulation of the tumor microenvironment. Small extracellular vesicles (sEVs) are a type of EVs. Currently, the main treatments for urological tumors are surgery, radiotherapy, and targeted therapy. However, urological tumors are difficult to diagnose and treat due to their high metastatic rate, tendency to develop drug resistance, and the low sensitivity of liquid biopsies. Numerous studies have shown that sEVs offer novel therapeutic options for tumor treatment, such as tumor vaccines and tumor drug carriers. sEVs have attracted a great deal of attention owing to their contribution to in intercellular communication, and as novel biomarkers, and role in the treatment of urological tumors. This article reviews the research and applications of sEVs in the diagnosis and treatment of urological tumors.

Endometrial small extracellular vesicles regulate human trophectodermal cell invasion by reprogramming the phosphoproteome landscape

A series of cyclical events within the uterus are crucial for pregnancy establishment. These include endometrial regeneration following menses, under the influence of estrogen (proliferative phase), then endometrial differentiation driven by estrogen/progesterone (secretory phase), to provide a microenvironment enabling attachment of embryo (as a hatched blastocyst) to the endometrial epithelium. This is followed by invasion of trophectodermal cells (the outer layer of the blastocyst) into the endometrium tissue to facilitate intrauterine development. Small extracellular vesicles (sEVs) released by endometrial epithelial cells during the secretory phase have been shown to facilitate trophoblast invasion; however, the molecular mechanisms that underline this process remain poorly understood. Here, we show that density gradient purified sEVs (1.06-1.11 g/ml, Alix⁺ and TSG101⁺, ∼180 nm) from human endometrial epithelial cells (hormonally primed with estrogen and progesterone vs. estrogen alone) are readily internalized by a human trophectodermal stem cell line and promote their invasion into Matrigel matrix. Mass spectrometry-based proteome analysis revealed that sEVs reprogrammed trophectoderm cell proteome and their cell surface proteome (surfaceome) to support this invasive phenotype through upregulation of pro-invasive regulators associated with focal adhesions (NRP1, PTPRK, ROCK2, TEK), embryo implantation (FBLN1, NIBAN2, BSG), and kinase receptors (EPHB4/B2, ERBB2, STRAP). Kinase substrate prediction highlighted a central role of MAPK3 as an upstream kinase regulating target cell proteome reprogramming. Phosphoproteome analysis pinpointed upregulation of MAPK3 T204/T202 phosphosites in hTSCs following sEV delivery, and that their pharmacological inhibition significantly abrogated invasion. This study provides novel molecular insights into endometrial sEVs orchestrating trophoblast invasion, highlighting the microenvironmental regulation of hTSCs during embryo implantation.

Correlation and predictive value of serum miR-146b-5p expression during the first trimester of pregnancy with pre-eclampsia

The aim of this study was to investigate the correlation and predictive value of serum miR-146b-5p expression during the first trimester of pregnancy with pre-eclampsia (PE). In total, 32 normal pregnant women (the control group) and 58 subjects with PE were randomly selected from eligible case data. The serum levels of miR-146b-5p, pregnancy associated plasma protein A (PAPP-A) and free beta subunit of human chorionic gonadotropin (free β-hCG) were then detected. Next, we established predictive models of single or multiple markers for PE. The levels of miR-146b-5p in the mild pre-eclampsia (mPE) and severe pre-eclampsia (sPE) groups were higher than the control group and there were significant differences between the three groups (F = 3.424, P = 0.037). The statistical results of the model before and after 200 times 10-fold cross-validation were as follows: miR-146b-5p (AUC = 0.723 vs AUC = 0.710); miR-146b-5p + BMI + MAP + free β-hCG MoM + PAPP-A MoM (AUC = 0.929 vs AUC = 0.851). We found that expression levels of miR-146b-5p in the first trimester were significantly higher in the serum of pregnant women with PE than in the normal pregnancy group. A prediction model in combination with miR-146b-5p and other markers improved the early predictive value for PE.IMPACT STATEMENTWhat is already known on this subject? Pre-eclampsia is a complex systemic disease with hypertension as the main clinical manifestation and causes extensive damage to the body. Some existing maternal biochemical markers have limited value in predicting PE, and new biomarkers with high sensitivity and specificity are urgently needed in clinical practice. There are a variety of abnormal expression miRNAs in PE, however, the relationship between miR-146b-5p and PE has yet to be fully elucidated.What do the results of this study add? We first found that expression levels of serum miR-146b-5p in the first trimester were significantly higher in PE than in a normal pregnancy group. A prediction model a combination of miR-146b-5p and other maternal characteristics and biochemical markers can improve the early predictive value for PE.What are the implications of these findings for clinical practice and/or further research? PE progresses rapidly and has become a severe target organ complication when discovered. Therefore, the early prediction of a high risk of PE, along with early intervention and prevention measures, are of great significance. Compared to maternal biochemical markers, combination of miR-146b-5p and maternal characteristics and biochemical markers can improve the early predictive value for PE.

Decidual macrophages in recurrent spontaneous abortion

Recurrent spontaneous abortion (RSA) is defined as two or more pregnancy loss, affecting the happiness index of fertility couples. The mechanisms involved in the occurrence of RSA are not clear to date. The primary problem for the maternal immune system is how to establish and maintain the immune tolerance to the semi-allogeneic fetuses. During the pregnancy, decidual macrophages mainly play an important role in the immunologic dialogue. The purpose of this study is to explore decidual macrophages, and to understand whether there is a connection between these cells and RSA by analyzing their phenotypes and functions. Pubmed, Web of Science and Embase were searched. The eligibility criterion for this review was evaluating the literature about the pregnancy and macrophages. Any disagreement between the authors was resolved upon discussion and if required by the judgment of the corresponding author. We summarized the latest views on the phenotype, function and dysfunction of decidual macrophages to illuminate its relationship with RSA.