Intrauterine exosomes are required for bovine conceptus implantation

Exosomes, extracellular vesicles, are present in uterine flushing fluids (UFs), which are involved in conceptus-endometrial interactions during peri-implantation periods. Despite several studies on intrauterine exosomes conducted, the roles conceptus and endometrial exosomes play during peri-implantation periods have not been well characterized. To investigate the effect of bovine intrauterine exosomes on conceptus implantation, exosomes isolated from bovine UFs during peri-implantation periods were subjected to global protein analysis. The analysis detected 596 exosomal proteins, including ruminants' pregnancy recognition factor IFNT, and 172 differentially expressed proteins with more than 1.5-fold changes in UFs on days 17, 20 and 22 pregnancy (day of conceptus implantation is initiated on days 19-19.5). Treatment of primary bovine endometrial epithelial cells with exosomes from day 17 UFs up-regulated the expression of apoptosis-related genes, and treatment with exosomes from day 20 and 22 UFs up-regulated the expression of adhesion molecule. Based on these findings, intrauterine exosomes should be considered as an essential constituent for successful implantation.

miR-132 serves as a diagnostic biomarker in gestational diabetes mellitus and its regulatory effect on trophoblast cell viability

BACKGROUND

Gestational diabetes mellitus (GDM) leads to poor pregnancy outcomes. Strategies that improve trophoblast cell function are important methods for GDM treatment. This study aimed to investigate the expression and diagnostic potential of microRNA-132 (miR-132) in GDM patients, and further analyzed the effects of miR-132 on HTR-8/SVneo cell proliferation.

METHODS

Quantitative real-time PCR was applied to estimate the expression of miR-132. A receiver operating characteristics curve (ROC) analysis was performed to evaluate the diagnostic value of serum miR-132 in GDM patients. In vitro regulation of miR-132 in trophoblast cell HTR-8/SVneo was achieved by cell transfection, and the effects of miR-132 on cell proliferation were assessed using CCK-8 assay.

RESULTS

Expression of miR-132 was decreased in serum and placenta tissues in GDM patients compared with the healthy women. A negative correlation was found between the serum miR-132 levels and fasting blood glucose of the GDM patients. A ROC curve shown the serum miR-132 had considerable diagnostic accuracy with an area under the curve (AUC) of 0.898. High glucose (HG) treatment induced an inhibition in HTR-8/SVneo cell proliferation and the expression of miR-132. The overexpression of miR-132 in HTR-8/SVneo cells could markedly rescued the HG - induced suppressed cell proliferation.

CONCLUSION

All the data of this study revealed the reduced expression of miR-132 in serum and placenta tissues of GDM, and serum miR-132 serves a candidate biomarker in the diagnosis of GDM. miR-132 may act a protective role against GDM via enhancing the trophoblast cell proliferation.

Protein O-fucosyltransferase 1 promotes trophoblast cell proliferation through activation of MAPK and PI3K/Akt signaling pathways

Protein O-fucosylation is an important glycosylation modification and plays an important role in embryonic development. Protein O-fucosyltransferase 1 (poFUT1) is an essential enzyme that catalyzes the synthesis of protein O-fucosylation. Our previous studies showed that poFUT1 promoted trophoblast cell migration and invasion at the fetal-maternal interface, but the role of poFUT1 in trophoblast cells proliferation remains unclear. Here, immunohistochemistry data showed that poFUT1 and PCNA levels were decreased in abortion patient's trophoblasts compared with women with normal pregnancies. Our results also showed that poFUT1 promoted trophoblast cell proliferation by CCK-8 assay and cell cycle analysis. PoFUT1 increased the phosphorylation of ERK1/2, p38 MAPK, and PI3K/Akt, while inhibitors of ERK1/2(PD98059), p38 MAPK(SB203580), and PI3K (LY294002) prevented ERK1/2, p38 MAPK, and Akt phosphorylation. Moreover, poFUT1 stimulation of trophoblast cells proliferation correlated with increased cell cycle progression by promoting cells into S-phase. The underlying mechanism involved increased cyclin D1, cyclin E, CDK 2, CDK 4, and pRb expression and decreased levels of the cyclin-dependent kinase inhibitors p21 and p27, which were blocked by inhibitors of the upstream signaling molecules MAPK and PI3K/Akt. In conclusion, poFUT1 promotes trophoblast cell proliferation by activating MAPK and PI3K/Akt signaling pathways.

Lentivirus-mediated miR-23a overexpression induces trophoblast cell apoptosis through inhibiting X-linked inhibitor of apoptosis

Preeclampsia (PE) is a pregnancy-specific disorder representing a major cause of maternal and perinatal morbidity and mortality. MicroRNAs (miRNAs) have emerged as critical regulators in PE. However, the precise role of miRNAs in PE remains poorly understood. In this study, we aimed to investigate the potential role of miR-23a and the underlying mechanism in regulating trophoblast cell apoptosis. We found a significant increase of miR-23a expression in placental tissues from PE patients. Lentivirus-mediated miR-23a overexpression significantly induced apoptosis in trophoblast cells in vitro. X-linked inhibitor of apoptosis (XIAP) was identified as a target gene of miR-23a by bioinformatics analysis and dual-luciferase reporter assay. Overexpression of miR-23a significantly inhibited XIAP expression. Knockdown of XIAP also induced trophoblast cell apoptosis. Moreover, restoration of XIAP expression significantly abolished the miR-23 overexpression-induced trophoblast cell apoptosis. Taken together, our study demonstrates that miR-23a induces trophoblast cell apoptosis by inhibiting XIAP, which may contribute to PE. Our findings provide novel insights into understanding the pathogenesis of PE and suggest a potential therapeutic target in PE.

circMAP3K4 regulates insulin resistance in trophoblast cells during gestational diabetes mellitus by modulating the miR-6795-5p/PTPN1 axis

Background

Insulin resistance (IR) during gestational diabetes mellitus (GDM) has been linked to dysregulated insulin-PI3K/Akt pathway. A defective insulin-PI3K/Akt pathway and dysregulated circular RNA (circRNA) levels have been observed in the placentas of patients with GDM; however, the mechanisms underlying this association remain unclear.

Methods

circRNAs potentially associated with GDM were selected through bioinformatics analysis and initially identified by quantitative real-time PCR (qPCR) in 9 GDM patients and 9 healthy controls, of which circMAP3K4 was further validated in additional 84 samples by qPCR. circMAP3K4 identity and localization were verified. Pearson correlation analysis was applied to evaluate the correlation between circMAP3K4 expression in the placental tissues of GDM patients and IR-related indicators. An IR model of trophoblasts was constructed using glucosamine. Interactions between miR-6795-5p and circMAP3K4 or PTPN1 were confirmed using a dual-luciferase reporter assay. The circMAP3K4/miR-6795-5p/PTPN1 axis and key markers in the insulin-PI3K/Akt pathway in placentas and trophoblasts were evaluated through qRT-PCR, immunofluorescence, and western blotting. The role of circMAP3K4 in glucose metabolism and cell growth in trophoblasts was determined using the glucose uptake and CCK8 assay, respectively.

Results

circMAP3K4 was highly expressed in the placentas of patients with GDM and the IR trophoblast model; this was associated with a dysregulated insulin-PI3K/Akt pathway. circMAP3K4 in the placentas of GDM patients was positively correlated with weight gain during pregnancy and time-glucose area under the curve of OGTT. circMAP3K4 and PTPN1 could both bind to miR-6795-5p. miR-6795-5p and PTPN1 were downregulated and upregulated, respectively, in the placentas of GDM patients and the IR trophoblast model. circMAP3K4 silencing or miR-6795-5p overexpression partially reversed the decrease in glucose uptake, inhibition in cell growth, and downregulated IRS1 and Akt phosphorylation in IR-trophoblasts; this restoration was reversed upon co-transfection with an miR-6795-5p inhibitor or PTPN1.

Conclusion

circMAP3K4 could suppress the insulin-PI3K/Akt signaling pathway via miR-6795-5p/PTPN1 axis, probably contributing to GDM-related IR.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-022-03386-8.

Characterization of the role for cadherin 6 in the regulation of human endometrial receptivity

BACKGROUND

The endometrial luminal epithelium is the first point of attachment of embryos during implantation. Failure of embryos to firmly adhere results in implantation failure and infertility. A receptive endometrial luminal epithelium is achieved through the expression of adhesion molecules in the mid-secretory phase and is a requirement for implantation. Cadherin 6 (CDH6) is an adhesion molecule localizing to the endometrial luminal epithelial cell surface in the mid-secretory/receptive phase and knockdown of CDH6 in the Ishikawa cells (receptive endometrial epithelial cell line) compromises cell integrity. However, there are no studies investigating the role of CDH6 on receptivity and infertility. This study aimed to investigate whether CDH6 is dysregulated in the endometrium of women with infertility during the receptive window and the effect of CDH6 on endometrial adhesion and receptivity.

METHODS

The expression and the localization of CDH6 in the human endometrium were determined by immunohistochemistry. Ishikawa cells were used to investigate the functional consequences of CDH6 knockdown on endometrial adhesive capacity to HTR8/SVneo (trophoblast cell line) spheroids in vitro. CDH6 knockdown was assessed by qPCR and immunoblotting. After CDH6 knockdown, the expression of type II cadherin family members and CDH6 functional partners were assessed by qPCR. Two-tailed unpaired student's t-test or one-way ANOVA as appropriate were used for statistical analysis with a significance threshold of P < 0.05.

RESULTS

A significant reduction of CDH6 immunolocalization was recorded in the luminal and glandular epithelium of endometrium from women with infertility (P < 0.05) compared to fertile group respective cellular compartments in the mid-secretory phase. Functional analysis using Ishikawa cells demonstrated that knockdown of CDH6 (treated with 50 nM CDH6 siRNA) significantly reduced epithelial adhesive capacity (P < 0.05) to HTR8/SVneo spheroids compared to control and other type II cadherin family members likely failed to compensate for the loss of CDH6. The expression levels of CDH6 functional partners, catenin family members were not changed after CDH6 knockdown in Ishikawa cells.

CONCLUSION

Together, our data revealed that CDH6 was dysregulated in the endometrium from women with infertility and altered Ishikawa cell adhesive capacity. Our study supports a role for CDH6 in regulating endometrial adhesion and implantation.

Circ_0085296 suppresses trophoblast cell proliferation, invasion, and migration via modulating miR-144/E-cadherin axis

BACKGROUND

Circular RNAs (circRNAs) have been revealed to be important regulators in the biological behavior of cells, and aberrant circRNAs may be associated with the etiology of pre-eclampsia (PE). However, the role and underlying molecular mechanisms of circ_0085296 in PE remain unclear.

METHODS

The expression of circ_0085296, microRNA (miR)-144, and E-cadherin was detected using quantitative real-time polymerase chain reaction and western blot, respectively. Cell proliferation, migration, and invasion were analyzed by cell counting kit-8, colony formation and transwell assay. The interaction between miR-144 and circ_0085296 or E-cadherin was analyzed by the dual-luciferase reporter assay and pull-down assay.

RESULTS

Circ_0085296 was elevated in PE placental tissues, knockdown of circ_0085296 promoted trophoblast cell proliferation, invasion, and migration, while circ_0085296 up-regulation showed opposite effects. MiR-144 was down-regulated in PE placental tissues, and restoration of miR-144 induced proliferation, invasion, and migration in trophoblast cells. Further mechanistic analysis found miR-144 directly bound to circ_0085296 and E-cadherin, and circ_0085296 functioned as a sponge of miR-144 to regulate E-cadherin expression. Furthermore, miR-144 inhibition or E-cadherin overexpression attenuated the effectsof circ_0085296 on cell processes in trophoblast cells.

CONCLUSION

Circ_0085296 inhibited trophoblast cell proliferation, invasion, and migration via regulating miR-144/E-cadherin axis, providing a novel insight into the pathogenesis of PE and a new prospective therapeutic target for PE patients.

Down-regulated expressed protein HMGB3 inhibits proliferation and migration, promotes apoptosis in the placentas of fetal growth restriction

Fetal growth restriction (FGR) is one of the major complications of pregnancy, which can lead to serious short-term and long-term diseases. High-mobility group box 3 (HMGB3) has been found to contribute to the development of many cancers. However, the role of HMGB3 in the pathogenesis of FGR is blank. Here, we measured the expression level of HMGB3 in the placenta tissues of six normal pregnancies and five FGR patients by western blotting and quantitative real-time polymerase chain reaction (qRT-PCR). CCK8 assay, transwell assay and flow cytometry were used to detect the functional effects of overexpression and silencing of HMGB3 on the HTR8/SVneo trophoblast cell line. The results showed that the protein levels of HMGB3 were significantly decreased in FGR placentas compared to normal controls, while mRNA levels of HMGB3 were not significantly altered. Furthermore, when overexpressed of protein HMGB3 of the trophoblast cells, the proliferation and migration abilities were significantly promoted, and the apoptosis abilities of these cells were statistically inhibited. Cell functional experiments showed the opposite results when the expression of HMGB3 was silent. And the expression of cell function-related genes PCNA, Ki67, Tp53, Bax, MMP-2 and E-cadherin was observed to show corresponding changes by qRT-PCR. The results of mass spectrometry showed that HMGB3 may directly or indirectly interact with 71 proteins. In summary, our results indicated that HMGB3 might be of very great significance to the pathogenesis of FGR and might play the role by leading the dysfunction of placental villous trophoblast cells and through the interaction with some other proteins.

lncRNA SNHG14 involved in trophoblast cell proliferation, migration, invasion and epithelial-mesenchymal transition by targeting miR-330-5p in preeclampsia

Preeclampsia (PE), a pregnancy-specific disease, has become one of the leading causes of maternal and neonatal morbidity and mortality. Pathogenesis of PE has still not been fully addressed and there is a great need to develop early diagnosis markers and effective therapy. This study aimed to determine if lncRNA SNHG14 has a protective effect on placental trophoblast and prevents PE. SNHG14 levels in the peripheral blood from patients with PE or from women with healthy pregnancies were detected using RT-qPCR. The relationship between SNHG14 and miR-330-5p was determined using a dual-luciferase reporter assay. In addition, cell proliferation and cell cycle were evaluated by performing CCK8 assays and flow-cytometric analysis, respectively. Wound-healing and transwell assays were performed to assess cell migration and invasion ability. lncRNA SNHG14 was downregulated in PE patients; it was involved in trophoblast proliferation and regulated cell proliferation during G1/S transition. In addition, lncRNA SNHG14 promoted migration, invasion and epithelial-mesenchymal transition (EMT) in HTR-8/SVneo cells. Luciferase reporter assay indicated that lncRNA SNHG14 served as a molecular sponge for miR-330-5p and negatively regulated miR-330-5p expression in PE. Furthermore, the effects of silenced SNHG14 on trophoblast proliferation, migration, invasion and EMT were reversed by addition of miR-330-5p inhibitor, suggesting that in PE lncRNA SNHG14 functions by competitively binding to miR-330-5p. Taken together, the current study demonstrated that in PE lncRNA SNHG14 is a vital regulator by binding to miR-330-5p. SNHG14 might serve as a therapeutic application in PE progression.

Silencing lncRNA-DGCR5 increased trophoblast cell migration, invasion and tube formation, and inhibited cell apoptosis via targeting miR-454-3p/GADD45A axis

Long noncoding RNA (lncRNA)-DGCR5 has been recognized as a potential tumor progression regulator, while its expression and specific functions in preeclampsia (PE) development remain unveiled. The expressions of miR-454-3p, lncRNA-DiGeorge syndrome critical region gene 5 (DGCR5) and growth arrest and DNA damage protein-inducible 45A (GADD45A) in placental tissues from PE patients or HTR-8/SVneo cells were assessed by Western blot or qRT-PCR. Dual-luciferase reporter assay determined the binding relations between miR-454-3p and GADD45A and between miR-454-3p and lncRNA-DGCR5. The viability, apoptosis, migration, invasiveness and tube formation of HTR-8/SVneo cell were evaluated using cell counting kit (CCK)-8, Annexin-V/Propidium iodide staining, wound healing, transwell and tube formation assays, respectively. miR-454-3p was low-expressed in PE tissue, and upregulation of miR-454-3p increased viability and promoted migration, invasion and tube formation in HTR-8/SVneo cells while inhibiting apoptosis. Then, miR-454-3p was found to directly target GADD45A which was high-expressed in PE tissues. Overexpressing GADD45A decreased the viability and inhibited the migration, invasion and tube formation of HTR-8/SVneo cells while enhancing apoptosis, and it neutralized the effect of miR-454-3p upregulation. In turn, miR-454-3p upregulation reversed the effect of GADD45A overexpression. Meanwhile, miR-454-3p could also target lncRNA-DGCR5. Silencing lncRNA-DGCR5 increased miR-454-3p expression and cell viability and promoted migration, invasion and tube formation in HTR-8/SVneo cells while inhibiting apoptosis, and it counteracted the effect of miR-454-3p downregulation. As usual, miR-454-3p downregulation reversed the effect of lncRNA-DGCR5 silencing. To conclude, silencing lncRNA-DGCR5 increased viability, promoted migration, invasion and tube formation, and inhibited apoptosis in HTR-8/SVneo cells by rescuing the inhibition of GADD45A expression caused by miR-454-3p.

HAI-1 regulates placental folds development by influencing trophoblast cell proliferation and invasion in pigs

Fetal development is critically dependent on the efficiency of the placenta. Porcine trophoblast cell proliferation and invasion have crucial roles in placental fold development, which is one of the essential events determining placental efficiency. The membrane serine proteinase inhibitor hepatocyte growth factor activator inhibitor-1 (HAI-1) can regulate cellular invasion and motility in different types of epithelial cells, including trophoblast cells in mice. This work used quantitative polymerase chain reaction (qPCR) and immunohistochemistry to compare the expression level and location of HAI-1 in the placenta on gestational days 26, 50, and 95 in Yorkshire and Meishan pigs. The role of HAI-1 in porcine trophoblast cell (PTr2) proliferation, invasion, and migration in vitro was investigated by analyzing the effects of HAI-1 gene silencing or overexpression. Polymorphism in the HAI-1gene was detected to determine associations between the genotype and piglet birth weight in 400 healthy pure-bred Yorkshire piglets. qPCR results showed that HAI-1 mRNA levels significantly increased (P < 0.01) between gestational days 26 and 50 and then decreased (P < 0.01) between days 50 and 95 in both Meishan and Yorkshire pigs. Immunohistochemical analysis showed that HAI-1 protein was strongly expressed by the high columnar trophoblast cells located at the top of the placental folds with low proliferative and invasion capacities. However, it was expressed at very low levels in cuboidal trophoblast cells located at the side and base of the placental folds with high proliferative and invasion capacities. In vitro experiments indicated that HAI-1 had the ability to reduce the proliferation, invasion and migration of trophoblast cells. In addition, one single-nucleotide polymorphism (SNP) of HAI-1 showed a significant association (P < 0.05) with piglet birth weight. These results revealed that HAI-1 could be a vital molecule in placental folds development by regulating trophoblast proliferation and invasion in pigs.

Polymorphism in killer cell immunoglobulin-like receptors and human leukocyte antigen-c and predisposition to preeclampsia in Ethiopian pregnant women population

INTRODUCTION

Preeclampsia (PE) is a human specific pregnancy-related syndrome of unknown etiology that affects 2-8 % of pregnancies. Polymorphism in maternal Killer Cell Immunoglobulin-like Receptors (KIRs) and the ligand fetal Human Leukocyte Antigen-C (HLA-C) may predispose pregnant mothers for PE due to defective trophoblast invasion into the maternal decidua. Our study aimed to investigate the association between maternal KIR and fetal HLA-C polymorphism and PE in Ethiopian pregnant women.

METHODS

We included a total of 288 (157 controls and 131 PE cases) in a case-controls study at Adama Regional Referral Hospital, Ethiopia. The KIR and HLA-C genotyping was done using traditional polymerase chain reaction on genomic DNA extracted form maternal venous and cord blood followed by 2% agarose gel electrophoresis.

RESULTS

The statistical associations between variables were evaluated using Pearson's Chi-square test. P < 0.05, with 95 % confidence interval was considered statistically significant. A significant association was observed between the KIR2DS1 and PE, with a higher frequency (60.5 %) of the gene in the control group. Similarly, a significant association was observed between KIR AA genotype and PE, with a higher frequency (38.2 %) of this genotype in the PE group. Ethiopians share the same risk genotype for PE as seen in previous African and European studies, namely homozygosity of a maternal KIR AA genotype. However, Ethiopians differ from other East African populations by sharing the same protective KIR2DS1 gene as Europeans.

Azithromycin treatment is able to control the infection by two genotypes of Toxoplasma gondii in human trophoblast BeWo cells

Trophoblast infection by Toxoplasma gondii plays a pivotal role in the vertical transmission of toxoplasmosis. Here, we investigate whether the antibiotic therapy with azithromycin, spiramycin and sulfadiazine/pyrimethamine are effective to control trophoblast infection by two Brazilian T. gondii genotypes, TgChBrUD1 or TgChBrUD2. Two antibiotic protocols were evaluated, as follow: i) pre-treatment of T. gondii-tachyzoites with selected antibiotics prior trophoblast infection and ii) post-treatment of infected trophoblasts. The infection index/replication and the impact of the antibiotic therapy on the cytokine milieu were characterized. It was observed that TgChBrUD2 infection induced lower infection index/replication as compared to TgChBrUD1. Regardless the therapeutic protocol, azithromycin was more effective to control the trophoblast infection with both genotypes when compared to conventional antibiotics. Azithromycin induced higher IL-12 production in TgChBrUD1-infected cells that may synergize the anti-parasitic effect. In contrast, the effectiveness of azithromycin to control the TgChBrUD2-infection was not associated with the IL-12 production. BeWo-trophoblasts display distinct susceptibility to T. gondii genotypes and the azithromycin treatment showed to be more effective than conventional antibiotics to control the T. gondii infection/replication regardless the parasite genotype.

ADAM7 promotes the proliferation and invasion in trophoblast cells

ADAMs are members of the metzincin family of zinc-dependent metalloproteinases, which play a key role in the proteolytic degradation of the extracellular matrix to invade cells. It is well known that ADAMs are involved in regulating the invasion of trophoblast cells. But the function and underlying mechanism of ADAM7 in trophoblast cells is still unknown. ADAM7 knockdown strongly inhibited HTR-8 and B6Tert-1 cells proliferation, migration and invasion, while ADAM7 overexpression reversed. The expression of protein pro-caspase 3 and pro-caspase 9 was not affected by either ADAM7 knockdown or overexpression in HTR-8 and B6Tert-1 cells, while the expression of active-caspase 3 and active-caspase 9 was strongly increased in ADAM7 silenced cells and significant decreased in ADAM7 overexpressed cells. We also found that the phosphorylation of p38MAPK was significantly inhibited in ADAM7 silenced cells while it was significantly induced in ADAM7 overexpressed cells. Metformin HCl could reverse the inhibitory effects of ADAM7 knockdown on the p38MAPK signaling pathway and the proliferation of HTR-8 and B6Tert-1 cells. ADAM7 plays a positive role in trophoblast cells, which may be attributed to regulation of the p38MAPK signaling pathway. SIGNIFICANCE: It is necessary to further study the molecular mechanism of trophoblast cells proliferation, migration and invasion, and develop a more effective treatment to preeclampsia. This research might provide a new target for further research in this area.

AK002210 promotes the proliferation, migration and invasion of trophoblast cell through regulating miR-590/NAIP signal axis

Preeclampsia (PE) is a pregnancy-related syndrome and has become the leading cause of maternal and neonatal morbidity and mortality. LncRNA has been elucidated to play critical roles in the phenotype of trophoblast cells. However, the effect of AK002210 has not been reported. We aim to investigate the effect of AK002210 on the phenotype of trophoblast cells. Quantitative reverse transcription PCR was used to assess the gene expression. CCK-8 assay was used to evaluate the cell proliferation. Transwell assay was performed to detect the migration and invasion of trophoblast cells. Luciferase assay and rescue experiment were carried out to verify the interaction between miR-590-3p and AK002210 as well as NLR family apoptosis inhibitory protein (NAIP). The results revealed that AK002210 promoted the proliferation, migration and invasion of trophoblast cell while AK002210 knockdown inhibited that. Mechanically, we found that AK002210 was targeted by miR-590-3p. Moreover, miR-590-3p also directly targets NAIP which served as a ceRNA of AK002210. Rescue experiment showed that miR-590-3p reversed the effect of AK002210 which further confirmed their interaction. Moreover, AK002210 was proved to participated in the regulation of ERK/MMP-2 signal axis. In conclusion, we found that AK002210 knockdown may play a critical role in the progression of PE via miR-590-3p/NAIP and ERK/MMP signaling. It has potential to be a novel prognostic or therapeutic marker of PE.

Hypoxia-induced DEC1 mediates trophoblast cell proliferation and migration via HIF1α signaling pathway

In early pregnancy, hypoxia is a typical extrinsic factor that regulates EVT functions including proliferation, migration and invasion which are essential for a successful pregnancy. Human differentiated embryonic chondrocyte-expressed gene 1 (DEC1), a hypoxia-regulated gene, has been reported to be overexpressed in several types of cancers. Given that the placenta and the cancer share several similarities with respect to their capacity to proliferate and invade adjacent tissues, we focused on the role of DEC1 on trophoblast function in a physiologically hypoxic environment, which may be associated with unexplained recurrent spontaneous abortion (URSA).In our study, we measured the expression of HIF-1α and DEC1 in first-trimester villi through real-time-PCR (RT-PCR) and immunohistochemical analysis. in vitro, DEC1 expression was downregulated in trophoblast cells via DEC1-specific shRNA plasmid transfection. The expression of DEC1 and HIF-1α was detected via western blotting and RT-PCR analysis. The proliferation and migration of HTR-8/SVneo cells were assayed using CCK-8 and Transwell migration assays, respectively.Our results indicated that the expression of DEC1 was significantly reduced in villi of URSA compared to that in normal pregnant women. in vitro, hypoxia induced the expression of HIF-1ɑ and DEC1 and upregulated proliferation and migration of the HTR-8/SVneo cells. Knockdown of DEC1 inhibited proliferation and migration of HTR-8/SVneo cells exposure to hypoxia. Furthermore, inhibition of HIF1α expression resulted in a significant decrease in DEC1. These findings illustrate that hypoxia-induced DEC1 expression promotes trophoblast cell proliferation and migration through the HIF1α signaling pathway, which plays an important role during placentation.

miR-338-5p Targets Epidermal Growth Factor-Containing Fibulin-Like Extracellular Matrix Protein 1 to Inhibit the Growth and Invasion of Trophoblast Cells in Selective Intrauterine Growth Restriction

Selective intrauterine growth restriction (sIUGR) is a disorder of monochorionic (MC) twin pregnancies. However, the underlying mechanism remains largely unknown. Trophoblast cells are the major component of the placenta. Dysfunction of trophoblast cells is associated with placental dysfunction. Our previous study identified miR-338-5p is downregulated in placenta tissues sharing larger twins of sIUGR. In the present study, we aimed to investigate the role of miR-338-5p in trophoblast cells and explored its target. Our results further indicated that miR-338-5p was downregulated in placental tissues supporting larger twins of sIUGR, whereas epidermal growth factor-containing fibulin-like extracellular matrix protein 1 (EFEMP1) was upregulated. Moreover, miR-338-5p overexpression suppressed the growth and invasion of trophoblast cells. Importantly, results from luciferase reporter assay demonstrated that miR-338-5p bound on the 3'-UTR of EFEMP1. miR-338-5p suppressed the growth and invasion of trophoblast cells via targeting EFEMP1. Further, miR-338-5p/EFEMP1 might disrupt the function of trophoblast cells via inhibiting the phosphorylation of AKT.

Toxicological Effects of BPDE on Dysfunctions of Female Trophoblast Cells

Polycyclic aromatic hydrocarbons (PAHs) are widely spread persistent environmental toxicants. Its typical representative benzo[a]pyrene (BaP) is a human carcinogen. BaP can pass through the placental barrier and is finally metabolized into benzo[a]pyren-7, 8-dihydrodiol-9, 10-epoxide (BPDE). BPDE can form DNA adducts, which directly affect the female reproductive health. Based on the special physiological functions of trophoblast cells and its important effect on normal pregnancy, this chapter describes the toxicity and molecular mechanism of BPDE-induced dysfunctions of trophoblast cells. By affecting the invasion, migration, apoptosis, proliferation, inflammation, and hormone secretion of trophoblast cells, BPDE causes diseases such as choriocarcinoma, intrauterine growth restriction, eclampsia, and abortion. In the end, it is expected to provide a scientific basis and prevention approach for women's reproductive health and decision-making basis for the formulation of environmental health standards.

Macrophage-stimulating protein is decreased in severe preeclampsia and regulates the biological behavior of HTR-8/SVneo trophoblast cells

Preeclampsia (PE) is a major challenge for obstetricians. There is no effective way to block the development of PE other than terminating the pregnancy. The biological behavior of trophoblast cells, which are similar to cancer cells, may be closely related to the onset of PE. The vital role of macrophage-stimulating protein (MSP) in the development and progression of cancer has been recognized, while a role for this protein in PE has rarely been reported. This study aimed to explore whether MSP affects severe PE (sPE) and, if so, to characterize the mechanism. Patient information, blood samples and/or placental tissues were collected. An enzyme-linked immunosorbent assay (ELISA) was used to determine the plasma MSP concentration. The relationships between the plasma MSP concentration and clinical characteristics were analyzed. Immunofluorescence was performed to localize MSP in placental tissues. Western blotting and reverse transcription quantitative polymerase chain reaction (RT-qPCR) were used to determine MSP protein and mRNA expression in placental tissues. MSP was overexpressed or underexpressed in the trophoblastic cell line HTR-8/SVneo by lentiviral transfection and the proliferation, apoptosis, migration, invasion and angiogenesis of cells were detected. MSP was downregulated in sPE, and the underexpression of MSP inhibited HTR-8/SVneo cell proliferation, migration, invasion and angiogenesis. We further verified that MSP affects the biological behavior of trophoblast cells through the β-catenin/ZEB1 signaling pathway. These results suggest that decreased MSP in the blood and placental tissues of patients with sPE, especially those with early-onset sPE, leads to reduced trophoblast cell invasion, which plays an important role in the pathogenesis of PE.

MAML1: a coregulator that alters endometrial epithelial cell adhesive capacity

BACKGROUND

Abnormalities in endometrial receptivity has been identified as a major barrier to successful embryo implantation. Endometrial receptivity refers to the conformational and biochemical changes occurring in the endometrial epithelial layer which make it adhesive and receptive to blastocyst attachment. This takes place during the mid-secretory phase of woman's menstrual cycle and is a result of a delicate interplay between numerous hormones, cytokines and other factors. Outside of this window, the endometrium is refractory to an implanting blastocyst. It has been shown that Notch ligands and receptors are dysregulated in the endometrium of infertile women. Mastermind Like Transcriptional Coactivator 1 (MAML1) is a known coactivator of the Notch signaling pathway. This study aimed to determine the role of MAML1 in regulating endometrial receptivity.

METHODS

The expression and localization of MAML1 in the fertile human endometrium (non-receptive proliferative phase versus receptive mid-secretory phase) were determined by immunohistochemistry. Ishikawa cells were used as an endometrial epithelial model to investigate the functional consequences of MAML1 knockdown on endometrial adhesive capacity to HTR8/SVneo (trophoblast cell line) spheroids. After MAML1 knockdown in Ishikawa cells, the expression of endometrial receptivity markers and Notch dependent and independent pathway members were assessed by qPCR. Two-tailed unpaired or paired student's t-test were used for statistical analysis with a significance threshold of P < 0.05.

RESULTS

MAML1 was localized in the luminal epithelium, glandular epithelium and stroma of human endometrium and the increased expression identified in the mid-secretory phase was restricted only to the luminal epithelium (P < 0.05). Functional analysis using Ishikawa cells demonstrated that knockdown of MAML1 significantly reduced epithelial adhesive capacity (P < 0.01) to HTR8/SVneo (trophoblast cell line) spheroids compared to control. MAML1 knockdown significantly affected the expression of classical receptivity markers (SPP1, DPP4) and this response was not directly via hormone receptors. The expression level of Hippo pathway target Ankyrin repeat domain-containing protein 1 (ANKRD1) was also affected after MAML1 knockdown in Ishikawa cells.

CONCLUSION

Our data strongly suggest that MAML1 is involved in regulating the endometrial adhesive capacity and may facilitate embryo attachment, either directly or indirectly through the Notch signaling pathway.

RhoGDI1 interacts with PHLDA2, suppresses the proliferation, migration, and invasion of trophoblast cells, and participates in the pathogenesis of preeclampsia

Preeclampsia (PE) is a pregnancy-associated disease, which is the major cause of mortality on maternity and perinatal infants. It is hypothesized that PE is a consequence of the dysfunction of the trophoblast cells. Pleckstrin homology-like domain, family A, member 2 (PHLDA2) was shown to inhibit the proliferation, migration, and invasion of trophoblast cells in our previous studies. However, the mechanism by which PHLDA2 affects trophoblast cell function has not been clarified. In the current study, co-immunoprecipitation (Co-IP) with mass spectroscopy analysis was used to explore the proteins that interacted with PHLDA2. A total of 291 candidate proteins were found to be associated with PHLDA2. The interaction between PHLDA2 and Rho guanine nucleotide dissociation inhibitor (RhoGDI) 1 was identified by Co-IP and immunofluorescence staining. Western blot analysis indicated that overexpression of PHLDA2 resulted in upregulation of the RhoGDI1 protein levels, which were stabilized in the presence of cycloheximide. Similarly, overexpression of RhoGDI1 promoted PHLDA2 expression and its stability. Furthermore, pull-down and Co-IP results indicated that PHLDA2 repressed the activity of Rho guanosine triphosphate hydrolase family proteins by regulating RhoGDI1 expression. In addition, RhoGDI1 expression was upregulated in the placental tissues of patients with PE. The effects of the suppression of PHLDA2 expression on proliferation, migration, and invasion of trophoblast cells were partly abrogated following knockdown of RhoGDI1. Taken together, the data indicated that RhoGDI1 mediated regulation of PHLDA2 on the biological behavior of trophoblast cells and may participate in the pathophysiology of PE.

[Effects of PFOS on inflammatory factors in human placental trophoblast cells]

Objective: To investigate the effect of perfluorooctane sulfonate (PFOS) on inflammatory factors in human placental trophoblast (HTR-8/Svneo) cells. Methods: HTR-8/Svneo cells were exposed to different concentrations of PFOS (0, 0.01, 0.1, 1.0 mg/L) for 24 h, and the cell survival rates were measured by CCK8. Secretion levels of interleukin-6 (IL-6) , tumor necrosis factor-alpha (TNF-α) and interleukin-10 (IL-10) were detected by ELISA. The mRNA expressions of IL-6, TNF-α and IL-10 were detected by fluorescence quantitative PCR. One-way ANOVA was used to analyse the expressions of inflammatory factors. Results: Compared with the control group, the survival rates of 0.1 and 1.0 mg/L PFOS groups were significantly decreased (P<0.05) . Compared with the control group, the secretion levels of IL-6 were decreased in the 0.01, 0.1 and 1.0 mg/L PFOS groups (P<0.05) , the concentrations of TNF-α were increased in the 0.01 and 1.0 mg/L PFOS groups (P<0.05) , and the concentrations of IL-10 were increased in the 0.1 and 1.0 mg/L PFOS groups (P<0.05) . Compared with the control group, the expressions of IL-6 mRNA were increased in the 0.1 and 1.0 mg/L PFOS groups (P<0.05) , and the expressions of IL-10 mRNA were decreased in the 0.01 mg/L, 0.1 mg/L and 1.0 mg/L PFOS groups (P<0.05) . Conclusion: PFOS can induce changes in the secretion levels of inflammatory cytokines in HTR-8/Svneo cells, resulting in decreased activity of placental trophoblast cells and abnomal placental function.

Programmed cell death protein 1 promotes hepatitis B virus transmission through the regulation of ERK1/2-mediated trophoblasts differentiation

PURPOSE

The purpose of our research is to evaluate the mechanism of PD-1 in the promotion of HBV transmission.

METHODS

HBV was used to infect two human choriocarcinoma cell line, including JEG-3, as well as BeWo. We used PCR and western blotting to detect PD-1 gene and protein expression levels in cells. Stable knockdown of the PD-1 gene in JEG-3 cells was obtained by lentiviral transfection. Trophoblast cell proliferation was evaluated using CCK8 and flow cytometry. The concentration of HBV antibody in the cell supernatant was measured by ELISA. DNA was then extracted from the cells and the copy number of the HBV virus was detected by PCR. Finally, ERK1/2 expression was detected by western blot.

RESULTS

High PD-1 gene expression in HBV-infected trophoblasts and the knockdown of PD-1 gene can, respectively, improve the proliferation of HBV-infected trophoblasts and reduce viral replication in trophoblasts. In addition, PD-1 and ERK1/2 proteins were co-expressed in HBV-infected trophoblasts and inhibited the activation of ERK1/2 pathway in HBV-infected trophoblasts. ERK1/2 expression significantly increased after PD-1 knockdown. Therefore, PD-1 might be an important protein in trophoblast cells infected with HBV.

CONCLUSIONS

PD-1 promoted HBV transmission through regulating ERK1/2-mediated trophoblasts differentiation. Therefore, our research may provide new ideas and methods for preventing mother-to-child transmission of HBV infection during pregnancy.

Recognized trophoblast-like cells conversion from human embryonic stem cells by BMP4 based on convolutional neural network

The use of models of stem cell differentiation to trophoblastic cells provides an effective perspective for understanding the early molecular events in the establishment and maintenance of human pregnancy. In combination with the newly developed deep learning technology, the automated identification of this process can greatly accelerate the contribution to relevant knowledge. Based on the transfer learning technique, we used a convolutional neural network to distinguish the microscopic images of Embryonic stem cells (ESCs) from differentiated trophoblast -like cells (TBL). To tackle the problem of insufficient training data, the strategies of data augmentation were used. The results showed that the convolutional neural network could successfully recognize trophoblast cells and stem cells automatically, but could not distinguish TBL from the immortalized trophoblast cell lines in vitro (JEG-3 and HTR8-SVneo). We compare the recognition effect of the commonly used convolutional neural network, including DenseNet, VGG16, VGG19, InceptionV3, and Xception. This study extends the deep learning technique to trophoblast cell phenotype classification and paves the way for automatic bright-field microscopic image analysis of trophoblast cells in the future.

JPT2 in subclinical hypothyroidism-related miscarriage as a transcription co-factor: involvement of LEPR/STAT3 activation

BACKGROUND AND PURPOSE

Subclinical hypothyroidism (SCH) has been identified to be associated with implantation failure, in which the dysfunction of trophoblast cells is involved. In this study, the transcriptomics of aborted placenta from SCH rats were analyzed. Jupiter microtubule-associated homolog 2 (JPT2) was downregulated in the aborted placenta. This study aims to investigate its role in SCH-associated miscarriage.

METHODS

Spontaneous abortion was observed in SCH rats generated by thyroidectomy combined with levothyroxine administration. The transcriptomics analysis was performed using aborted placenta. Afterward, the effects of JPT2 on trophoblast cells were explored using gain-and loss-of-function experiments.

RESULTS

Transcriptomics analysis showed 1286 downregulated genes and 2300 upregulated genes in the aborted placenta, and JPT2 was significantly downregulated in the aborted placenta from SCH rats. Afterward, gain-and loss-of-function experiments exhibited that overexpression of JPT2 promoted the proliferation, migration, invasion, spheroid formation of HTR-8/SVneo trophoblast cells and their attachment to endometrial stromal cells, while these biological behaviors were suppressed by JPT2 knockdown. Furthermore, JPT2 accelerated the transcription of leptin receptor (LEPR), and activated signal transducer and activator of transcription 3 (STAT3) signal in a transcription factor AP-2γ-dependent manner. In addition, silencing of LEPR abolished the role of JPT2.

CONCLUSION

Our results revealed that JPT2, which was downregulated in the aborted placenta from SCH rats, promoted proliferation, migration, invasion, spheroid formation, and attachment of trophoblast cells via regulating LEPR/STAT3 axis as a transcription co-factor. It is indicated that low expression of JPT2 may contribute to the abortion in individuals with SCH.