Exploring the clinical and cellular mechanisms of LncRNA-KCNQ1OT1/miR-29a-3p/SOCS3 molecular axis in cases of unexplained recurrent spontaneous abortion.

OBJECTIVE: The objective of this study is to explore the functions and mechanisms of the LncRNA-KCNQ1OT1/miR-29a-3p/SOCS3 molecular pathway in the context of unexplained recurrent spontaneous abortion (URSA). METHODS: We conducted qRT-PCR to assess the levels of LncRNA-KCNQ1OT1, miR-29a-3p, and SOCS3 in both abortion tissues from women who experienced URSA and healthy early pregnant women. A dual-luciferase assay was employed to investigate whether miR-29a-3p targets SOCS3. Furthermore, RNA IP and RNA Pull-Down assays were employed to confirm the interaction between KCNQ1OT1 and SOCS3 with miR-29a-3p. RNA FISH was used to determine the cellular localization of KCNQ1OT1. Additionally, trophoblast cells (HTR8/SVneo) were cultured and the CCK-8 assay was utilized to assess cell proliferation, while flow cytometry was employed to analyze cell apoptosis. RESULTS: Compared to abortion tissues obtained from healthy early pregnant individuals, those from women who experienced URSA displayed a notable downregulation of KCNQ1OT1 and SOCS3, accompanied by an upregulation of miR-29a-3p. Suppression of KCNQ1OT1 resulted in the inhibition of cell proliferation and the facilitation of apoptosis in HTR8/SVneo cells. Our findings suggest that KCNQ1OT1 may exert a regulatory influence on SOCS3 through a competitive binding mechanism with miR-29a-3p. Notably, KCNQ1OT1 exhibited expression in both the cytoplasm and nucleus, with a predominant localization in the cytoplasm. Furthermore, we observed a negative regulatory relationship between miR-29a-3p and SOCS3, as the miR-29a-3p mimic group demonstrated significantly reduced cell proliferation and an increased rate of apoptosis when compared to the negative control (NC mimic) group. Additionally, the SOCS3 Vector group exhibited a substantial improvement in proliferation capability and a marked reduction in the apoptosis rate in comparison to the NC Vector group. The miR-29a-3p mimic + SOCS3 Vector group demonstrated a remarkable enhancement in proliferation and a reduction in apoptosis when compared to the miR-29a-3p mimic group. CONCLUSION: The competitive binding of miR-29a-3p to LncRNA-KCNQ1OT1 appears to result in the elevation of SOCS3 expression, consequently fostering the proliferation of trophoblast cells while concomitantly suppressing apoptosis.

ENO1 promotes trophoblast invasion regulated by E2F8 in recurrent miscarriage.

Recurrent miscarriage (RM) is related to the dysfunction of extravillous trophoblast cells (EVTs), but the comprehensive mechanisms remain largely unexplored. We analyzed single-cell RNA sequencing (scRNA-seq), bulk RNA sequencing and microarray datasets obtained from Gene Expression Omnibus (GEO) database to explore the hub genes in the mechanisms of RM. We identified 1724 differentially expressed genes (DEGs) in EVTs from the RM, and they were all expressed along the trajectory of EVTs. These DEGs were associated with hypoxia and glucose metabolism. Single-cell Regulatory Network Inference and Clustering (SCENIC) analysis revealed that E2F transcription factor (E2F) 8 (E2F8) was a key transcription factor for these DEGs. And the expression of ENO1 can be positively regulated by E2F8 via RNA sequencing analysis. Subsequently, we performed immunofluorescence assay (IF), plasmid transfection, western blotting, chromatin immunoprecipitation (ChIP), real-time quantitative polymerase chain reaction (qRT-PCR), and transwell assays for validation experiments. We found that the expression of alpha-Enolase 1 (ENO1) was lower in the placentas of RM. Importantly, E2F8 can transcriptionally regulate the expression of ENO1 to promote the invasion of trophoblast cells by inhibiting secreted frizzled-related protein 1/4 (SFRP1/4) to activate Wnt signaling pathway. Our results suggest that ENO1 can promote trophoblast invasion via an E2F8-dependent manner, highlighting a potential novel target for the physiological mechanisms of RM.

BMP4 in Human Endometrial Stromal Cells Can Affect Decidualization by Regulating FOXO1 Expression.

CONTEXT: Recurrent spontaneous abortion (RSA) is defined as the loss of 2 or more consecutive intrauterine pregnancies with the same sexual partner in the first trimester. Despite its significance, the etiology and underlying mechanisms of RSA remain elusive. Defective decidualization is proposed as one of the potential causes of RSA, with abnormal decidualization leading to disturbances in trophoblast invasion function. OBJECTIVE: To assess the role of bone morphogenetic protein 4 (BMP4) in decidualization and RSA. METHODS: Decidual samples were collected from both RSA patients and healthy controls to assess BMP4 expression. In vitro cell experiments utilized the hESC cell line to investigate the impact of BMP4 on decidualization and associated aging, as well as its role in the maternal-fetal interface communication. Subsequently, a spontaneous abortion mouse model was established to evaluate embryo resorption rates and BMP4 expression levels. RESULTS: Our study identified a significant downregulation of BMP4 expression in the decidua of RSA patients compared to the normal control group. In vitro, BMP4 knockdown resulted in inadequate decidualization and inhibited associated aging processes. Mechanistically, BMP4 was implicated in the regulation of FOXO1 expression, thereby influencing decidualization and aging. Furthermore, loss of BMP4 hindered trophoblast migration and invasion via FOXO1 modulation. Additionally, BMP4 downregulation was observed in RSA mice. CONCLUSION: Our findings highlighted the downregulation of BMP4 in both RSA patients and mice. BMP4 in human endometrial stromal cells was shown to modulate decidualization by regulating FOXO1 expression. Loss of BMP4 may contribute to the pathogenesis of RSA, suggesting potential avenues for abortion prevention strategies.

Association of estrogen receptor and progesterone receptor genetic polymorphisms with recurrent pregnancy loss: A systematic review and meta-analysis.

OBJECTIVE: Estrogen and progesterone play key roles in the maintenance of pregnancy, and their function is mediated via estrogen receptor 1 (ESR1)/estrogen receptor 2 (ESR2) and progesterone receptor (PGR), respectively. It has been suggested the genetic variations in ESR1, ESR2, and PGR may contribute to recurrent pregnancy loss (RPL); however, the available evidence remains controversial. This meta-analysis aimed to explore the relation of various polymorphisms in ESR1, ESR2, and PGR genes to the risk of RPL. METHODS: A systematic literature search was conducted using PubMed and Scopus up to August 2023 to obtain relevant studies. The odds ratios (ORs) with 95% confidence intervals (95% CIs) were computed and pooled with the use of random-effects models to test the associations. RESULTS: A total of 31 studies with 12 different polymorphisms, including 5 polymorphisms for ESR1, 3 polymorphisms for ESR2, and 4 polymorphisms for PGR, were analyzed in this meta-analysis. Overall, no significant relationship was found between various polymorphisms of ESR1 and ESR2 with RPL in any of the genetic analysis models. PGR rs590688 (C > G) polymorphism was significantly related to the elevated risk of RPL under the dominant (OR = 1.67; 95 %CI: 1.15-2.44), allelic (OR = 1.55; 95 %CI: 1.13-2.12), and GC vs. CC (OR = 1.55; 95 %CI: 1.07-2.23) models. No significant association was identified for other variants of PGR gene. CONCLUSION: Unlike estrogen receptors, variations in PGR rs590688 (C > G) may be linked to the increased risk of RPL. More studies are required to confirm this finding.

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.

Multi-omics reveals the switch role of abnormal methylation in the regulation of decidual macrophages function in recurrent spontaneous abortion.

RSA, recurrent spontaneous abortion, often causes serious physical damage and psychological pressure in reproductive women with unclarified pathogenesis. Abnormal function of decidual cells and aberrant DNA methylation have been reported to cause RSA, but their association remains unclear. Here, we integrated transcriptome, DNA methylome, and scRNA-seq to clarify the regulatory relationship between DNA methylation and decidual cells in RSA. We found that DNA methylation mainly influenced the function of decidual macrophages (DMs), of which four hub genes, HLA-A, HLA-F, SQSTM1/P62, and Interferon regulatory factor 7 (IRF7), related to 22 hypomethylated CpG sites, regulated 16 hub pathways to participate in RSA pathogenesis. In particular, using transcription factor analysis, it is suggested that the upregulation of IRF7 transcription was associated with enhanced recruitment of the transcription factor STAT1 by the hypomethylated promoter region of IRF7. As the current research on DNA methylation of macrophages in the uterine microenvironment of RSA is still blank, our systematic picture of abnormal DNA methylation in regulating DM function provides new insights into the role of DNA methylation in RSA occurrence, which may aid in further prevention and treatment of RSA.

MANF Promotes Unexplained Recurrent Miscarriages by Interacting with NPM1 and Downregulating Trophoblast Cell Migration and Invasion.

Dysplasia and invasive defects in early trophoblasts contribute to unexplained recurrent miscarriages (URMs). Mesencephalic astrocyte-derived neurotrophic factor (MANF) inhibits migration and invasion in some cancer cells, but its role in pregnancy-related diseases remains unresolved. Here, we found that MANF levels in the peripheral blood and aborted tissue of URM women were higher than in normal controls, irrespective of pregnancy or miscarriage. We confirm the interaction between MANF and nucleophosmin 1 (NPM1) in trophoblasts of URM patients, which increases the ubiquitination degradation of NPM1, leading to upregulation of the p53 signaling pathway and inhibition of cell proliferation, migration, and invasion ability. Using a URM mouse model, we found that MANF downregulation resulted in reduced fetal resorption; however, concomitant NPM1 downregulation led to increased abortion rates. These data indicate that MANF triggers miscarriage via NPM1 downregulation and p53 activation. Thus, MANF downregulation or disruption of the MANF-NPM1 interaction could be targets for URM therapeutics.

GRIM-19 deficiency promotes macrophage polarization to the M1 phenotype partly through glycolysis in unexplained recurrent spontaneous abortion†.

The occurrence of unexplained recurrent spontaneous abortion (URSA) is closely related to immune system disorders, however, the underlying mechanisms remain unclear. The purpose of this study was to investigate the expression of GRIM-19 in URSA and the possible pathogenesis of URSA according to macrophage polarization. Here, we showed that GRIM-19 was downregulated in the uterine decidual macrophages of patients with URSA and that GRIM-19 downregulation was accompanied by increased M1 macrophage polarization. Furthermore, the expression levels of glycolytic enzymes were substantially enhanced in the uterine decidual macrophages of URSA patients, and glycolysis in THP-1-derived macrophages was further enhanced by the downregulation of GRIM-19. Additionally, the increase of M1 macrophages resulting from the loss of GRIM-19 was significantly reversed in cells treated with 2-deoxy-D-glucose (2-DG, an inhibitor of glycolysis). To provide more direct evidence, GRIM-19 deficiency was shown to promote macrophage polarization to the M1 phenotype in GRIM-19+/- mouse uteri. Overall, our study provides evidence that GRIM-19 deficiency may play a role in regulating macrophage polarization in URSA, and that glycolysis may participate in this process.

Progesterone-mediated immunoregulation of cytokine signaling by miRNA-133a and 101-3p in Chlamydia trachomatis-associated recurrent spontaneous abortion.

miRNAs regulate the expression of various genes involved in cellular and metabolic pathways in pregnancy related complications including recurrent spontaneous abortion (RSA). Modulation of progesterone and associated pro-inflammatory cytokines by miRNAs in Chlamydia trachomatis-associated RSA is still under investigation. Present study aimed to evaluate the expression/correlation of serum-circulating miRNAs-133a, 101-3p, 320b, 146b-5p, 24, 559, progesterone and few cytokines in C. trachomatis-positive spontaneous aborters. Non-heparinized blood and urine was collected from 120 patients with history of RSA (Group I) and 120 patients with ≥ 2 successful deliveries (Group II) attending Department of Obstetrics and Gynecology, Safdarjung hospital, New Delhi, India. C. trachomatis detection was performed by PCR and chlamydial load by real time PCR. Progesterone concentration was estimated by ELISA. miRNAs and cytokine expression was studied by quantitative real-time PCR and correlated with progesterone expression. Twenty six patients were found to be positive for C. trachomatis. miRNAs- 133a, 101-3p showed maximum upregulation in infected versus control patients. miRNA expression showed positive correlation with chlamydial load. Progesterone concentration showed significant decrease while cytokines (IL-6, IFN-γ, TNF-α) were significantly upregulated in C. trachomatis-positive patients. Positive correlation was observed between expression of miRNAs-133a and 101-3p and cytokines while negative correlation was observed with progesterone in infected RSA patients. Correlation between progesterone and cytokines was found to be significantly negative in infected RSA patients. Although further validation is required, the study concludes that miR-133a and 101-3p are of clinical importance and have a role in immunoregulation of progesterone and cytokines in infection associated RSA.

Analysis of copy number variations and possible candidate genes in spontaneous abortion by copy number variation sequencing.

Introduction: Embryonic chromosomal abnormalities represent a major causative factor in early pregnancy loss, highlighting the importance of understanding their role in spontaneous abortion. This study investigates the potential correlation between chromosomal abnormalities and spontaneous abortion using copy number variation sequencing (CNV-seq), a Next-Generation Sequencing (NGS) technology. Methods: We analyzed Copy Number Variations (CNVs) in 395 aborted fetal specimens from spontaneous abortion patients by CNV-seq. And collected correlated data, including maternal age, gestational week, and Body Mass Index (BMI), and analyzed their relationship with the CNVs. Results: Out of the 395 cases, 67.09% of the fetuses had chromosomal abnormalities, including numerical abnormalities, structural abnormalities, and mosaicisms. Maternal age was found to be an important risk factor for fetal chromosomal abnormalities, with the proportion of autosomal trisomy in abnormal karyotypes increasing with maternal age, while polyploidy decreased. The proportion of abnormal karyotypes with mosaic decreased as gestational age increased, while the frequency of polyploidy and sex chromosome monosomy increased. Gene enrichment analysis identified potential miscarriage candidate genes and functions, as well as pathogenic genes and pathways associated with unexplained miscarriage among women aged below or over 35 years old. Based on our study, it can be inferred that there is an association between BMI values and the risk of recurrent miscarriage caused by chromosomal abnormalities. Discussion: Overall, these findings provide important insights into the understanding of spontaneous abortion and have implications for the development of personalized interventions for patients with abnormal karyotypes.

HNRNPC mediated m6A methylation of 5-methyltetrahydrofolate-homocysteine methyltransferase and involved in the occurrence of RSA.

N6-methyladenosine methylated modification has been shown to play roles in recurrent spontaneous abortion. We aimed to explore role of heterogeneous nuclear ribonucleoprotein C in the occurrence of recurrent spontaneous abortion. We collected embryonic villous tissues from 3 patients with recurrent spontaneous abortion (RSA group) and 3 normal control pregnancy patients. Methylated RNA immunoprecipitation sequencing, RNA sequencing, methylated RNA immunoprecipitation quantitative PCR were conducted to detect the differentially expressed m6A methylation modification gene and regulatory gene in patients with recurrent spontaneous abortion. Methylated RNA immunoprecipitation sequencing and RNA sequencing results showed that the mRNA expression level of heterogeneous nuclear ribonucleoprotein C significantly decreased in RSA group and mRNA expression level of 5-methyltetrahydrofolate-homocysteine methyltransferase increased. Real-time quantitative PCR confirmed the differential expression of heterogeneous nuclear ribonucleoprotein C and 5-methyltetrahydrofolate-homocysteine methyltransferase. Methylated RNA immunoprecipitation quantitative PCR result showed that mRNA m6A modification level of 5-methyltetrahydrofolate-homocysteine methyltransferase decreased in RSA group. The results of western blotting, real-time quantitative PCR, immunofluorescence, matrigel invasion and wound healing assays indicated that heterogeneous nuclear ribonucleoprotein C might regulate the expression of 5-methyltetrahydrofolate-homocysteine methyltransferase by mediating m6A modification, thereby reducing the proliferation and migration of trophoblast cell line, ultimately leading to the occurrence of recurrent spontaneous abortion.

Correlation of TGF-ß signaling pathway gene polymorphisms with unexplained recurrent spontaneous abortion.

BACKGROUND: The association of key genes in the transforming growth factor-ß (TGF-ß) signaling pathway and their gene polymorphisms with unexplained recurrent spontaneous abortion (URSA) is unclear. OBJECTIVE: To investigate the association of gene polymorphisms related to the TGF-ß signaling pathway in URSA women. METHODS: The study population consisted of 80 women with URSA and 90 normal control women, of which 10 women with URSA and 10 normal control women underwent high-throughput sequencing to select loci, and the remaining 70 women with URSA and 80 normal control women underwent flight mass spectrometry experiments to verify gene loci polymorphism. A total of 7 polymorphic loci in interleukin-6 (IL-6), TGF-ß1, TNF-α, SMAD1, and TNFRSF4 genes were screened by high-throughput sequencing combined with a review of databases. An SNP flight mass spectrometer (Mass ARRAY detection system) was applied to detect the polymorphisms and their frequencies in 70 women with URSA and 80 normal control women at the 7 gene loci. RESULTS: Among the 7 loci of IL-6, TGF-ß1, TNF-α, SMAD1, and TNFRSF4 genes, 2 loci were found to have significantly different allele and genotype frequency distributions between the 70 URSA and 80 normal controls, one was the IL-6 gene -174G/C locus (rs1800795), the risk of disease was 2.636 and 3.231 times higher in individuals carrying the C allele and CC genotype than in those carrying the G allele and GG genotype, respectively; the other was the TGF-ß1 gene -509T/C locus (rs1800469), and the risk of disease was 1.959 and 3.609 times higher in individuals carrying the T allele and TT genotype than in those carrying the C allele and CC genotype, respectively. The remaining 5 genetic loci have no statistically significant. CONCLUSION: IL-6 gene -174G/C locus (rs1800795) genotype CC and allele C may be the causative factor of URSA, TGF-ß1 gene -509T/C locus (rs1800469) genotype TT and allele T may be the causative factor of URSA, and polymorphisms of the 2 loci may be associated with URSA.

FKBP5 regulates trophoblast-macrophage crosstalk in recurrent spontaneous abortion through PI3K/AKT and NF-κB signaling pathways.

FK506-binding protein 5 (FKBP5) contributes to many diseases; However, it remains unclear whether FKBP5 is relevant to recurrent spontaneous abortion (RSA) and the mechanisms by which it is involved in maternal-fetal immunological tolerance. Placental tissue was collected in women with normal pregnancy and RSA and examined for FKBP5 expression. Human trophoblast cell lines and THP-1-derived M0 macrophages were used to explore the role of FKBP5 in RSA and its mechanism. The role of FKBP5 on pregnancy outcomes was assessed using a mouse model of miscarriage. This study found that upregulation of FKBP5 at the placental interface is involved in the pathogenesis of RSA by depressing trophoblast function and promoting M1-type macrophage polarization. First, FKBP5 expression was upregulated in the villi of RSA, and FKBP5 regulated trophoblast function by inhibiting HAPLN1 expression through suppression of PI3K/AKT signaling. In addition, FKBP5 inhibited trophoblast IL-6 secretion by suppressing PI3K/AKT signaling, thereby promoting macrophage polarization toward the M1 phenotype. Meanwhile, FKBP5 was significantly elevated in decidual macrophages from patients with RSA and promoted M1 macrophage polarization via ROS/NF-κB signaling and further inhibited trophoblast function. Finally, FKBP5 inhibitors improved embryo resorption rate in miscarried mice. In conclusion, FKBP5 is essential in maintaining pregnancy and trophoblast-macrophage crosstalk in the maternal-fetal interface, which may be a potential target for diagnosing and treating RSA.

Identification and verification of diagnostic biomarkers in recurrent pregnancy loss via machine learning algorithm and WGCNA.

Background: Recurrent pregnancy loss defined as the occurrence of two or more pregnancy losses before 20-24 weeks of gestation, is a prevalent and significant pathological condition that impacts human reproductive health. However, the underlying mechanism of RPL remains unclear. This study aimed to investigate the biomarkers and molecular mechanisms associated with RPL and explore novel treatment strategies for clinical applications. Methods: The GEO database was utilized to retrieve the RPL gene expression profile GSE165004. This profile underwent differential expression analysis, WGCNA, functional enrichment, and subsequent analysis of RPL gene expression using LASSO regression, SVM-RFE, and RandomForest algorithms for hub gene screening. ANN model were constructed to assess the performance of hub genes in the dataset. The expression of hub genes in both the RPL and control group samples was validated using RT-qPCR. The immune cell infiltration level of RPL was assessed using CIBERSORT. Additionally, pan-cancer analysis was conducted using Sangerbox, and small-molecule drug screening was performed using CMap. Results: A total of 352 DEGs were identified, including 198 up-regulated genes and 154 down-regulated genes. Enrichment analysis indicated that the DEGs were primarily associated with Fc gamma R-mediated phagocytosis, the Fc epsilon RI signaling pathway, and various metabolism-related pathways. The turquoise module, which showed the highest relevance to clinical symptoms based on WGCNA results, contained 104 DEGs. Three hub genes, WBP11, ACTR2, and NCSTN, were identified using machine learning algorithms. ROC curves demonstrated a strong diagnostic value when the three hub genes were combined. RT-qPCR confirmed the low expression of WBP11 and ACTR2 in RPL, whereas NCSTN exhibited high expression. The immune cell infiltration analysis results indicated an imbalance of macrophages in RPL. Meanwhile, these three hub genes exhibited aberrant expression in multiple malignancies and were associated with a poor prognosis. Furthermore, we identified several small-molecule drugs. Conclusion: This study identifies and validates hub genes in RPL, which may lead to significant advancements in understanding the molecular mechanisms and treatment strategies for this condition.

Proteomic profiling analysis of human endometrium in women with unexplained recurrent spontaneous abortion.

Unexplained recurrent spontaneous abortion (URSA) seriously affects female reproductive health, causing a great burden to patients both physically and mentally. Endometrial decidualization plays an important role in pregnancy, and impaired decidualization is an essential cause of URSA, but the cause of the damage is still poorly understood. This study aimed to reveal the pathogenesis of URSA by analyzing the differential protein expression profiles in the decidual tissue of patients with recurrent abortion compared to those with normal pregnancy. Morphological analysis revealed abnormal decidualization of endometrial tissue in patients with URSA. Quantitative proteomics analysis showed that a total of 146 differentially expressed proteins were identified between the two groups, among which 95 proteins were downregulated and 51 proteins were upregulated. Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways revealed that the protein expression profile and signaling pathways of endometrium in patients with URSA changed significantly, and cytoskeleton remodeling and morphological transformation disorders were associated with abortion induced by incomplete decidualization. Meanwhile, transcription factors analysis showed that the 3 most affected families were zf-C2H2, MYB and HMG. Therefore, our study may provide a basis for searching for potential markers of decidualization injury. SIGNIFICANCE: At present, there are still about 50% of RSA patients with unknown causes, which brings great difficulties and blindness to clinical diagnosis and treatment.The limited proteomic studies on URSA further contribute to the lack of understanding in this field. However, in this study, the focus was on proteomic profiling analysis of the human endometrium in URSA patients compared to normal women. The findings revealed that cytoskeletal remodeling disorder is a significant contributor to the failure of decidualization in URSA patients. This insight highlights the potential role of cytoskeleton-related proteins in the pathogenesis of URSA, providing valuable information for further research and potential therapeutic interventions.

Recognition of the Subtypes Classification and Diagnostic Signature Based on RNA N6-Methyladenosine Regulators in Recurrent Spontaneous Abortion.

Recurrent spontaneous abortion (RSA) is a common reproductive disease in female patients that seriously affects the quality of life of patients. N6-methyladenosine (m6A), as the most common modification, plays an important role in various biological behaviors; however, the relationship between m6A and RSA is still unknown. In the present study, we utilized RNA sequencing data and clinical information of RSA patients and normal women in the GEO database to identify the expression profiles of m6A regulators in RSA. Based on the m6A regulators' expression profiles, we constructed a random forest model consisting of 4 genes to predict the prevalence of RSA patients, including FMR1, METTL14, LRPPRC, and RBMX. The predictive performance of the nomogram was constructed and validated. Not only that, consensus clustering was performed to divide RSA patients into 3 clusters based on the expression of m6A regulators and calculated the m6A scores and immune infiltration of patients in different clusters. It was found that the TH1-type immune response was dominant in the A cluster, the B-type immune activity was poor, and the C cluster was the strongest. In addition, on the basis of m6A typing, we further used the differentially expressed genes between clusters to perform consensus clustering verification, and the results were consistent with the previous findings. In conclusion, the m6A regulators played an indispensable role in the occurrence of RSA, and the m6A-based typing could effectively identify the immune characteristics of different RSA patients to a certain extent, providing a new direction and strategy for the diagnosis and treatment of RSA patients.

Role of the HLA-G regulatory region polymorphisms in idiopathic recurrent spontaneous abortions (RSA).

PROBLEM: HLA-G polymorphisms have a functional impact on its expression and may cause a breakdown of maternal tolerance towards the semi-allogenic fetus, resulting in recurrent spontaneous abortions (RSA). This study reports on the association of HLA-G regulatory region polymorphisms with idiopathic RSA. METHODS: Seventy-five couples with ≥2 spontaneous abortions were recruited in comparison to 75 healthy couples who had normal pregnancies. About 5 mL of blood samples were collected from all the participants, and DNA was extracted. Screening of HLA-G 5'-upstream regulatory region (5'-URR) was done by direct sequencing in 50 each of RSA and healthy couples, respectively. The 14 bp deletion/insertion polymorphism in the 3'-untranslated region (3'-UTR) was genotyped in 75 each of RSA and healthy couples, respectively, by PCR amplification of HLA-G exon 8. MedCalc, GraphPad Prism, Haploview, PLINK, and multifactor dimensionality reduction were used to analyze the data. RESULTS: HLA-G screening revealed the presence of -762C/T, -725C/G, -716T/G, -689A/G, -486C/A, and -477C/G single nucleotide polymorphisms (SNPs) in the 5'-URR. At positions -762 and -477, the frequency of CC homozygotes was significantly higher in controls compared to the patients. The 14 bp deletion/insertion polymorphism in the 3'-UTR showed an association with RSA with the heterozygous genotype being significantly higher in RSA compared to controls. CONCLUSIONS: The study indicates a protective role of the CC genotypes of the two HLA-G 5'-URR polymorphisms, -762C/T and -477C/G, against RSA. It also suggests that women with the 14 bp deletion/insertion genotype have a significantly higher risk of RSA.

Aberrations in the progesterone pathway and the Th1/Th2 cytokine dichotomy - An evaluation of RPL predisposition in the northeast Indian population.

PROBLEM: Recurrent pregnancy loss (RPL) is the spontaneous loss of two or more consecutive pregnancies prior to 20 weeks of gestation, occurring in 1% of the reproductive-age population. It is a major cause of infertility in India with a staggering 7.46% prevalence rate. METHOD OF STUDY: Blood and product of conception (POCs) from RPL cases (n = 65) were enrolled for this study, along with cases of medically terminated pregnancy (MTP, n = 80) and term delivery cases (n = 90) as control. ELISA for progesterone and progesterone induced blocking factor (PIBF) levels was carried out, followed by mRNA expression analysis of progesterone receptor isoform B (PR-B) and its downstream immunomodulatory effectors, namely, PIBF, IL-10 and IL-12. Screening of PROGINS haplotype of PR gene and PIBF polymorphism were also conducted to correlate with their respective gene expression profiles. RESULTS: Serum progesterone level was found to be comparable in the RPL and MTP cases. Although the mRNA expression of PR-B was found to be downregulated in the RPL cases, no significant PROGINS haplotype was observed. Presence of a single nucleotide polymorphism (SNP) in the PIBF gene (rs1372000) was more in healthy controls compared to RPL cases. Serum PIBF levels were found to be lower in the RPL cases with a resultant increase in IL-12 and a decrease in IL-10 mRNA expression in these cases. CONCLUSIONS: This study indicates that progesterone, acting through PIBF, modulates the immunological state of pregnancy to be Th1-biased in RPL, indicative of a pro-inflammatory, labour-like state not desired for a healthy pregnancy.

Spontaneous abortion in the first trimester of pregnancy.

Spontaneous abortions in the first trimester of gravidity represent a clinically significant problem that can affect up to 15% of recognized pregnancies. The causes of early pregnancy loss are very heterogeneous and include genetic, environmental and immunological factors. Although the pathologist's main task is to exclude molar pregnancy, in some cases conventional histological examination can also contribute to the elucidation of the cause of miscarriage and the management of subsequent pregnancies, especially in the case of lesions with a high risk of recurrence that may lead to habitual abortion.

Effects of NGS-based PGT-a for idiopathic recurrent pregnancy loss and implantation failure: a retrospective cohort study.

To clarify the effect of next-generation sequencing (NGS)-based preimplantation genetic testing for aneuploidy (PGT-A) combined with trophectoderm (TE) biopsy on the pregnancy outcomes of idiopathic recurrent pregnancy loss (iRPL) and idiopathic recurrent implantation failure (iRIF), we conducted a retrospective cohort study of 212 iRPL couples and 66 iRIF couples who underwent PGT-A or conventional in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) treatment. The implantation rate (IR) per transfer (64.2%), clinical pregnancy rate (CPR) per transfer (57.5%), and live birth rate (LBR) per transfer (45%) of iRPL couples of the PGT-A treatment group were significantly higher (p < 0.05) than those of the conventional IVF/ICSI group (IR per transfer,38.2%; CPR per transfer,33.3%; LBR per transfer, 28.4%), whereas the pregnancy loss rate (PLR) per transfer was similar between the two groups. These effects were also significant (p < 0.05) in iRPL couples with advanced maternal age (AMA, ≥35 years), whereas no significant differences were found in clinical outcomes between the PGT-A and conventional IVF/ICSI groups in younger iRPL couples (<35 years). The cumulative clinical outcomes of iRPL couples were comparable between the PGT-A and conventional IVF/ICSI groups. No significant differences were found in any clinical outcomes between the PGT-A and conventional IVF/ICSI groups for young or AMA couples with iRIF. In conclusion, NGS-based PGT-A involving TE biopsy may be useful for iRPL women to shorten the time to pregnancy and reduce their physical and psychological burden, especially for iRPL women with AMA; however, couples with iRIF may not benefit from PGT-A treatment. Considering the small sample size of the iRIF group, further investigations with a larger sample size are needed to verify our findings.