Non-Coding RNAs in Preeclampsia-Molecular Mechanisms and Diagnostic Potential

Circ_0008440 Inhibits Proliferation and Promotes Apoptosis of Trophoblast Cells through the miR-194-5p/PFKFB2 Axis

Preeclampsia (PE), an idiopathic hypertensive disorder that arises during pregnancy, poses a serious threat to the health of expectant mothers. Human chorionic trophoblast cells (HTR-8/SVneo) are associated with the development of PE. It has been reported that circ_0008440 expression is abnormally increased in the placental tissues of PE patients. However, the function of circ_0008440 within HTR-8/SVneo cells during PE has yet to be fully elucidated. The study used RT-qPCR and western blot assay to evaluate the expression levels of 6-Phosphofructo-2-Kinase/Fructose-2,6-Biphosphatase 2 (PFKFB2), circ_0008440, and miR-942-5p in PE patients. Cells viability was measured using cell counting kit-8 (CCK-8) assay. Cell cycle assay and 5-ethynyl-2'-deoxyuridine (EDU) assay were used to measure cell proliferation. Cell apoptosis was assessed using flow cytometry assay. Western blot assay was used to detect protein expression. Dual-luciferase reporter assay and RNA pull-down assay were used to assess the interactions among circ_0008440, miR-942-5p, and PFKFB2 in HTR-8/SVneo cells. The study showed that the expression levels of circ_0008440 and PFKFB2 were significantly increased, while the expression of miR-942-5p was significantly decreased in the placental tissues of PE patients. Silencing of circ_0008440 promoted proliferation and tube formation and inhibited apoptosis of HTR-8/SVneo cells. In terms of molecular mechanism, miR-942-5p inhibitor or overexpression of PFKFB2 could partially reverse the effects of circ_0008440 silencing on the biological characteristics of HTR-8/SVneo cells. Collectively, circ_0008440 could act as a sponge of miR-942-5p to regulate the expression of PFKFB2, which further inhibited viability and proliferation of HTR-8/SVneo cells and promoted cell apoptosis.

Urinary miRNA Expression in Pre-Eclampsia During Early and Mid-Pregnancy

Background: Pre-eclampsia (PE) is a serious condition affecting 2-8% of pregnancies worldwide, leading to high maternal and fetal morbidity and mortality. MicroRNAs (miRNAs), small non-coding RNA molecules, have emerged as potential biomarkers for various pregnancy-related pathologies, including PE. MiRNAs in plasma and serum have been extensively studied, but urinary miRNAs remain underexplored, especially during early pregnancy. This study aimed to investigate the urinary miRNA expression profiles in women with pre-eclampsia during the first and second trimesters. Materials and Methods: A prospective study was conducted using 48 urine samples from 24 pregnant women (n = 12 pre-eclampsia and n = 12 controls). Urine samples were collected in the first (9-13 weeks) and second (22-24 weeks) trimesters. MiRNA isolation, library preparation, and high-throughput sequencing were performed, followed by differential expression and enrichment analyses. Results: In the first trimester, five miRNAs were dysregulated in PE in comparison with the control group (hsa-miR-184, hsa-miR-203a-3p, hsa-miR-205-5p, hsa-miR-223-3p-downregulated; hsa-miR-1-3p-upregulated). In the second trimester, hsa-miR-205-5p and hsa-miR-223-3p were downregulated, and hsa-miR-9-5p, hsa-miR-1-3p, and hsa-miR-206 were upregulated. Conclusions: Our study identified differentially expressed miRNAs in the urine of pre-eclamptic patients during early pregnancy. These findings suggest that specific urinary miRNAs could serve as non-invasive biomarkers for the early detection and risk assessment of pre-eclampsia. The changes in the level of differential expression of miRNAs during gestation highlight their role in the progression of PE. Further research and validation with a larger cohort are needed to explore their clinical potential for improving maternal and fetal outcomes through early intervention.

Serum lncRNAs TUG1, H19, and NEAT1 and their target miR-29b/SLC3A1 axis as possible biomarkers of preeclampsia: Potential clinical insights

To date, the epigenetic signature of preeclampsia (PE) is not completely deciphered. Oxidative stress-responsive long non-coding RNAs (lncRNAs) are deregulated in preeclamptic placenta; however, their circulating profiles and diagnostic abilities are still unexplored. We investigated serum redox-sensitive lncRNAs TUG1, H19, and NEAT1, and their target miR-29b/cystine/neutral/dibasic amino acids transporter solute carrier family 3, member 1 (SLC3A1) as potential non-invasive biomarkers of PE risk, onset, and severity. We recruited 82 patients with PE and 78 healthy pregnant women. We classified PE patients into early-onset (EOPE) and late-onset (LOPE) subgroups at a cut-off 34 gestational weeks and into severe and mild PE subgroups by blood pressure and proteinuria criteria. Bioinformatics analysis was employed to select lncRNAs/microRNA/target gene interactions. Serum H19, NEAT1, and SLC3A1 mRNA expression were reduced, meanwhile miR-29b levels were elevated, whereas there was no significant difference in TUG1 levels between PE patients and healthy pregnancies. Serum H19 levels were lower, whereas miR-29b levels were higher in EOPE versus LOPE. Serum miR-29b and H19 levels were higher in severe versus mild PE. ROC analysis identified serum H19, NEAT1, miR-29b, and SLC3A1 as potential diagnostic markers, with H19 (AUC = 0.818, 95%CI = 0.744-0.894) and miR-29b (AUC = 0.82, 95%CI = 0.755-0.885) were superior discriminators. Only H19 and miR-29b discriminated EOPE and severe PE cases. In multivariate logistic analysis, miR-29b and H19 were associated with EOPE, using maternal age and gestational age as covariates, while miR-29b was associated with severe PE, using maternal age as covariate. Studied markers were correlated with clinical and ultrasound data in the overall PE group. Serum H19 and TUG1 were negatively correlated with albuminuria in EOPE and LOPE, respectively. NEAT1 and SLC3A1 were correlated with ultrasound data in EOPE. Likewise, TUG1, miR-29b, and SLC3A1 showed significant correlations with ultrasound data in LOPE. Conclusively, this study configures SLC3A1 expression as a novel potential serum biomarker of PE and advocates serum H19 and miR-29b as biomarkers of EOPE and miR-29b as a biomarker of PE severity.

The Hidden Relationship between Intestinal Microbiota and Immunological Modifications in Preeclampsia Pathogenesis

Preeclampsia is a multifactorial gestational syndrome characterized by increased blood pressure during pregnancy associated with multiorgan involvement. The impact of this disease on maternal and neonatal health is significant, as it can lead to various fetal comorbidities and contribute to the development of maternal comorbidities later in life. Consistent evidence has shown that the microbiota acts as a regulator of the immune system, and it may, therefore, influence the development of preeclampsia by modulating immune factors. This narrative review aims to investigate the role of the immune system in the pathogenesis of preeclampsia and to summarize the most recent literature on the possible link between preeclampsia and alterations in the intestinal microbiota. To this end, we conducted a literature search, aiming to perform a narrative review, on PubMed and Embase from January 1990 to March 2024, focusing on the latest studies that highlight the main differences in microbial composition between patients with and without preeclampsia, as well as the effects of microbial metabolites on the immune system. From the review of 28 studies assessing the intestinal microbiota in preeclamptic women, preeclampsia could be associated with a state of dysbiosis. Moreover, these patients showed higher plasmatic levels of endotoxin, pro-inflammatory cytokines, and T helper 17 cells; however, the findings on specific microbes and metabolites that could cause immune imbalances in preeclampsia are still preliminary.

Circulating extracellular vesicular microRNA signatures in early gestation show an association with subsequent clinical features of pre-eclampsia

In a prospective cohort of subjects who subsequently developed preeclampsia (PE, n = 14) versus remaining healthy (NORM, n = 12), early gestation circulating extracellular vesicles (EVs) containing a panel of microRNA signatures were characterized and their biological networks of targets deciphered. Multiple microRNAs of which some arose from the placenta (19MC and 14MC) demonstrated changes in association with advancing gestation, while others expressed were pathognomonic of the subsequent development of characteristic clinical features of PE which set in as a late-onset subtype. This panel of miRNAs demonstrated a predictability with an area under the curve of 0.96 using leave-one-out cross-validation training in a logistic regression model with elastic-net regularization and precautions against overfitting. In addition, this panel of miRNAs, some of which were previously detected in either placental tissue or as maternal cell-free non-coding transcripts, lent further validation to our EV studies and the observed association with PE. Further, the identified biological networks of targets of these detected miRNAs revealed biological functions related to vascular remodeling, cellular proliferation, growth, VEGF, EGF and the PIP3/Akt signaling pathways, all mediating key cellular functions. We conclude that we have demonstrated a proof-of-principle by detecting a panel of EV packaged miRNAs in the maternal circulation early in gestation with possibilities of biological function in the placenta and other maternal tissues, along with the probability of predicting the subsequent clinical appearance of PE, particularly the late-onset subtype.

The crosstalk between cell death and pregnancy related diseases: A narrative review

Programmed cell death is intricately linked to various physiological phenomena such as growth, development, and metabolism, as well as the proper function of the pancreatic β cell and the migration and invasion of trophoblast cells in the placenta during pregnancy. Traditional and recently identified programmed cell death include apoptosis, autophagy, pyroptosis, necroptosis, and ferroptosis. In addition to cancer and degenerative diseases, abnormal activation of cell death has also been implicated in pregnancy related diseases like preeclampsia, gestational diabetes mellitus, intrahepatic cholestasis of pregnancy, fetal growth restriction, and recurrent miscarriage. Excessive or insufficient cell death and pregnancy related diseases may be mutually determined, ultimately resulting in adverse pregnancy outcomes. In this review, we systematically describe the characteristics and mechanisms underlying several types of cell death and their roles in pregnancy related diseases. Moreover, we discuss potential therapeutic strategies that target cell death signaling pathways for pregnancy related diseases, hoping that more meaningful treatments will be applied in clinical practice in the future.

CircPAPPA2 plays a role in preeclampsia pathogenesis via regulation of the miR-942/miR-5006-3p

CircRNAs are a class of endogenous non-coding RNAs implicated in the pathogenesis of many pregnancy related diseases, one of which is pre-eclampsia (PE). This study aims to investigate the role of CircPAPPA2 (circbase ID: hsa_circ_0015382) in regulating the migration and invasion of trophoblast cells. RNA sequencing was used to identify the differentially expressed circRNAs in placenta of PE and normal pregnant women. Quantitative polymerase chain reaction (qRT-PCR) was used to verify the expression of circPAPPA2 and two miRNAs (miR-942-5p, 5006-3p) in placenta of PE and normal pregnant women. CCK8 and transwell experiments were performed to assess the function of circPAPPA2 in PE development.The interaction between circPAPPA2 and miR-942-5p/miR-5006-3p was verified by dual-luciferase reporter assay. Finally, bioinformatics analyzed with gene ontology, Kyoto Encyclopedia of the target genes. The results showed that the expression of circPAPPA2 was increased in placenta of PE pregnant women. Also, circPAPPA2 impedes trophoblasts cell proliferation and invasion. Moreover, the expression of circPAPPA2 was positively correlated with systolic blood pressure and urine protein. In addition, circPAPPA2 serves as a sponge of miR-942-5p and miR-5006-3p. In conclusion, CircPAPPA2 regulates trophoblasts cell proliferation and invasion by mediating the miR-942/miR-5006-3p.

Unveiling immune tolerance pathways in preeclampsia placenta: implications for molecular targets and discovery of potential biomarkers

During pregnancy, there is a link between disruption of maternal immune tolerance and preeclampsia, but the molecular mechanisms that regulate maternal and fetal immune tolerance remain unclear. This study employs bioinformatics to identify new markers related to placental immune tolerance and explore their potential role in predicting preeclampsia. Analyzing preeclampsia-related gene expression profiles in the Gene Expression Omnibus (GEO) dataset reveals 211 differentially expressed genes (DEGs) in the placenta, mainly influencing immune cell differentiation and response pathways. Employing weighted gene co-expression network analysis (WGCNA) and lasso regression, four potential target genes (ANKRD37, CRH, LEP, SIGLEC6) are identified for potential prediction of preeclampsia. Validation using the GSE4707 dataset confirmed the diagnostic and predictive potential of these candidate genes. RT-qPCR verified up-regulation in the placenta, while ELISA showed their correlation with immune tolerance factors associated with placental immune tolerance. As a result of this study, identifies potential biomarkers associated with placental immunity and contributes to understanding the molecular mechanism of preeclampsia.

Model construction and application for predicting pre-eclampsia by Sonoclot coagulation analyzer

Maternal age has significantly increased among Chinese women, thereby posing risk of pregnancy-related complications. Preeclampsia is a leading cause of maternal and perinatal morbidity and mortality, and coagulation analysis in conjunction with clinical signs and symptoms are generally used for its diagnosis with limited efficacy. Sonoclot coagulation analyzer is effective in assessing coagulation function used during cerebral surgery and cardiovascular surgery. However, its use has not been explored in preeclampsia. Here, we investigated the potential use of Sonoclot in diagnosing preeclampsia in obstetrics cases. Subjects meeting the screening criteria were divided either into a test group or a control group, according to whether they were preeclamptic or not. We recorded the Sonoclot-derived coagulation and the routine coagulation parameters including platelet function (PF), activated clotting time (ACT) and clot rate (CR), prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), fibrinogen (FIB), and platelet count. Regression analysis was done on the relevant parameters to assess the feasibility of Sonoclot analyzer in preeclampsia diagnosis. In parallel, changes in preeclampsia lncRNAs was also evaluated. Significant differences were recorded in PT and ACT between the two groups. In the monovariant logistic regression, PT and ACT appeared to be reliable predictor variables. In the multinomial logistic regression, a total of five regression steps were performed with decreasing AIC values. The K-fold cross validation resulted in an accuracy rate (ACC) of 77.5%, a false positive rate of 16.4%, and a false negative rate of 33.2%. lncRNAs ANRIL and HOXD-AS1 were found deregulated. Our findings indicate that Sonoclot may be useful for diagnosis of preeclampsia in obstetrics.

Oxidative stress contributes to hypermethylation of Histone H3 lysine 9 in placental trophoblasts from preeclamptic pregnancies

Background and objective

Aberrant epigenetic regulation and increased oxidative stress in the placenta play a significant role in placental pathophysiology and fetal programming in preeclampsia, a hypertensive disorder in human pregnancy. The purpose of the study is to investigate if hypermethylation of histone H3K9 occurs in placental trophoblasts from preeclampsia.

Methods

Trophoblasts were isolated and cultured from 14 placentas, 7 from normotensive pregnant women and 7 from preeclamptic pregnancies. Methylated H3K9 expression and antioxidant superoxide dismutase expression were determined by Western blot. We also examined consequences of oxidative stress and the downstream effects of histone methyltransferase inhibition on H3K9 expression associated with antioxidant CuZn-SOD and Mn-SOD expression in placental trophoblasts.

Results

We found that expression of mono-, di-, and tri-methylation of histone H3 lysine 9 (H3K9me1, H3K9me2 and H3K9me3) was significantly increased, p<0.01, which correlated with downregulation of antioxidant superoxide dismutase CuZn-SOD and Mn-SOD expression, in trophoblasts from preeclamptic placentas compared to those from uncomplicated control placentas. We further demonstrated hypoxia could promote histone H3K9 methylation in placental trophoblasts, and hypoxia-induced upregulation of H3K9me1, H3K9me2 and H3K9me3 expression was reversible when hypoxic condition was removed. In addition, we also uncovered that inhibition of methyltransferase not only prevented hypoxia-induced upregulation of H3K9me1, H3K9me2 and H3K9me3 expression, but also abolished hypoxia-induced downregulation of CuZn-SOD and Mn-SOD expression in placental trophoblasts.

Conclusions

These findings are noteworthy and provide further evidence that increased oxidative stress in the intrauterine environment is likely a mechanism to induce aberrant histone modification in placental trophoblasts in preeclampsia. Moreover, CuZn-SOD and Mn-SOD expression/activity are possibly H3K9 methylation-dependent in placental trophoblasts, which further suggest that oxidative stress and aberrant histone modification have significant impact on placental trophoblasts/fetal programming in preeclampsia.

The Pathophysiological, Genetic, and Hormonal Changes in Preeclampsia: A Systematic Review of the Molecular Mechanisms

Preeclampsia, a serious complication of pregnancy, involves intricate molecular and cellular mechanisms. Fetal microchimerism, where fetal cells persist within maternal tissues and in circulation, acts as a mechanistic link between placental dysfunction and maternal complications in the two-stage model of preeclampsia. Hormones, complements, and cytokines play pivotal roles in the pathophysiology, influencing immune responses, arterial remodeling, and endothelial function. Also, soluble HLA-G, involved in maternal-fetal immune tolerance, is reduced in preeclampsia. Hypoxia-inducible factor 1-alpha (Hif-α) dysregulation leads to placental abnormalities and preeclampsia-like symptoms. Alterations in matrix metalloproteinases (MMPs), endothelins (ETs), chemokines, and cytokines contribute to defective trophoblast invasion, endothelial dysfunction, and inflammation. Preeclampsia's genetic complexity includes circRNAs, miRNAs, and lncRNAs. CircRNA_06354 is linked to early-onset preeclampsia by influencing trophoblast invasion via the hsa-miR-92a-3p/VEGF-A pathway. The dysregulation of C19MC, especially miR-519d and miR-517-5p, affects trophoblast function. Additionally, lncRNAs like IGFBP1 and EGFR-AS1, along with protein-coding genes, impact trophoblast regulation and angiogenesis, influencing both preeclampsia and fetal growth. Besides aberrations in CD31+ cells, other potential biomarkers such as MMPs, soluble HLA-G, and hCG hold promise for predicting preeclampsia and its complications. Therapeutic interventions targeting factors such as peroxisome PPAR-γ and endothelin receptors show potential in mitigating preeclampsia-related complications. In conclusion, preeclampsia is a complex disorder with a multifactorial etiology and pathogenesis. Fetal microchimerism, hormones, complements, and cytokines contribute to placental and endothelial dysfunction with inflammation. Identifying novel biomarkers and therapeutic targets offers promise for early diagnosis and effective management, ultimately reducing maternal and fetal morbidity and mortality. However, further research is warranted to translate these findings into clinical practice and enhance outcomes for at-risk women.

Expression of miRNAs and proinflammatory cytokines in pregnant women with gestational diabetes mellitus

Altered microRNAs (miRNAs1) and cytokines expression levels are associated with several pregnancy-induced complications. We evaluated the profile of circulating miRNAs (miR-17, miR-29a and miR-181a) and proinflammatory cytokines (TNF-α, IL-1β, IL-6 and IL-17) in women with gestational diabetes mellitus (GDM2), as well as their potential use as GDM biomarkers. The case-control study included 65 pregnant women divided into 2 groups - GDM and control. Expression levels of miRNAs in plasma samples and cytokines mRNA isolated from peripheral blood buffy coat were analyzed by quantitative real-time PCR (qPCR3). Significant miR-29a downregulation was found in GDM compared to the control group, and was even more significant after adjustments for covariates. miR-17 and miR-181a expression levels did not differ between the examined groups. Expression levels of IL-1β were significantly higher in GDM group compared to controls, while TNF-α, IL-6 and IL-17 did not show significant changes in expression between the two groups. As jugded from the ROC curve analysis, miR-29a and IL-1β had a significant capacity to discriminate between CG and GDM. Additionally, a positive correlation was established between IL-1β and TNF-α in the GDM group. GDM appeared to be associated with altered levels of miR-29a and IL-1β making them markers of this condition.

Exosomal small RNA profiling in first-trimester maternal blood explores early molecular pathways of preterm preeclampsia

Introduction

Preeclampsia (PE) is a severe obstetrical syndrome characterized by new-onset hypertension and proteinuria and it is often associated with fetal intrauterine growth restriction (IUGR). PE leads to long-term health complications, so early diagnosis would be crucial for timely prevention. There are multiple etiologies and subtypes of PE, and this heterogeneity has hindered accurate identification in the presymptomatic phase. Recent investigations have pointed to the potential role of small regulatory RNAs in PE, and these species, which travel in extracellular vesicles (EVs) in the circulation, have raised the possibility of non-invasive diagnostics. The aim of this study was to investigate the behavior of exosomal regulatory small RNAs in the most severe subtype of PE with IUGR.

Methods

We isolated exosomal EVs from first-trimester peripheral blood plasma samples of women who later developed preterm PE with IUGR (n=6) and gestational age-matched healthy controls (n=14). The small RNA content of EVs and their differential expression were determined by next-generation sequencing and further validated by quantitative real-time PCR. We also applied the rigorous exceRpt bioinformatics pipeline for small RNA identification, followed by target verification and Gene Ontology analysis.

Results

Overall, >2700 small RNAs were identified in all samples and, of interest, the majority belonged to the RNA interference (RNAi) pathways. Among the RNAi species, 16 differentially expressed microRNAs were up-regulated in PE, whereas up-regulated and down-regulated members were equally found among the six identified Piwi-associated RNAs. Gene ontology analysis of the predicted small RNA targets showed enrichment of genes in pathways related to immune processes involved in decidualization, placentation and embryonic development, indicating that dysregulation of the induced small RNAs is connected to the impairment of immune pathways in preeclampsia development. Finally, the subsequent validation experiments revealed that the hsa_piR_016658 piRNA is a promising biomarker candidate for preterm PE associated with IUGR.

Discussion

Our rigorously designed study in a homogeneous group of patients unraveled small RNAs in circulating maternal exosomes that act on physiological pathways dysregulated in preterm PE with IUGR. Therefore, our small RNA hits are not only suitable biomarker candidates, but the revealed biological pathways may further inform us about the complex pathology of this severe PE subtype.

Hsa_circ_0001326 inhibited the proliferation, migration, and invasion of trophoblast cells via miR-145-5p/TGFB2 axis

PROBLEM

Preeclampsia (PE) is an obstetric disease involving multiple systems, which account for maternal and fetal complications and increased mortality. Circular RNAs (circRNAs) were recently deemed to associate with the pathogenesis of PE. This study aims to clarify the correlation between circRNA hsa_circ_0001326 and PE and explore its biological function in PE.

METHOD OF STUDY

The expression of hsa_circ_0001326 in PE placentas was detected by real-time quantitative PCR (qRT-PCR). After overexpressing or inhibiting hsa_circ_0001326 in trophoblast cells, the cell growth, migration, and invasion were evaluated by Cell Counting Kit-8 (CCK-8) and transwell assays. Western blot assay was applied to detect the epithelial-mesenchymal transition (EMT) proteins, E-cadherin and Vimentin. Furthermore, a dual-luciferase reporter assay was applied to verify the binding sites of hsa_circ_0001326, miR-145-5p, and transforming growth factor beta 2 (TGFB2).

RESULTS

Hsa_circ_0001326 was found to be higher expressed in PE placentas than in normal placentas. Furthermore, hsa_circ_0001326 played a negative regulating role in trophoblast cell viability, migration, and invasion. Overexpression of hsa_circ_0001326 inhibited the viability, migration, and invasion of trophoblast cells, while inhibition of hsa_circ_0001326 showed opposite effects. Mechanistically, hsa_circ_0001326 sponged miR-145-5p to elevate TGFB2 expression in trophoblast cells.

CONCLUSION

This study provided evidence that the up-regulated hsa_circ_0001326 in PE restrained trophoblast cells proliferation, migration, and invasion by sponging miR-145-5p to elevate TGFB2 expression. Our results might provide a novel insight into the role of hsa_circ_0001326 in the pathogenesis of PE.

Identification of LncRNA-miRNA-mRNA ceRNA network in hypoxia-induced HTR-8/SVneo cells for preeclampsia

Preeclampsia (PE) is a common pregnancy complication, and placental hypoxia is one of its causes. We aimed to identify the transcriptional profile and construct a long non-coding RNAs (lncRNA)-centered competing endogenous RNAs (ceRNA) network in hypoxia-induced HTR8/SVneo cells. We used datasets from the GEO database to identify important pathways in PE. We performed microarray profiling and functional analysis to identify differentially expressed long non-coding RNAs (lncRNAs), differentially expressed profiles of microRNA (miRNAs), and differentially expressed profiles of messenger RNA (mRNAs) in hypoxia-induced HTR8/SVneo cells. The candidates were validated using quantitative reverse transcription polymerase chain reaction. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes analyses were performed to understand the functional significance of differentially expressed genes. Finally, we constructed an lncRNA-centered ceRNA network. Several hub genes were validated both in placentas from PE and normal pregnancy, and in hypoxia-induced HTR8/SVneo cells. The hypoxic response pathway was involved in the pathophysiology of PE. Subsequently, we identified 536 differentially expressed profiles of lncRNAs (183 upregulated and 353 downregulated), 46 differentially expressed profiles of miRNAs (35 upregulated and 11 downregulated), and 2782 differentially expressed profiles of mRNAs (DEmRNAs) (1031 upregulated and 1751 downregulated) in hypoxia-induced HTR8/SVneo cells. Gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses revealed potential pathways affected by these genes, such as angiogenesis, the HIF-1 signaling pathway, and the PI3K-Akt signaling pathway. The ceRNA network comprised 35 lncRNAs, 11 miRNAs, 27 mRNAs, and 2 hub lncRNAs, which might play a vital role in placental functions and PE. Our results revealed the transcriptome profile and constructed an lncRNA-centered ceRNA network in hypoxia-induced HTR8/SVneo cells, thereby providing potential therapeutic targets for PE.

Placental pathology of preeclampsia from a clinical point of view: Correlation between placental histopathology, clinical signs of preeclampsia and neonatal outcome

AIM

To evaluate the associations between placental histopathology (signs of maternal and fetal vascular malperfusion, delayed villous maturation, villitis of unknown etiology) and subtypes of preeclampsia by onset, clinical aspects of the disease and neonatal outcome.

METHODS

Placental slides from preeclamptic pregnancies were retrospectively reviewed according to a uniform scheme. Information regarding obstetrical anamnesis, clinical data and perinatal outcome was collected from charts, and statistical analysis was performed in order to demonstrate associations between microscopic placental alterations and different aspects of preeclampsia.

RESULTS

A total of 49 cases were studied. Diffuse signs of maternal vascular malperfusion and avascular villi were more common in early-onset-preeclampsia associated with worse prognosis. Preeclampsia with fetal growth restriction had more often diffuse signs of maternal and fetal vascular malperfusion and villitis of unknown etiology. Recurring preeclampsia was associated with more common perivasculitis. Umbilical and uterine artery Doppler indices were associated with medial hypertrophy and/or acute atherosis of maternal decidual vessels. Large foci of avascular villi correlated with extent of maternal 24-h-proteinuria which itself correlated with outcome of preeclampsia. Rate of capillarisation of villi was significantly lower in case of hypertension requiring a three-drug combination of antihypertensive medications versus hypertension treated with one or two drugs, preeclampsia with growth restriction, and stillbirth versus live birth.

CONCLUSIONS

Early- versus late-onset-preeclampsia showed a markedly different profile of histopathological features and perinatal outcome, reflecting their distinguished pathogenesis and prognosis; preeclampsia complicated with fetal growth restriction also had distinctive features. Qualitative and quantitative changes define placental pathology of preeclampsia.

Circ_0111277 suppresses trophoblast cell proliferation, angiogenesis, migration, invasion and EMT via regulating miR-188-3p/GRHL2 axis

PROBLEM

Preeclampsia (PE) is the main factor threatening the life of primipara. Defective migration and invasion of trophoblast cells was one of the causes of PE. Circ_0111277 had been reported to be related to the development of PE, but the mechanism of its effect on trophoblast cells needed further study.

METHOD OF STUDY

The expression of circ_0111277, microRNA-188-3p (miR-188-3p) and grainyhead-like 2 (GRHL2) mRNA were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Cell Counting Kit-8 (CCK-8) assay, 5-Ethynyl-20-deoxyuridine (EdU) and colony formation assay were used to examine cell proliferation ability. Tube formation and transwell assay were performed to assess the angiogenesis and metastasis ability of cells. Western blot was applied to measure the levels of epithelial-mesenchymal transition (EMT)-related proteins (E-cadherin and Vimentin) and GRHL2 protein. The relationship between miR-188-3p and circ_0111277 or GRHL2 was verified by the dual luciferase reporter experiment.

RESULTS

Circ_0111277 and GRHL2 were elevated, and miR-188-3p was declined in PE patients. Overexpression of circ_0111277 could inhibit the proliferation, angiogenesis, migration, invasion and EMT of trophoblast cells (HTR-8/Svneo). Circ_0111277 was the molecular sponge of miR-188-3p. MiR-188-3p up-regulation could reduce the inhibition of HTR-8/Svneo cell growth caused by overexpression of circ_0111277. GRHL2 was a target gene of miR-188-3p, and GRHL2 silencing relieved the adverse effects of miR-188-3p inhibitors on HTR-8/Svneo. In general, circ_0111277 up-regulated GRHL2 expression through sponge miR-188-3p.

CONCLUSION

Highly expressed circ_0111277 up-regulated the expression of GRHL2 through sponge miR-188-3p, thereby inhibiting trophoblast cells function, which suggested a new molecular mechanism for the pathogenesis of PE.

Molecular Mechanisms of Pregnancy-Related Vascular Remodeling and Pregnancy Complications

The purpose of this editorial is to highlight the various observations made in this Special Issue in the International Journal of Molecular Sciences [...].

IGF2BP2 enhances LincRNA01116 stability via m6 A: A potential biomarker and therapeutic target for patients with pre-eclampsia

Pre-eclampsia (PE) is a serious complication in pregnant women characterized by failure of placental remodeling and is one of the primary causes of changes in the placental structure and function. The aberrant expression of long noncoding RNA is associated with the occurrence and progression of PE. This study found that linc01116 expression was significantly downregulated in PE patients and was related to poor uterine spiral artery remodeling. Knockdown of linc01116 remarkably decreased the angiogenesis of trophoblast cells in vitro and in vivo. Mechanistically, IGF2BP2 regulated linc01116 RNA stability via m⁶ A methylation. Bioinformatics and other experiments further revealed that linc01116 upregulates AAMP expression by adsorbing miR-210-3p in trophoblast cells. In conclusion, this study revealed the critical role of linc01116 in regulating trophoblast angiogenesis. Furthermore, the study provides new clues for detecting placental pathology in PE.

Interaction between Long Noncoding RNAs and Syncytin-1/Syncytin-2 Genes and Transcripts: How Noncoding RNAs May Affect Pregnancy in Patients with Systemic Lupus Erythematosus

BACKGROUND

Patients with systemic lupus erythematosus (SLE) often suffer from obstetric complications not necessarily associated with the antiphospholipid syndrome. These events may potentially result from the reduced placental synthesis of the fusogenic proteins syncytin-1 and syncytin-2, observed in women with pregnancy-related disorders. SLE patients have an aberrant noncoding (nc)RNA signature that may in turn dysregulate the expression of syncytin-1 and syncytin-2 during placentation. The aim of this research is to computationally evaluate and characterize the interaction between syncytin-1 and syncytin-2 genes and human ncRNAs and to discuss the potential implications for SLE pregnancy adverse outcomes.

METHODS

The FASTA sequences of the syncytin-1 and syncytin-2 genes were used as inputs to the Ensembl.org library to find any alignments with human ncRNA genes and their transcripts, which were characterized for their tissue expression, regulatory activity on adjacent genes, biological pathways, and potential association with human disease.

RESULTS

BLASTN analysis revealed a total of 100 hits with human long ncRNAs (lncRNAs) for the syncytin-1 and syncytin-2 genes, with median alignment scores of 151 and 66.7, respectively. Only lncRNAs TP53TG1, TTTY14, and ENSG00000273328 were reported to be expressed in placental tissue. Dysregulated expression of lncRNAs TP53TG1, LINC01239, and LINC01320 found in this analysis has previously been described in SLE patients as well as in women with a high-risk pregnancy. In addition, some of the genes adjacent to lncRNAs aligned with syncytin-1 or syncytin-2 in a regulatory region might increase the risk of pregnancy complications or SLE.

CONCLUSIONS

This is the first computational study showing alignments between syncytin-1 and syncytin-2 genes and human lncRNAs. Whether this mechanism affects syncytiotrophoblast morphogenesis in SLE females is unknown and requires further investigation.

Non-Coding RNAs in Airway Diseases: A Brief Overview of Recent Data

Inflammation of the human lung is mediated in response to different stimuli (e.g., physical, radioactive, infective, pro-allergenic, or toxic) such as cigarette smoke and environmental pollutants. These stimuli often promote an increase in different inflammatory activities in the airways, manifesting themselves as chronic diseases (e.g., allergic airway diseases, asthma chronic bronchitis/chronic obstructive pulmonary disease, or even lung cancer). Non-coding RNA (ncRNAs) are single-stranded RNA molecules of few nucleotides that regulate the gene expression involved in many cellular processes. ncRNA are molecules typically involved in the reduction of translation and stability of the genes of mRNAs s. They regulate many biological aspects such as cellular growth, proliferation, differentiation, regulation of cell cycle, aging, apoptosis, metabolism, and neuronal patterning, and influence a wide range of biologic processes essential for the maintenance of cellular homeostasis. The relevance of ncRNAs in the pathogenetic mechanisms of respiratory diseases has been widely established and in the last decade many papers were published. However, once their importance is established in pathogenetic mechanisms, it becomes important to further deepen the research in this direction. In this review we describe several of most recent knowledge concerning ncRNA (overall miRNAs) expression and activities in the lung.

Role of microRNAs regulating trophoblast cell function in the pathogenesis of pre‑eclampsia (Review)

Pre-eclampsia (PE) is a complicated pregnancy-specific disease and is considered the primary reason for maternal and foetal mortality and morbidity. PE has a multifactorial pathogenesis but the causes of PE remain unclear. The functions of trophoblasts, including differentiation, proliferation, migration, invasion and apoptosis, are essential for successful pregnancy. During the early stages of placental development, trophoblasts are strictly regulated by several molecular pathways; however, an imbalance of these molecular pathways can lead to severe placental lesions and pregnancy complications. Certain microRNAs (miRs) are abnormally expressed in PE, with several miRs involved in the regulation of pregnancy-associated genes. The present review discusses the miRs regulating trophoblast function, how they affect the pathogenesis of PE and evaluating the possibility of miRs in screening, diagnosis and treatment of PE.

Analysis of Circulating C19MC MicroRNA as an Early Marker of Hypertension and Preeclampsia in Pregnant Patients: A Systematic Review

Preeclampsia and hypertension complicate several pregnancies. Identifying women at risk of developing these conditions is essential to establish potential treatment modalities. Biomarkers such as C19MC microRNA in pregnant patients wopuld assist in defining pregnancy surveillance and implementing interventions. This study sought to analyze circulating C19MC microRNA as an early marker of hypertension and preeclampsia in pregnant patients. A systematic review was undertaken using the following registers: disease registries, pregnancy registries, and pregnancy exposure registries, and the following databases: PubMed, CINAHL, Web of Science, Scopus, and EMBASE. The risk of bias was assessed using the Cochrane technique. From the 45 publications retrieved from the registers and databases, only 21 were included in the review after the removal of duplicates, screening, and eligibility evaluation. All 210 publications had a low risk of bias and illuminated the potential use of circulating C19MC microRNA as an early marker of hypertension and preeclampsia in pregnant patients. Therefore, it was concluded that C19MC microRNA can be used as an early marker of gestational preeclampsia and hypertension.

The long noncoding RNA TARID regulates the CXCL3/ERK/MAPK pathway in trophoblasts and is associated with preeclampsia

BACKGROUND

The widely accepted explanation of preeclampsia (PE) pathogenesis is insufficient trophoblast invasion and impaired uterine spiral artery remodeling. However, the underlying molecular mechanism remains unclear.

METHODS

We performed transcriptome sequencing on placentas of normal and PE patients and identified 976 differentially expressed long noncoding RNAs (lncRNAs). TCF21 antisense RNA inducing demethylation (TARID) was one of the most significantly differentially expressed lncRNAs and was negatively correlated with the systolic and diastolic blood pressure in PE patients. Furthermore, we verified the effect of TARID on the biological behavior of trophoblasts and performed UID mRNA-seq to identify the effectors downstream of TARID. Then, co-transfection experiments were used to better illustrate the interaction between TARID and its downstream effector.

RESULTS

We concluded that the downregulation of TARID expression may inhibit trophoblast infiltration and spiral artery remodeling through inhibition of cell migration, invasion, and tube formation mediated through the CXCL3/ERK/MAPK pathway.

CONCLUSIONS

Overall, these findings suggested that TARID may be a therapeutic target for PE through the CXCL3/ERK/MAPK pathway.

The Role of Cluster C19MC in Pre-Eclampsia Development

Pre-eclampsia is a placenta-related complication occurring in 2-10% of all pregnancies. miRNAs are a group of non-coding RNAs regulating gene expression. There is evidence that C19MC miRNAs are involved in the development of the placenta. Deregulation of chromosome 19 microRNA cluster (C19MC) miRNAs expression leads to impaired cell differentiation, abnormal trophoblast invasion and pathological angiogenesis, which can lead to the development of pre-eclampsia. Information was obtained through a review of articles available in PubMed Medline. Articles on the role of the C19MC miRNA in the development of pre-eclampsia published in 2009-2022 were analyzed. This review article summarizes the current data on the role of the C19MC miRNA in the development of pre-eclampsia. They indicate a significant increase in the expression of most C19MC miRNAs in placental tissue and a high level of circulating fractions in serum and plasma, both in the first and/or third trimester in women with PE. Only for miR-525-5p, low levels of plasma expression were noted in the first trimester, and in the placenta in the third trimester. The search for molecular factors indicating the development of pre-eclampsia before the onset of clinical symptoms seems to be a promising diagnostic route. Identifying women at risk of developing pre-eclampsia at the pre-symptomatic stage would avoid serious complications in both mothers and fetuses. We believe that miRNAs belonging to cluster C19MC could be promising biomarkers of pre-eclampsia development.

Study the relationship between long non-coding RNA (CCAT1) expression and CDK4 expression levels in Egyptian patients with preeclampsia

Background

Maternal and perinatal mortality is caused by a variety of factors, including preeclampsia. PE's onset and progression may be influenced by lncRNAs. The effect of long non-coding RNA (lncRNA) Colon cancer-associated transcription factor 1 (CCAT1) expression in the placenta of preeclampsia patients on preeclampsia progression was the focus of this investigation.

Objectives

The aim of the current study is to check if the levels of expression of Colon cancer-associated transcription factor 1 (CCAT1) and Cyclin-dependent protein kinase 4 (CDK4) are associated with preeclampsia vulnerability and biogenesis.

Subjects

and methods: This work included the participation of 160 people. Eighty of the patients had preeclampsia. The control group included 80 normal pregnant women. The two groups were almost of the same age. A thorough clinical examination was performed in all groups (including taking a detailed history, concentrating on parity, age and previous background of diabetes or hypertension). The expression levels of CCAT1 and CDK4 in placental tissue were determined using a real-time q PCR technique.

Results

Expression levels of CCAT1 and CDK4 differed significantly between the study groups. preeclamptic patients having the highest level of CCAT1in comparison with control group, However, preeclamptic patients having lower level of CDK4 than controls. There was a strong negative association between CDK4 expression level and DBP, SBP, creatinine, urea and CCAT1 level of expression in the preeclamptic group, whereas there was a positive correlation between CCAT1 level of expression and DBP, SBP, urea and creatinine in patients group.

Conclusion

Based on the findings of this study, it is possible that CCAT1 and CDK4 expression levels could be used to aid in the diagnosis and biogenesis of preeclampsia.

Integrative analysis of circulating microRNAs and the placental transcriptome in recurrent pregnancy loss

Recurrent pregnancy loss (RPL) is a major type of pathological pregnancy that still lacks reliable early diagnosis and effective treatment. The placenta is critical to fetal development and pregnancy success because it participates in critical processes such as early embryo implantation, vascular remodeling, and immunological tolerance. RPL is associated with abnormalities in the biological behavior of placental villous trophoblasts, resulting in aberrant placental function. MicroRNAs (miRNAs) are increasingly being recognized as essential regulators of placental development, as well as potential biomarkers. In this study, plasma miRNAs and placental messenger RNAs (mRNAs) from RPL patients and normal pregnant (NP) controls were sequenced and analyzed. Compared to those in NP controls, 108 circulating miRNAs and 1199 placental mRNAs were differentially expressed in RPL samples. A total of 140 overlapping genes (overlapping between plasma miRNA target genes and actual placental disorder genes) were identified, and functional enrichment analysis showed that these genes were mainly related to cell proliferation, angiogenesis, and cell migration. The regulatory network among miRNAs, overlapping genes, and downstream biological processes was analyzed by protein–protein interactions and Cytoscape. Moreover, enriched mRNAs, which were predictive targets of the differentially expressed plasma miRNAs miR-766-5p, miR-1285-3p, and miR-520a-3p, were accordingly altered in the placenta. These results suggest that circulating miRNAs may be involved in the pathogenesis of RPL and are potential noninvasive biomarkers for RPL.

Non-Coding RNAs and Prediction of Preeclampsia in the First Trimester of Pregnancy

Preeclampsia (PE) is a major cause of maternal and perinatal morbidity and mortality. The only fundamental treatment for PE is the termination of pregnancy. Therefore, not only severe maternal complications but also perinatal complications due to immaturity of the infant associated with early delivery are serious issues. The treatment and prevention of preterm onset preeclampsia (POPE) are challenging. In 2017, the ASPRE trial showed that a low oral dose of aspirin administered to POPE high-risk women in early pregnancy reduced POPE by 62%. A prediction algorithm at 11–13 weeks of gestation identifies POPE with 75% sensitivity when the false positive rate is set at 10%. New biomarkers to increase the accuracy of the prediction model for POPE high-risk women in early pregnancy are needed. In this review, we focused on non-coding RNAs (ncRNAs) as potential biomarkers for the prediction of POPE. Highly expressed ncRNAs in the placenta in early pregnancy may play crucial roles in placentation. Furthermore, placenta-specific ncRNAs have been detected in maternal blood. In this review, we summarized ncRNAs that were highly expressed in the primary human placenta in early pregnancy. We also presented highly expressed ncRNAs in the placenta that were associated with or predictive of the development of PE in an expression analysis of maternal blood during the first trimester of pregnancy. These previous studies showed that the chromosome 19 microRNA (miRNA) -derived miRNAs (e.g., miR-517-5p, miR-518b, and miR-520h), the hypoxia-inducible miRNA (miR-210), and long non-coding RNA H19, were not only highly expressed in the early placenta but were also significantly up-regulated in the blood at early gestation in pregnant women who later developed PE. These maternal circulating ncRNAs in early pregnancy are expected to be possible biomarkers for POPE.

miRNA Regulatory Networks Associated with Peripheral Vascular Diseases

A growing body of evidence indicates a crucial role of miRNA regulatory function in a variety of mechanisms that contribute to the development of diseases. In our previous work, alterations in miRNA expression levels and targeted genes were shown in peripheral blood mononuclear cells (PBMCs) from patients with lower extremity artery disease (LEAD), abdominal aortic aneurysm (AAA), and chronic venous disease (CVD) in comparison with healthy controls. In this paper, previously obtained miRNA expression profiles were compared between the LEAD, AAA, and CVD groups to find either similarities or differences within the studied diseases. Differentially expressed miRNAs were identified using the DESeq2 method implemented in the R programming software. Pairwise comparisons (LEAD vs. AAA, LEAD vs. CVD, and AAA vs. CVD) were performed and revealed 10, 8, and 17 differentially expressed miRNA transcripts, respectively. The functional analysis of the obtained miRNAs was conducted using the miRNet 2.0 online tool and disclosed associations with inflammation and cellular differentiation, motility, and death. The miRNet 2.0 tool was also used to identify regulatory interactions between dysregulated miRNAs and target genes in patients with LEAD, AAA, and CVD. The presented research provides new information about similarities and differences in the miRNA-dependent regulatory mechanisms involved in the pathogenesis of LEAD, AAA, and CVD.

Potential biomarkers and molecular mechanisms in preeclampsia progression

This study aimed to explore potential biomarkers and molecular mechanisms in preeclampsia (PE) progression. Gene expression profiles of GSE147776 and GSE96984 were downloaded, followed by the identification of common differentially expressed genes (co-DEGs) and common differentially expressed lncRNAs (co-DElncRNAs) in PE patients between the two datasets. Key genes were identified using gene set enrichment analysis (GSEA), followed by functional enrichment analyses. Subsequently, the miRNAs of key genes and miRNA-related lncRNAs were predicted, followed by the construction of the lncRNA–miRNA–gene ceRNA network. Furthermore, the key genes associated with different gestational stages were identified. As a result, 192 co-DEGs and 16 co-DElncRNAs were revealed from the two datasets. Based on two outstanding PE-associated pathways, including glaucoma and PE, identified by GSEA, ten key genes, including IGFBP1, CORIN, and C3, were revealed. Key genes, including IL1A and IL1B, were enriched in the developmental process involved in reproduction. Furthermore, ceRNAs, such as LINC00473-miR-4476-IL1A, LINC00473-miR-1291-IL1B, and NAV2-AS4-miR-6131-REN, were identified. Moreover, REN expression was significantly upregulated in the first- and second-trimester placentae compared to C-section-term placentae. In conclusion, these key genes may serve as novel biomarkers for PE. The detection of REN expression may help in the early prediction of PE and the initiation of prophylactic medical treatment.

Circulating non-coding RNAs as biomarkers in coronary artery disease

Coronary artery disease (CAD) is a leading cause of mortality worldwide. Atherosclerosis involves an interplay of different pathological mechanisms, such as progressive inflammation, abnormal lipid metabolism, and oxidative stress, and as such represents the basic pathological phenomenon underlying CAD. Atherosclerotic plaque narrows the lumen of coronary arteries, creating an ischemic environment for the heart muscle, which finally leads to clinical complications, such as acute myocardial infarction. Currently, there are no biomarkers that could predict plaque stability or major adverse cardiovascular events (MACE). Numerous functional non-coding RNA (ncRNA) species influence basic cellular functions, and as such play a role in the development and progression of CAD. Of these ncRNAs, micro RNAs (miRNAs) and long non-coding RNAs (lncRNAs) are the most investigated. Considering that ncRNAs detected in extracellular fluids can originate from different cells, circulating ncRNAs are being intensively investigated as potential biomarkers in the diagnosis and prognosis of CAD. In the following paper, we provide current insights into potential molecular mechanisms by which miRNAs and lncRNAs contribute to the pathology of CAD and discuss their potential role as biomarkers in diagnosis and prognosis of disease.