Dysfunction of WNT4/WNT5A in deciduas: possible relevance to the pathogenesis of preeclampsia

The mutation of NSUN5 R295C promotes preeclampsia by impairing decidualization through downregulating IL-11Rα

Preeclampsia (PE) is a pregnancy-specific hypertensive disorder that severely impairs maternal and fetal health. However, its pathogenesis remains elusive. NOP2/Sun5 (NSUN5) is an RNA methyltransferase. This study discovered a significant correlation between rs77133388 of NSUN5 and PE in a cohort of 868 severe PE patients and 982 healthy controls. To further explore this association, the researchers generated single-base mutant mice (NSUN5 R295C) at rs77133388. The pregnant NSUN5 R295C mice exhibited PE symptoms. Additionally, compared to the controls, the decidual area of the placenta was significantly reduced in NSUN5 R295C mice, and their decidualization was impaired with a significantly decrease in polyploid cell numbers after artificially induced decidualization. The study also found a decrease in phosphorylated JAK2, STAT3, and IL-11Rα, Cyclin D3 expression in NSUN5 R295C mice. Overall, these findings suggest that NSUN5 mutation potentially alters decidualization through the IL-11Rα/JAK2/STAT3/Cyclin D3 pathway, ultimately impairing placental development and contributing to PE occurrence.

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

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

Establishment and validation of a predictive model of preeclampsia based on transcriptional signatures of 43 genes in decidua basalis and peripheral blood

Preeclampsia (PE) has an increasing incidence worldwide, and there is no gold standard for prediction. Recent progress has shown that abnormal decidualization and impaired vascular remodeling are essential to PE pathogenesis. Therefore, it is of great significance to analyze the decidua basalis and blood changes of PE to explore new methods. Here, we performed weighted gene co-expression network analysis based on 9553 differentially expressed genes of decidua basalis data (GSE60438 includes 25 cases of PE and 23 non-cases) from Gene Expression Omnibus to screen relevant module-eigengenes (MEs). Among them, MEblue and MEgrey are the most correlated with PE, which contains 371 core genes. Subsequently, we applied the logistic least absolute shrinkage and selection operator regression, screened 43 genes most relevant to prediction from the intersections of the 371 genes and training set (GSE48424 includes 18 cases of PE and 18 non-cases) genes, and built a predictive model. The specificity and sensitivity are illustrated by receiver operating characteristic curves, and the stability was verified by two validation sets (GSE86200 includes 12 cases of PE and 48 non-cases, and GSE85307 includes 47 cases of PE and 110 non-cases). The results demonstrated that our predictive model shows good predictions, with an area under the curve of 0.991 for the training set, 0.874 and 0.986 for the validation sets. Finally, we found the 43 key marker genes in the model are closely associated with the clinically accepted predictive molecules, including FLT1, PIGF, ENG and VEGF. Therefore, this predictive model provides a potential approach for PE diagnosis and treatment.

DCAF13 is essential for the pathogenesis of preeclampsia through its involvement in endometrial decidualization

Preeclampsia (PE) is a syndrome that occurs during pregnancy and affects more than 8 million mother-infant pairs each year. Most previous studies on the pathogenesis of PE have focused on the placenta. However, decidualization is the basis for placentation and subsequent development. The CRL4 (Cullin 4-RING E3 ubiquitin ligase) complex ubiquitinates and degrades substrates, while DCAF13 (DDB1 and CUL4-associated factor 13) is a component and substrate receptor of this complex, which recognizes and recruits the complex different substrates. DCAF13 plays a major role in the maintenance of follicles and the development of oocytes. However, its role in subsequent pregnancies remains unclear. In the present study, we first investigated DCAF13 levels in the decidua of PE patients and found that it is significantly lower than that of normal pregnant women. Second, we found that DCAF13 expression increases during decidualization, and reducing expression of DCAF13 by siRNA prevents decidualization. Third, in vivo experiments in mice further revealed that Dcaf13 expression increases with decidualization. Finally, we generated and found that uteri of pseudopregnant conditional Dcaf13 knockout mice fails to undergo decidualization. Therefore, we propose that DCAF13 plays a key role in decidualization. Abnormal expression of DCAF13 affects the decidualization process, which is likely involved in the occurrence and development of PE.

Elevated trophoblastic Siglec6 contributes to the impairment of vascular endothelial cell functions by downregulating Wnt6/β-catenin signaling in preeclampsia

Preeclampsia (PE), a systemic vascular disorder, is the leading cause of maternal and perinatal morbidity and mortality, and its pathogenesis has yet to be fully elucidated. Siglec6, a transmembrane protein, is highly expressed in human placental trophoblasts, and previous studies have shown that Siglec6 overexpression correlates with PE, but the role of Siglec6 during PE progression is unknown. Here, we demonstrated that the mRNA and protein expression levels of Siglec6 were upregulated in early-onset PE placentas compared with uncomplicated pregnancies, and Siglec6 was primarily located in syncytiotrophoblasts (STBs) and extravillous trophoblasts (EVTs). Moreover, our results showed that chemical reagent-induced HIF-1α accumulation promoted the mRNA and protein levels of Siglec6 in HTR8/SVneo and BeWo cells. Although Siglec6 overexpression did not affect HTR8/SVneo cell proliferation, migration, and invasion, the conditional medium derived from the Siglec6 overexpressed HTR8/SVneo cells (Siglec6-OE-CM) significantly impaired the proliferation, migration, invasion, and tube formation of human umbilical vein endothelial cells (HUVECs). Subsequently, the transcriptome sequencing results revealed that Siglec6 overexpression led to the downregulation of Wnt6 in HTR8/SVneo cells, which was further confirmed by qPCR and ELISA. Recombinant human Wnt6 reversed Siglec6-OE-CM-mediated suppression of HUVEC functions by reactivating the Wnt/β-catenin signaling pathway. Altogether, our study found that elevated trophoblastic Siglec6 contributed to the impairment of vascular endothelial cell functions by downregulating Wnt6/β-catenin signaling.

Mouse fetal growth restriction through parental and fetal immune gene variation and intercellular communications cascade

Fetal growth restriction (FGR) affects 5-10% of pregnancies, and can have serious consequences for both mother and child. Prevention and treatment are limited because FGR pathogenesis is poorly understood. Genetic studies implicate KIR and HLA genes in FGR, however, linkage disequilibrium, genetic influence from both parents, and challenges with investigating human pregnancies make the risk alleles and their functional effects difficult to map. Here, we demonstrate that the interaction between the maternal KIR2DL1, expressed on uterine natural killer (NK) cells, and the paternally inherited HLA-C*0501, expressed on fetal trophoblast cells, leads to FGR in a humanized mouse model. We show that the KIR2DL1 and C*0501 interaction leads to pathogenic uterine arterial remodeling and modulation of uterine NK cell function. This initial effect cascades to altered transcriptional expression and intercellular communication at the maternal-fetal interface. These findings provide mechanistic insight into specific FGR risk alleles, and provide avenues of prevention and treatment.

LncRNA MALAT1 promotes decidualization of endometrial stromal cells via sponging miR-498-3p and targeting histone deacetylase 4

Decidualization of human endometrial stromal cells (hESCs) is important for the maintenance of a successful pregnancy. Histone deacetylase 4 (HDAC4) was reported to be involved in the dysfunction of decidua-derived mesenchymal stem cells. However, the role of HDAC4 underlying decidualization of hESCs remains unclear. We intended to explore the function and molecular mechanism of HDAC4 in hESCs. In vitro expansion of hESCs using a serum-free medium was used to confirm the characteristics of hESCs. Gene expression in hESCs was evaluated by reverse transcription-quantitative polymerase chain reaction. CCK-8 assay, TUNEL staining, flow cytometry analysis, and Western blot analysis were performed to test the effects of HDAC4 and metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) on hESCs. RNA pull-down and luciferase reporter assays were performed to validate the relationship between genes. In this study, the characteristics of hESCs were sustained in serum-free medium during a process of propagation. HDAC4 knockdown suppressed hESCs viability and promoted hESCs apoptosis. HDAC4 was targeted by miR-498-3p in hESCs. MALAT1 bound with miR-498-3p in hESCs. HDAC4 expression was positively regulated by MALAT1 and negatively regulated by miR-498-3p in hESCs. HDAC4 upregulation countervailed the effects of MALAT1 silencing on hESCs proliferation, apoptosis, and decidualization of hESCs. Overall, MALAT1 facilitated the decidualization of hESCs via binding with miR-498-3p and upregulating HDAC4, which might provide a new direction for the maintenance of a successful pregnancy.

Wnt4, Wnt6 and β-catenin expression in human placental tissue - is there a link with first trimester miscarriage? Results from a pilot study

BACKGROUND

Demystifying the events around early pregnancy is challenging. A wide network of mediators and signaling cascades orchestrate the processes of implantation and trophoblast proliferation. Dysregulation of these pathways could be implicated in early pregnancy loss. There is accumulating evidence around the role of Wnt pathway in implantation and early pregnancy. The purpose of this study was to explore alterations in the expression of Wnt4, Wnt6 and β-catenin in placental tissue obtained from human first trimester euploid miscarriages versus normally developing early pregnancies.

METHODS

The study group consisted of first trimester miscarriages (early embryonic demises and incomplete miscarriages) and the control group of social terminations of pregnancy (TOPs). The placental mRNA expression of Wnt4, Wnt6 and β-catenin was studied using reverse transcription PCR and real time PCR. Only euploid conceptions were included in the analysis.

RESULTS

Wnt4 expression was significantly increased in placental tissue from first trimester miscarriages versus controls (p = 0.003). No significant difference was documented in the expression of Wnt6 (p = 0.286) and β-catenin (p = 0.793). There was a 5.1fold increase in Wnt4 expression for early embryonic demises versus TOPs and a 7.6fold increase for incomplete miscarriages versus TOPs - no significant difference between the two subgroups of miscarriage (p = 0.533).

CONCLUSIONS

This is, to our knowledge, the first study demonstrating significant alteration of Wnt4 expression in human placental tissue, from failed early pregnancies compared to normal controls. Undoubtedly, a more profound study is needed to confirm these preliminary findings and explore Wnt mediators as potential targets for strategies to predict and prevent miscarriage.

Dysregulated GLUT1 may be involved in the pathogenesis of preeclampsia by impairing decidualization

Preeclampsia (PE), a hypertensive complication in pregnancy, is a major contributor to maternal and fetal morbidity and mortality. PE has long been regarded a heterogeneous disorder with a pathogenesis that involves multiple genes and factors. Glucose transporter 1 (GLUT1) is a central rate-limiting pump that is involved in glucose uptake and subsequent utilization. Our previous RNA-seq results demonstrated GLUT1 was significantly downregulated in deciduas from patients with severe PE. Therefore, in this study, we aimed to explore the role of GLUT1 in the occurrence of PE. Our data showed that mRNA and protein levels of GLUT1 were significantly downregulated in the deciduas from patients with severe PE. Additionally, GLUT1 levels were substantially upregulated in human endometrial stromal cells (HESCs) during in vitro decidualization. Moreover, GLUT1 knockdown significantly reduced the mRNA levels of decidualization markers (IGFBP1 and PRL) and aerobic glycolysis-related genes (LDHA and MCT4), as well as decreased glucose uptake and lactate production. Furthermore, upon GLUT1 knockdown, the levels of apoptotic genes P53, P21, and BAX increased whereas the level of BCL2 decreased. Target prediction results and luciferase analysis showed that GLUT1 is one of the targets of miR-140-5p, which is partly responsible for downregulated GLUT1 levels. Collectively, these results demonstrate that GLUT1 exerts a pivotal role in human decidualization by participating in glycolysis, and that GLUT1 deficiency may trigger aberrant glycolysis, thereby leading to destructive decidualization that may impede blastocyst implantation, trophoblast invasion, and subsequent placental development, which are associated with PE. Taken together, these data suggest that GLUT1 might be a promising target for PE therapy.

Upregulation of circRNA hsa_circ_0008726 in Pre-eclampsia Inhibits Trophoblast Migration, Invasion, and EMT by Regulating miR-345-3p/RYBP Axis

Accumulating evidence shows that impaired spiral artery remodeling, placental dysfunction, and insufficient trophoblast infiltration contribute to the etiology and pathogenesis of pre-eclampsia (PE). circRNAs are a class of endogenous non-coding RNAs implicated in the pathogenesis of many diseases, including PE. This study aims to investigate the role of circRNA hsa_circ_0008726 in regulating the migration and invasion of extravillous trophoblast cells. RNase R assay was performed to confirm that circ_0008726 was a circular transcript. The expression of circ_0008726, RYBP, and miR-345-3p was examined by qRT-PCR. The functional interaction between miR-345-3p and circ_0008726 or RYBP was confirmed using dual-luciferase reporter assay and RNA immunoprecipitation (RIP). Cell migration and invasion ability was analyzed by Transwell assays. Western blot was used for the quantification of RYBP protein level. Circ_0008726 expression was significantly increased in PE placenta tissues as compared with normal placenta tissues. Circ_0008726 was resistant to RNase R digestion and was predominately located in the cytoplasm of HTR-8/SVneo cells. Silencing circ_0008726 promoted cell migration and EMT (epithelial-mesenchymal transition), while circ_0008726 overexpression suppressed these processes. Mechanistically, circ_0008726 sponged miR-345-3p to negatively regulate its expression, and miR-345-3p negatively modulated the expression of RYBP. In PE samples, the expression level of circ_0008726 was negatively correlated with miR-345-3p level, but was positively correlated with RYBP expression. Transfection of miR-345-3p mimic or RYBP knockdown counteracted the effects of circ_0008726 overexpression on cell migration and EMT. Our data demonstrate the upregulation of circ_0008726 in PE placenta, which inhibits the migration, invasion, and EMT of HTR-8/SVneo cells by targeting miR-345-3p/RYBP axis. These data suggest that circ_0008726 could be a potential biomarker and therapeutic target for PE.

Roles and action mechanisms of WNT4 in cell differentiation and human diseases: a review

WNT family member 4 (WNT4), which belongs to the conserved WNT protein family, plays an important role in the development and differentiation of many cell types during the embryonic development and adult homeostasis. Increasing evidence has shown that WNT4 is a special ligand that not only activates the β-catenin independent pathway but also acts on β-catenin signaling based on different cellular processes. This article is a summary of the current knowledge about the expression, regulation, and function of WNT4 ligands and their signal pathways in cell differentiation and human disease processes. WNT4 is a promoter in osteogenic differentiation in bone marrow stromal cells (BMSCs) by participating in bone homeostasis regulation in osteoporotic diseases. Non-canonical WNT4 signaling is necessary for metabolic maturation of pancreatic β-cell. WNT4 is also necessary for decidual cell differentiation and decidualization, which plays an important role in preeclampsia. WNT4 promotes neuronal differentiation of neural stem cell and dendritic cell (DC) into conventional type 1 DC (cDC1). Besides, WNT4 mediates myofibroblast differentiation in the skin, kidney, lung, and liver during scarring or fibrosis. On the negative side, WNT4 is highly expressed in cancer tissues, playing a pro-carcinogenic role in many cancer types. This review provides an overview of the progress in elucidating the role of WNT4 signaling pathway components in cell differentiation in adults, which may provide useful clues for the diagnosis, prevention, and therapy of human diseases.

Circular RNA hsa_circ_0026552 inhibits the proliferation, migration and invasion of trophoblast cells via the miR‑331‑3p/TGF‑βR1 axis in pre‑eclampsia

Globally, pre-eclampsia (PE) is a gestational disorder that causes increased morbidity of the fetus and mortality induced by pregnancy. Despite various studies, the understanding of the causes or mechanism of the development of PE remains elusive. Thus, the present study aimed to investigate the role of circular (circ)RNA hsa_circ_0026552 (hsa_circ_0026552) in the development of PE and its mechanism of regulation. hsa_circ_0026552 differential expression in PE tissue data and clinical samples were analyzed and it was observed that hsa_circ_0026552 is highly upregulated in PE samples. Furthermore, miR-331-3p was detected as an hsa_circ_0026552 target miRNA and TGF-βR1 gene as a target of miR-331-3p. These results were confirmed using various assays, including dual-luciferase reporter, reverse transcription-quantitative PCR and RNA pull-down assay. It was observed that miR-331-3p expression was negatively correlated to hsa_circ_0026552 relative expression, while TGF-βR1 expression was positively correlated to hsa_circ_0026552 expression evaluated by Pearson's correlation test. The functional experiments, including Cell Counting Kit-8, colony formation and Transwell assay, showed that silencing hsa_circ_0026552 could significantly strengthen the proliferation, migration and invasion of the trophoblastic HTR-8/SVneo cells, but the subsequent overexpression of hsa_circ_0026552 reversed this. Mechanistically, it was concluded that hsa_circ_0026552 acts as a miR-331-3p sponge to upregulate TGF-βR1 expression in trophoblasts and is involved significantly in PE development and progression in pregnant women. The circRNA hsa_circ_0026552 could be a novel therapeutic target and prognostic biomarker for PE.

Clinical consequences of defective decidualization

Decidualization is characterized by a series of genetic, metabolic, morphological, biochemical, vascular and immune changes occurring in the endometrial stroma in response to the implanting embryo or even before conception and involves the stromal cells of the endometrium. It is a fundamental reproductive event occurring in mammalian species with hemochorial placentation. A growing body of experimental and clinical evidence strongly suggests that defective or disrupted decidualization contributes to the establishment of an inappropriate maternal-fetal interface. This has relevant clinical consequences, ranging from recurrent implantation failure and recurrent pregnancy loss in early pregnancy to several significant complications of advanced gestation. Moreover, recent evidence indicates that selected diseases of the endometrium, such as chronic endometritis and endometriosis, can have a detrimental impact on the decidualization response in the endometrium and may help explain some aspects of the reduced reproductive outcome associated with these conditions. Further research efforts are needed to fully understand the biomolecular mechanisms ans events underlying an abnormal decidualization response. This will permit the development of new diagnostic and therapeutic strategies aimed to improve the likelihood of achieveing a successful pregnancy.

Dysfunction of Decidual Macrophages Is a Potential Risk Factor in the Occurrence of Preeclampsia

Preeclampsia is a multi-factorial and multi-genetic disorder that affects more than eight million mother and baby pairs each year. Currently, most of the attention to the pathogenesis of preeclampsia has been focused on placenta, but recent progresses suggest that excellent decidualization lays foundation for placentation and growth. Moreover, preeclampsia is associated with an imbalance in immunoregulatory mechanisms, however, how the immune regulatory system in the decidua affects preeclampsia is still unclear. In our study, after intersecting the genes of differentially expressed between preeclampsia and the control gotten by conventional expression profile analysis and the genes contained in the ligand receptor network, we found eight differentially expressed genes in a ligand-receptor relationship, and the eight genes have a characteristic: most of them participate in the interaction between decidual macrophages and other decidual immune cells. The results of single-cell sequencing of decidual cells further demonstrated that decidual macrophages affect the functions of other immune cells through export. As a result, abnormal gene expression affects the export function of decidual macrophages, which in turn affects the interaction of decidual macrophages with other immune cells, thereby destroying the original immune regulation mechanism, and ultimately leading to the occurrence of preeclampsia.

Energy deficiency caused by CTPS downregulation in decidua may contribute to pre-eclampsia by impairing decidualization

Pre-eclampsia (PE) is a pregnancy-related disorder that occurs after 20 weeks of gestation. It seriously affects the health of maternity and the fetus. However, the pathogenesis of PE is still unknown. Decidualization deficiency is considered a contributing factor to the development of PE. CTP synthetase (CTPS) which is the rate-limiting enzyme in the CTP de novo biosynthesis, is essential for nucleic acid synthesis and cellular energy metabolism, and often appears as cytoophidium in many cell types. Here, we found that the expression of CTPS was significantly downregulated in decidual tissues of patients with severe PE compared with healthy pregnant women. During in vitro decidualization, changes in CTPS were accompanied by opposite fluctuation of the AMPK signaling pathway. Moreover, the downregulation of CTPS by glutamine analogs or CTPS small interfering RNA inhibited the decidualization process and the AMPK signaling pathway. Investigating the underlying mechanism of action by co-immunoprecipitation coupled with mass spectrometry showed that CTPS interacted with ATP synthase (ATPS) and maintained the content of ATP on Day 3 of decidualization. However, when combined with mitochondrial stress protein STRESS-70 instead of ATPS, the concentration of ATP on Day 6 of induction was reduced. Corresponding to this, CTPS was mainly distributes in the cytoplasm on Day 3 of induction, while it appeared both in the cytoplasm and the nucleus on Day 6 in decidualized cells, which was similar to that in cells before induction. In summary, we believe that CTPS plays an important role in decidualization by participating in energy metabolism. Abnormal expression of CTPS in decidualization would lead to abnormal decidualization and consequently result in the occurrence of PE.

Integrative analysis provides multi-omics evidence for the pathogenesis of placenta percreta

Pernicious placenta previa with placenta percreta (PP) is a catastrophic condition during pregnancy. However, the underlying pathogenesis remains unclear. In the present study, the placental tissues of normal cases and PP tissues of pernicious placenta previa cases were collected to determine the expression profile of protein‐coding genes, miRNAs, and lncRNAs through sequencing. Weighted gene co‐expression network analysis (WGCNA), accompanied by miRNA target prediction and correlation analysis, were employed to select potential hub protein‐coding genes and lncRNAs. The expression levels of selected protein‐coding genes, Wnt5A and MAPK13, were determined by quantitative PCR and immunohistochemical staining, and lncRNA PTCHD1‐AS and PAPPA‐AS1 expression levels were determined by quantitative PCR and fluorescence in situ hybridization. The results indicated that 790 protein‐coding genes, 382 miRNAs, and 541 lncRNAs were dysregulated in PP tissues, compared with normal tissues. WGCNA identified coding genes in the module (ME) black and ME turquoise modules that may be involved in the pathogenesis of PP. The selected potential hub protein‐coding genes, Wnt5A and MAPK13, were down‐regulated in PP tissues, and their expression levels were positively correlated with the expression levels of PTCHD1‐AS and PAPPA‐AS1. Further analysis demonstrated that PTCHD1‐AS and PAPPA‐AS1 regulated Wnt5A and MAPK13 expression by interacting with specific miRNAs. Collectively, our results provided multi‐omics data to better understand the pathogenesis of PP and help identify predictive biomarkers and therapeutic targets for PP.

Circular RNA circ_0111277 attenuates human trophoblast cell invasion and migration by regulating miR-494/HTRA1/Notch-1 signal pathway in pre-eclampsia

Mounting evidence has revealed that impaired spiral artery remodeling, placental dysfunction, and inadequate trophoblast invasion are closely correlated with the etiology and pathogenesis of pre-eclampsia (PE). Moreover, defective trophoblast invasion may trigger poor maternal-fetal circulation and placental hypoxia, leading to PE. However, the detailed molecular pathology of PE remains unclear. Although circRNAs, as a new type of stable and abundant endogenous noncoding RNA, have been proven to be essential to the pathogenesis of various diseases, their role in PE requires further verification. In this context, it is necessary to unveil the roles of circRNAs in regulating the migration and invasion of extravillous trophoblasts. In this study, using quantitative real-time PCR, we confirmed that hsa_circ_0111277 was upregulated in PE placentas relative to the level in normal pregnancy placentas. In addition, positive correlations between hsa_circ_0111277 expression and PE-related factors (proteinuria level at 24 h and placental weight) were identified by Pearson's analysis based on the clinical data of 25 PE patients. Moreover, fluorescence in situ hybridization analysis illustrated that circ_0111277 was preferentially localized within the cytoplasm. Mechanistically, circ_0111277 sponged hsa-miR-494-3p in trophoblast cells to attenuate the latter's repression by regulating HTRA1/Notch-1 expression. In conclusion, trophoblast cell migration and invasion were shown to be promoted and modulated by the hsa_circ_0111277/miR-494-3p/HTRA1/Notch-1 axis, which provides useful insight for exploring a new therapeutic approach for PE.

Downregulated low-density lipoprotein receptor-related protein 6 induces the maldevelopment of extravillous trophoblast via Wnt/β-catenin signaling pathway

Preeclampsia (PE), a special type of hypertensive disorder complicating pregnancy (HDCP), is highly associated with the migratory and invasive capacity of extravillous trophoblasts (EVTs). Here, we aimed to study the functions of low-density lipoprotein receptor-related protein 6 (LRP6) in PE pathogenesis. A comparative analysis of cellular gene expressions between placenta tissues collected from PE patients and normal pregnant women showed that the expressions of LRP6, β-catenin and matrix metallopeptidases/TIMP metallopeptidase inhibitors (MMPs/TIMPs) ratio in placentas of PE patients were much lower than the normal. Then, we constructed and transfected LRP6 siRNA (siLRP6) and LRP6 overexpression vectors into HTR6/SVneo cells. On the contrary to siLRP6, LRP6 overexpression could significant enhance cell viability, and strengthen the abilities of cell migration and invasion. Importantly, the overexpression of LRP6 could induce the upregulation of MMP-2 and MMP-9 levels, and downregulation of TIMPs. The mRNA and protein levels of β-catenin, an intracellular signal transducer of Wnt signaling pathway, were significantly up-regulated under the effects of LRP6 overexpression. XAV939, a Wnt/β-catenin pathway inhibitor, was introduced to confirm the involvement of Wnt/β-catenin pathway in functions of LRP6. The results of cell viability detection showed that XAV939 could significantly inhibit the positive effects of LRP6 overexpression on cell viability. Taken together, low-expressed LRP6 may be responsible of lower migration and invasion of EVTs and subsequent PE, and the mechanisms show a highly association with Wnt/β-catenin pathway.

Neonatal exposure to a glyphosate-based herbicide alters uterine decidualization in rats

We investigated whether defective modulation of uterine signaling may cause decidualization failure in rats neonatally exposed to a glyphosate-based herbicide (GBH). Female pups received vehicle or 2mg/kg of GBH from postnatal day (PND) 1 to PND7. On PND8 and PND21, Wnt5a and β-catenin expression was evaluated in uterine samples. On gestational day (GD) 9, Wnt5a, Wnt7a and β-catenin expression and Dkk1 and sFRP4 mRNA were evaluated on implantation sites. On PND8, GBH-exposed rats showed increased Wnt5a and β-catenin expression in luminal epithelium (LE), whereas on PND21, they showed increased Wnt5a and β-catenin expression in subepithelial stroma but decreased β-catenin expression in glandular epithelium. On GD9, GBH-exposed rats showed decreased Wnt5a and Wnt7a expression in the antimesometrial zone and LE respectively, without changes in β-catenin expression, while Dkk1 and sFRP4 were up- and down-regulated respectively. We concluded that neonatal GBH exposure may lead to embryo losses by disturbing uterine signaling.