microRNA-29b contributes to pre-eclampsia through its effects on apoptosis, invasion and angiogenesis of trophoblast cells

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.

Air Pollution-Linked Epigenetic Modifications in Placental DNA: Prognostic Potential for Identifying Future Foetal Anomalies

Prenatal exposure to air pollution is a significant risk factor for the mother and the developing foetus. The accumulation of pollutants in the placenta can cause a self-cascade loop of pro-inflammatory cytokine responses and DNA double-strand breaks. Previous research has shown that airborne particulate matter can damage the epigenome and disturb mitochondrial machinery, ultimately impairing placental function. Mitochondria are essential for preserving cellular homeostasis, energy metabolism, redox equilibrium, and epigenetic reprogramming. As these organelles are subtle targets of environmental exposures, any disruption in the signaling pathways can result in epigenomic instability, which can impact gene expression and mitochondrial function. This, in turn, can lead to changes in DNA methylation, post-translational histone modifications, and aberrant expression of microRNAs in proliferating trophoblast cells. The placenta has two distinct layers, cytotrophoblasts, and syncytiotrophoblasts, each with its mitochondria, which play important roles in preeclampsia, gestational diabetes, and overall health. Foetal nucleic acids enter maternal circulation during placental development because of necrotic, apoptotic, and inflammatory mechanisms. These nucleic acids reflect normal or abnormal ongoing cellular changes during prenatal foetal development. Detecting cell-free DNA in the bloodstream can be a biomarker for predicting negative pregnancy-related outcomes and recognizing abnormalities in foetal growth. Hence, a thorough understanding of how air pollution induces epigenetic variations within the placenta could offer crucial insights into underlying mechanisms and prolonged repercussions on foetal development and susceptibility in later stages of life.

Exploring the role of exosomal MicroRNAs as potential biomarkers in preeclampsia

The complex pathogenesis of preeclampsia (PE), a significant contributor to maternal and neonatal mortality globally, is poorly understood despite substantial research. This review explores the involvement of exosomal microRNAs (exomiRs) in PE, focusing on their impact on the protein kinase B (AKT)/hypoxia-inducible factor 1-α (HIF1α)/vascular endothelial growth factor (VEGF) signaling pathway as well as endothelial cell proliferation and migration. Specifically, this article amalgamates existing evidence to reveal the pivotal role of exomiRs in regulating mesenchymal stem cell and trophoblast function, placental angiogenesis, the renin-angiotensin system, and nitric oxide production, which may contribute to PE etiology. This review emphasizes the limited knowledge regarding the role of exomiRs in PE while underscoring the potential of exomiRs as non-invasive biomarkers for PE diagnosis, prediction, and treatment. Further, it provides valuable insights into the mechanisms of PE, highlighting exomiRs as key players with clinical implications, warranting further exploration to enhance the current understanding and the development of novel therapeutic interventions.

Combined impact of Hepatitis B virus and gestational diabetes mellitus on ultrasound-measured fetal growth and adverse perinatal outcomes: A seven-year retrospective study

AIMS

To investigate the impact of pregnancy with combined hepatitis B virus (HBV) infection and Gestational diabetes mellitus (GDM) on fetal growth and adverse perinatal outcomes.

METHODS

All the pregnant women with HBV infection and/or GDM who delivered at Women's Hospital, Zhejiang University between January 2015, and September 2022 were included. A total of 1633 pregnant women were recruited in the final analysis, including 409 women with HBV infection and GDM, 396 with HBV infection only, 430 with GDM only, and 398 without HBV infection and GDM. Linear and logistic regression models were used to study the impact of pregnancy with combined HBV infection and GDM on fetal growth and adverse perinatal outcomes.

RESULTS

Pregnancy with combined HBV infection and GDM was associated with increased Z-scores on primary fetal ultrasound parameters and significantly increased the risk of fetal femur length overgrowth (OR: 2.88, 95 % CI: 1.13 ∼ 7.35), placental abruption (OR: 3.64, 95 % CI: 1.18 ∼ 11.22), and macrosomia (OR: 4.19, 95 % CI: 1.66 ∼ 10.56) compared to pregnancy without HBV infection and GDM.

CONCLUSIONS

Both maternal HBV infection and GDM are independently associated with adverse perinatal outcomes. Their combination further increases the risk of adverse perinatal outcomes.

The role and expression of pro/antiangiogenic factors and microRNAs in gestational hypertension and pre-eclampsia

OBJECTIVE

Pre-eclampsia and gestational hypertension are two common hypertensive disorders of pregnancy with pre-eclampsia accounting for high foetal and maternal morbidity and mortality rate. These disorders have an unknown aetiology and their hypertensive and end-organ pathophysiology may present too late in pregnancy. This makes the identification of early detection and differentiation markers vital. MicroRNAs have strongly been associated with pregnancy and their imbalance has been associated with the angiogenic dysregulation seen in pre-eclampsia. This study assesses the expression of pro- and antiangiogenic factors and their corresponding microRNAs in the maternal circulation of patients with pre-eclampsia and gestational hypertension.

STUDY DESIGN

We analyzed angiogenic factors expression (sEng, TGF-β, VEGF) normalized against housekeeping gene β-actin and microRNAs (miRs: 210, 29B, 126) normalized against miR U6, potentially associated with pre-eclampsia and gestational hypertension using the targeted qPCR technique. These analytes were examined from early-onset (<34 weeks) (EOPE) (n = 12), late-onset (>34 weeks) (LOPE) (n = 12) pre-eclampsia, gestational hypertension (GH) (n = 12) and two gestationally matched normotensive groups (NG1 and 2) (n = 12) each in South African women of African ancestry. Group comparisons of experimental vs. control groups were assessed using t-test analysis for significance and represented as fold change expression.

RESULTS

The relative expression in group comparisons showed significant (p < 0.05) fold change of VEGF, TGF-β, sEng and miR126 in the EOPE vs. NG1. The GH vs. NG1 exhibited significant changes in VEGF, TGF-β, miR126, miR210 and miR29B. The LOPE vs. NG2 showed significant relative expression in all the angiogenic factors (VEGF, TGF-β and sEng). The GH vs. NG2 showed significant expression in VEGF and miR29B. The LOPE vs. EOPE showed significant fold changes in VEGF and miR210. Finally, only the GH vs. EOPE showed significant differences in miR210 and miR29B (p < 0.05).

CONCLUSION

This study provides better insights into angiogenic factors and microRNAs specificity to the subtypes of gestational hypertensive disorders in pregnancy. Relative expression analysis of angiogenic factors and microRNAs showed possible novel characteristics of gestational hypertension, and potential common molecular and pathological profiles with pre-eclampsia. Furthermore, we postulate that sEng and miR29B could be early detection markers for pre-eclampsia and gestational hypertension, respectively.

Immunomodulation of cytokine signalling at feto-maternal interface by microRNA-223 and -150-5p in infection-associated spontaneous preterm birth

Spontaneous preterm birth (sPTB) is a global health concern and it is the most prevalent cause of infant mortality and morbidity with occurrence rate of 5 - 18% worldwide. Studies suggest infection and infection-driven activation of inflammatory responses are the potential risk factors for sPTB. MicroRNAs (miRNAs) are thought to control the expression of several immune genes, making them crucial components of the intricate immune regulatory network and the dysregulation of miRNAs in placenta has been associated to several pregnancy-related complications. However, studies on possible role of miRNAs in immunomodulation of cytokine signalling in infection-associated sPTB are scarce. Present study aimed to investigate expression/ correlation of a few circulating miRNAs (miR-223, -150-5p, -185-5p, -191-5p), miRNA target genes and associated cytokines in sPTB women found infected with Chlamydia trachomatis/ Mycoplasma hominis/ Ureaplasma urealyticum. Non-heparinized blood and placental sample were collected from 140 sPTB and 140 term women visiting Safdarjung hospital, New Delhi (India) for conducting PCR and RT-PCR for pathogen detection and miRNA/ target gene/ cytokine expression, respectively. Common target genes of differentially expressed miRNAs were obtained from databases. The correlation between select target genes/ cytokines and serum miRNAs was determined by Spearman's rank correlation. 43 sPTB were infected with either pathogen and a significant upregulation of serum miRNAs was observed. However, miR-223 and 150-5p showed maximum fold-change (4.78 and 5.58, respectively) in PTB versus control group. IL-6ST, TGF-β R3 and MMP-14 were important target genes among 454 common targets, whereas, IL-6 and TGF-β were associated cytokines. miR-223 and 150-5p showed significant negative correlation with IL-6ST/ IL-6/ MMP-14 and positive correlation with TGF-β R3/ TGF-β. A significant positive correlation was found between IL-6ST and IL-6, TGF-β R3 and TGF-β. However, miR-185-5p and 191-5p were not significantly correlated. Although post-transcriptional validation is required, yet on the basis of mRNA findings, the study concludes that miR-223 and 150-5p are apparently of clinical importance in regulation of inflammatory processes during infection-associated sPTB.

Associations of maternal and placental extracellular vesicle miRNA with preeclampsia

Introduction: Gestational vascular complications (GVCs), including gestational hypertension and preeclampsia, are leading causes of maternal morbidity and mortality. Elevated levels of extracellular vesicles (EVs), in GVC have been linked to vascular injury. This study aims to characterize placental and circulating EV miRNA in GVCs, and explores the involvement of EV-miRNA in GVC, and whether they may be used to distinguish between placental and maternal pathologies. Methods: Blood samples were obtained from 15 non-pregnant (NP), 18 healthy-pregnant (HP), and 23 women with GVC during the third trimester. Placental sections were obtained after caesarian section. Platelet-poor-plasma (PPP) and EV pellets were characterized: EV size/concentration, protein content and miRNA expression were measured by nanoparticle tracking analysis, western blot, nano-string technology and RT-PCR. The effects of EVs on trophoblasts and EC miRNA expression were evaluated. Results: Higher EVs concentrations were observed in HP-PPP and GVC-PPP (p < 0.0001) compared to the NP-PPP. The concentration of large EVs (>100 nm) was higher in PPP and EV pellets of HP and GVC compared to the NP group. EV pellets of pregnant women demonstrated lower expression of exosomal markers CD63/CD81 compared to NP-EVs. GVC-EVs expressed more human placental lactogen (hPL) hormone than HP-EVs, reflecting their placental origin. Screening of miRNAs in EV pellets and in PPP identified certain miRNAs that were highly expressed only in EVs pellets of the HP (13%) and GVC groups (15%), but not in the NP group. Differences were detected in the expression of hsa-miR-16-5p, hsa-miR-210, and hsa-miR-29b-3p. The expression of hsa-miR-16-5p and hsa-miR-210 was low in EV pellets obtained from NP, higher in HP-EVs, and significantly lower in GVC-EVs. Except for hsa-miR-29b-3p, which was upregulated in GVC, no significant differences were found in the levels of other miRNAs in placental sections. Exposure to GVC-EVs resulted in higher expression of hsa-miR-29b-3p compared to cells exposed to HP-EVs in villous trophoblasts, but not in EC. Conclusion: Expression of hsa-miR-16-5p and hsa-miR-210 reflects maternal pathophysiological status, while hsa-miR-29b-3p reflects placental status. These findings suggest that EV-miRNA are involved in GVC, and that they may be used to distinguish between pathologies of placental and maternal origins in preeclampsia.

Placental Therapeutic Targets and Nanodelivery Systems

Pregnancy complications affect millions of women each year. Some of these diseases have high morbidity and mortality such as preeclampsia. At present, there is no safe and effective treatment for pregnancy complications, so it is still a difficult clinical problem. As many pregnancy complications are closely related to placental dysplasia, placenta-specific therapy, as an important method, is expected to be a safe, effective, and specific therapeutic strategy. This review explains in detail the placenta physiological structure, characteristics, and action mechanism of some biomolecules and signaling pathways that play roles in normal development and disorders of the development of the placenta, and how to use these biomolecules as therapeutic targets when the placenta disorder causes disease, combining the latest progress in the field of nanodelivery systems, so as to lay a foundation for the development of placenta-specific therapy of pregnancy complications.

Preeclamptic Women Have Disrupted Placental microRNA Expression at the Time of Preeclampsia Diagnosis: Meta-Analysis

Introduction: Preeclampsia (PE) is a pregnancy-associated, multi-organ, life-threatening disease that appears after the 20th week of gestation. The aim of this study was to perform a systematic review and meta-analysis to determine whether women with PE have disrupted miRNA expression compared to women who do not have PE. Methods: We conducted a systematic review and meta-analysis of studies that reported miRNAs expression levels in placenta or peripheral blood of pregnant women with vs. without PE. Studies published before October 29, 2021 were identified through PubMed, EMBASE and Web of Science. Two reviewers used predefined forms and protocols to evaluate independently the eligibility of studies based on titles and abstracts and to perform full-text screening, data abstraction and quality assessment. Standardized mean difference (SMD) was used as a measure of effect size. Results: 229 publications were included in the systematic review and 53 in the meta-analysis. The expression levels in placenta were significantly higher in women with PE compared to women without PE for miRNA-16 (SMD = 1.51,95%CI = 0.55-2.46), miRNA-20b (SMD = 0.89, 95%CI = 0.33-1.45), miRNA-23a (SMD = 2.02, 95%CI = 1.25-2.78), miRNA-29b (SMD = 1.37, 95%CI = 0.36-2.37), miRNA-155 (SMD = 2.99, 95%CI = 0.83-5.14) and miRNA-210 (SMD = 1.63, 95%CI = 0.69-2.58), and significantly lower for miRNA-376c (SMD = -4.86, 95%CI = -9.51 to -0.20). An increased level of miRNK-155 expression was found in peripheral blood of women with PE (SMD = 2.06, 95%CI = 0.35-3.76), while the expression level of miRNA-16 was significantly lower in peripheral blood of PE women (SMD = -0.47, 95%CI = -0.91 to -0.03). The functional roles of the presented miRNAs include control of trophoblast proliferation, migration, invasion, apoptosis, differentiation, cellular metabolism and angiogenesis. Conclusion: miRNAs play an important role in the pathophysiology of PE. The identification of differentially expressed miRNAs in maternal blood creates an opportunity to define an easily accessible biomarker of PE.

MiR-29b-3p affects growth and biological functions of human extravillous trophoblast cells by regulating bradykinin B2 receptor

INTRODUCTION

This study investigated miR-29b-3p's effects and mechanisms in preeclampsia development.

MATERIAL AND METHODS

In this study, we analysed the pathology and expression of miR-29b-3p and B2R mRNA from normal and preeclampsia placenta tissues using hematoxylin and eosin staining and RT-qPCR assay. For cell experiments, we used transwell assay CCK-8, flow cytometry and wound healing assay to determine the effects and correlation of miR-29b-3p and B2R in HTR-8/SVneo cell proliferation, apoptosis, cell cycle, cell invasion and migration in a preeclampsia cell model. Moreover, the mechanisms were determined using Western blot or immunofluorescence in different groups.

RESULTS

Clinical analysis revealed that miR-29b-3p gene expression dramatically increased with increasing degree of preeclampsia (p < 0.001 or p < 0.05, respectively). The HTR-8/SVneo cell biological activities of the model group were significantly depressed (p < 0.001). However, with miR-29b-3p inhibitor or B2R transfection, the HTR-8/SVneo cell biological activities significantly recovered (p < 0.001). Western blot assay showed that B2R, VEGF-A, CCND-1, MMP-2 and MMP-9 levels were suppressed in the model group, compared with those in the NC groups (p < 0.001, respectively). With miR-29b-3p inhibitor or B2R transfection, the protein expression levels of B2R, VEGF-A, CCND-1, MMP-2 and MMP-9 dramatically increased (p < 0.001, respectively).

CONCLUSIONS

The down-regulation of miR-29b-3p could improve HTR-8/SVneo cell biological activities in a preeclampsia cell model by targeting B2R.

Epigenetic processes during preeclampsia and effects on fetal development and chronic health

Preeclampsia (PE), the leading cause of maternal and fetal morbidity and mortality, is associated with poor fetal growth, intrauterine growth restriction (IUGR) and low birth weight (LBW). Offspring of women who had PE are at increased risk for cardiovascular (CV) disease later in life. However, the exact etiology of PE is unknown. Moreover, there are no effective interventions to treat PE or alleviate IUGR and the developmental origins of chronic disease in the offspring. The placenta is critical to fetal growth and development. Epigenetic regulatory processes such as histone modifications, microRNAs and DNA methylation play an important role in placental development including contributions to the regulation of trophoblast invasion and remodeling of the spiral arteries. Epigenetic processes that lead to changes in placental gene expression in PE mediate downstream effects that contribute to the development of placenta dysfunction, a critical mediator in the onset of PE, impaired fetal growth and IUGR. Therefore, this review will focus on epigenetic processes that contribute to the pathogenesis of PE and IUGR. Understanding the epigenetic mechanisms that contribute to normal placental development and the initiating events in PE may lead to novel therapeutic targets in PE that improve fetal growth and mitigate increased CV risk in the offspring.

Increased expression of lncRNA SNHG7 promotes the cell viability, migration, and invasion in pre-eclampsia via modulating the miR-214-5p/TWIST1 axis

PURPOSE

This study is aimed to elucidate the molecular mechanism of lncRNA SNHG7 on pre-eclampsia (PE).

METHODS

The expression of SNHG7, miR-214-5p and TWIST1 in PE placental tissues was detected by qRT-PCR. The regulatory mechanism of SNHG7/miR-214-5p/TWIST1 axis on PE was determined using MTT, wound healing, transwell invasion, and western blot assays.

RESULTS

In PE pregnancies, SNHG7 and TWIST1 were decreased, while miR-214-5p was increased.The elevated miR-214-5p and decreased TWIST1 partly eliminated the promoting effects of SNHG7 up-regulation on the viability and metastasis of JEG-3 cells.

CONCLUSIONS

Up-regulated SNHG7 protects against PE through modulating the miR-214-5p/TWIST1 axi.

MicroRNAs targeting VEGF are related to vascular dysfunction in preeclampsia

In preeclampsia (PE), pre-existent maternal endothelial dysfunction leads to impaired placentation and vascular maladaptation. The vascular endothelial growth factor (VEGF) pathway is essential in the placentation process and VEGF expression is regulated through post-transcriptional modification by microRNAs (miRNAs). We investigated the expression of VEGF-related circulating miR-16, miR-29b, miR-126, miR-155 and miR-200c in PE vs healthy pregnancies (HPs), and their relation with vascular function, oxidative stress (OS) and systemic inflammation. In this case-control study, 24 women with early PE (<34 weeks) were compared with 30 women with HP. Circulating microRNA levels (RT-qPCR), OS and systemic inflammation were assessed in plasma samples (PE 29.5 vs HP 25.8 weeks) and related to extensive in vivo vascular function (flow-mediated dilatation (FMD), modified FMD (mFMD), carotid-femoral pulse wave velocity (CF-PWV), heart rate corrected augmentation index (AIx75) and reactive hyperemia index (RHI)). FMD, CF-PWV, AIx75 and RHI were all significantly impaired in PE (P<0.05). PE patients had reduced levels of miR-16 (5.53 ± 0.36 vs 5.84 ± 0.61) and increased levels of miR-200c (1.34 ± 0.57 vs 0.97 ± 0.68) (P<0.05). Independent of age and parity, miR-16 was related to impaired FMD (β 2.771, 95% C.I.: 0.023-5.519, P=0.048) and mFMD (β 3.401, 95% C.I.: 0.201-6.602, P=0.038). Likewise, miR-200c was independently associated with CF-PWV (β 0.513, 95% C.I.: 0.034-0.992, P=0.036). In conclusion, circulating levels of miR-16 were lower in PE, which correlated with impaired endothelial function. Circulating miR-200c was increased in PE and correlated with higher arterial stiffness. These findings suggest a post-transcriptional dysregulation of the VEGF pathway in PE and identify miR-16 and miR-200c as possible diagnostic biomarkers for PE.

Roles of noncoding RNAs in preeclampsia

Preeclampsia (PE) is an idiopathic disease that occurs during pregnancy. It comprises multiple organ and system damage, and can seriously threaten the safety of the mother and infant throughout the perinatal period. As the pathogenesis of PE is unclear, there are few specific remedies. Currently, the only way to eliminate the clinical symptoms is to terminate the pregnancy. Although noncoding RNA (ncRNA) was once thought to be the "junk" of gene transcription, it is now known to be widely involved in pathological and physiological processes, including pregnancy-related disorders. Moreover, there is growing evidence that the unbalanced expression of specific ncRNA is involved in the pathogenesis of PE. In the present review, we summarize the expression patterns of ncRNAs, i.e., microRNAs (miRNAs), long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs), and the functional mechanisms by which they affect the development of PE, and examine the clinical significance of ncRNAs as biomarkers for the diagnosis of PE. We also discuss the contributions made by genetic polymorphisms and epigenetic ncRNA regulation to PE. In the present review, we wish to explore and reinforce the clinical value of ncRNAs as noninvasive biomarkers of PE.

Recent Advances of MicroRNAs, Long Non-coding RNAs, and Circular RNAs in Preeclampsia

Preeclampsia is a clinical syndrome characterized by multiple-organ dysfunction, such as maternal hypertension and proteinuria, after 20 weeks of gestation. It is a common cause of fetal growth restriction, fetal malformation, and maternal death. At present, termination of pregnancy is the only way to prevent the development of the disease. Non-coding RNAs, including microRNAs, long non-coding RNAs, and circular RNAs, are involved in important pathological and physiological functions in life cycle activities including ontogeny, reproduction, apoptosis, and cell reprogramming, and are closely associated with human diseases. Accumulating evidence suggests that non-coding RNAs are involved in the pathogenesis of preeclampsia through regulation of various physiological functions. In this review, we discuss the current evidence of the pathogenesis of preeclampsia, introduce the types and biological functions of non-coding RNA, and summarize the roles of non-coding RNA in the pathophysiological development of preeclampsia from the perspectives of oxidative stress, hypoxia, angiogenesis, decidualization, trophoblast invasion and proliferation, immune regulation, and inflammation. Finally, we briefly discuss the potential clinical application and future prospects of non-coding RNA as a biomarker for the diagnosis of preeclampsia.

The Involvement of MicroRNAs in SARS-CoV-2 Infection Comorbid with HIV-Associated Preeclampsia

Purpose of Review

This review investigated the potential role of microRNAs (miRNAs) in the synergy of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, preeclampsia (PE), and human immunodeficiency virus (HIV) infection. Maternal health is a great concern when treating pregnant women fighting this triad of diseases, which is highly prevalent in South Africa. MicroRNAs are involved in fine-tuning of physiological processes. Disruptions to the balance of this minute protein can lead to various physiological changes that are sometimes pathological.

Recent Findings

MicroRNAs have recently been implicated in PE and have been linked to the anti-angiogenic imbalance evident in PE. Recent in silico studies have identified potential host miRNAs with anti-viral properties against SARS-CoV-2 infection. Studies have demonstrated dysregulated expression of several miRNAs in HIV-1 infection along with the ability of HIV-1 to downregulate anti-viral host microRNAs.

Summary

This review has highlighted the significant gap in literature on the potential of miRNAs in women with HIV-associated PE in synergy with the novel SARS-CoV-2 infection. In addition, this review has provided evidence of the critical role that the epigenetic regulatory mechanism of miRNA plays in viral infections and PE, thereby providing a foundation for further research investigating the potential of therapeutic miRNA development with fewer side-effects for pregnant women.

Integrin β1 regulates proliferation, apoptosis, and migration of trophoblasts through activation of phosphoinositide 3 kinase/protein kinase B signaling

AIMS

Abnormal trophoblast invasion is one of the onsets of preeclampsia (PE). Studies found that integrin β1 (ITGB1) is closely related to PE, but the role of ITGB1 in the progression of trophoblast remained unclear. Therefore, we studied the functional role of ITGB1 in PE and its effects on trophoblast.

METHODS

ITGB1 expression in placenta tissues was determined by quantitative real-time polymerase chain reaction (qRT-PCR). The effects of transfection on HTR-8/SVneo cells were analyzed by qRT-PCR and western blotting. After cell transfection, colony formation assay, flow cytometry, wound healing assay, and transwell assay were performed to detect cell proliferation, apoptosis, migration, and invasion. Western blotting assay was used for determining phosphoinositide 3 kinase (PI3K) and protein kinase B (Akt) signaling pathway. After inhibiting PI3K/Akt pathway, apoptosis-regulated proteins were detected by western blotting, and the effects of inhibitor on the migration and invasion changes were examined.

RESULTS

ITGB1 was downregulated in placenta tissues from PE patients, as compared with normal. ITGB1 overexpression in HTR-8/SVneo cells enhanced cell proliferation, migration, and invasion, reduced cell apoptosis, and improved phosphorylation of PI3K and Akt. However, ITGB1 depletion resulted in an opposite effect to its overexpression. Inhibition of PI3K/Akt pathway completely blocked the effect of ITGB1 overexpression on cells, because we observed that apoptosis-regulated proteins were highly upregulated, and that cell migration and invasion were reduced.

CONCLUSION

ITGB1 regulated HTR-8/SVneo cell progression by activation of the PI3K/Akt pathway.

Analysis of differential expression of hypoxia-inducible microRNA-210 gene targets in mild and severe preeclamptic patients

Preeclampsia (PE) is a multi-system disorder that is specific to human pregnancy. Inadequate oxygenation of uterus and placenta is considered as one of the leading causes for the disease. MicroRNA-210(miR-210) is one of the prime molecules that has emerged in response to hypoxia. The objective of this study was to determine miR-210 expression patterns in plasma from severe PE and mild PE patients, and how that affects the expression of miR-210 target genes. The expression levels of miR-210 were validated using reverse transcription-quantitative PCR in plasma of severe PE (15) and mild PE (15) patients in comparison to controls subjects (15) with normal pregnancy. Then, the association between miR-210 and its downstream genes was validated by using human miR-210 targets RT2 profiler PCR Array. Both the categories (mild and severe) showed significantly high miR-210 expression levels. Also out of the 84 hypoxia miR-210 associated genes screened using mRNA, 18 genes were found to be differentially expressed in severe PE whereas 16 genes in mild PE cases with varying magnitude. All the genes in both the PE groups were found downregulated in comparison to controls. These downregulated genes expressed in both the cases were shown to be participating in immunosuppression, apoptosis, cell growth, signaling, angiogenesis, DNA repair. This study provides novel data on the genes that work downstream of miR-210 and how dysregulated expression of miR-210 can affect their expression and in turn functioning which can be associated with PE risk and severity. This study is the very first to determine the effect of miR-210 expression levels on associated genes in plasma samples.

Extracellular vesicle microRNA in early versus late pregnancy with birth outcomes in the MADRES study

Circulating miRNA may contribute to the development of adverse birth outcomes. However, few studies have investigated extracellular vesicle (EV) miRNA, which play important roles in intercellular communication, or compared miRNA at multiple time points in pregnancy. In the current study, 800 miRNA were profiled for EVs from maternal plasma collected in early (median: 12.5 weeks) and late (median: 31.8 weeks) pregnancy from 156 participants in the MADRES Study, a health disparity pregnancy cohort. Associations between miRNA and birth weight, birth weight for gestational age (GA), and GA at birth were examined using covariate-adjusted robust linear regression. Differences by infant sex and maternal BMI were also investigated. Late pregnancy measures of 13 miRNA were associated with GA at birth (P_FDR<0.050). Negative associations were observed for eight miRNA (miR-4454+ miR-7975, miR-4516, let-7b-5p, miR-126-3p, miR-29b-3p, miR-15a-5p, miR-15b-5p, miR-19b-3p) and positive associations for five miRNA (miR-212-3p, miR-584-5p, miR-608, miR-210-3p, miR-188-5p). Predicted target genes were enriched (P_FDR<0.050) in pathways involved in organogenesis and placental development. An additional miRNA (miR-107), measured in late pregnancy, was positively associated with GA at birth in infants born to obese women (P_FDR for BMI interaction = 0.011). In primary analyses, the associations between early pregnancy miRNA and birth outcomes were not statistically significant (P_FDR≥0.05). However, sex-specific associations were observed for early pregnancy measures of 37 miRNA and GA at birth (P_FDR for interactions<0.050). None of the miRNA were associated with fetal growth measures (P_FDR≥0.050). Our findings suggest that EV miRNA in both early and late pregnancy may influence gestational duration.

Placenta-Derived MicroRNAs in the Pathophysiology of Human Pregnancy

In placental mammals, reproductive success, and maternal-fetal health substantially depend on a well-being placenta, the interface between the fetus and the mother. Disorders in placental cells are tightly associated with adverse pregnancy outcomes including preeclampsia (PE), fetal growth restriction, etc. MicroRNAs (miRNAs) represent small non-coding RNAs that regulate post-transcriptional gene expression and are integral to a wide range of healthy or diseased cellular proceedings. Numerous miRNAs have been detected in human placenta and increasing evidence is revealing their important roles in regulating placental cell behaviors. Recent studies indicate that placenta-derived miRNAs can be released to the maternal circulation via encapsulating into the exosomes, and they potentially target various maternal cells to provide a hormone-like means of intercellular communication between the mother and the fetus. These placental exosome miRNAs are attracting more and more attention due to their differential expression in pregnant complications, which may provide novel biomarkers for prediction of the diseases. In this review, we briefly summarize the current knowledge and the perspectives of the placenta-derived miRNAs, especially the exosomal transfer of placental miRNAs and their pathophysiological relevance to PE. The possible exosomal-miRNA-targeted strategies for diagnosis, prognosis or therapy of PE are highlighted.

Depletion of CTCF disrupts PSG gene expression in the human trophoblast cell line Swan 71

Pregnancy‐specific glycoproteins (PSGs) are fetal proteins secreted by the placenta during pregnancy. The PSG level in maternal serum is an indicator of risk for pregnancy complications. However, little is known about the molecular mechanisms underlying PSG gene expression. Recently, the importance of epigenetic regulation of placental genes has been emphasized in the study of developmental defects and placental disease. In this study, the role of the CCCTC‐binding factor (CTCF) in regulation of PSG expression was investigated to better understand the epigenetic regulatory mechanisms of the PSG genes. Inhibition of CTCF expression disturbed transcription of several PSG genes: PSG1, PSG2, PSG4, PSG5, PSG8, and PSG9 were upregulated and PSG6 and PSG11 were downregulated. These transcriptional changes were correlated with decreased CTCF binding and changes in histone modification at the PSG promoters. Our data demonstrate that CTCF is a potential mediator in the regulation of PSG gene expression.

The Potent Antioxidant MitoQ Protects Against Preeclampsia During Late Gestation but Increases the Risk of Preeclampsia When Administered in Early Pregnancy

Aims: Although preeclampsia (PE) has been attributed to excessive oxidative stress (OS) in the placenta, mild antioxidants failed to prevent PE in clinical trials. As mitochondria are a major source of OS, this study assessed the potential of a potent mitochondria-targeting antioxidant MitoQ in the prevention of PE. Results: Placentas from women with PE and from reduced uterine perfusion pressure (RUPP) mice demonstrated significantly higher OS, along with increased mitochondrial damage and compromised glutathione peroxidase (GPx) activities. MitoQ administration during late gestation alleviated RUPP-induced PE; whereas early-pregnancy MitoQ treatment not only exacerbated blood pressure, fetal growth restriction, and proteinuria but also reduced the labyrinth/spongiotrophoblast ratio and blood sinuses in the labyrinth. Invasion (Matrigel transwell) and migration (wound healing assay) of trophoblasts were greatly improved by 1 μM hydrogen peroxide (H₂O₂), but this improvement was abolished by MitoQ or MitoTempo. Mild OS enhanced the expression of miR-29b-3p, which regulates five genes involved in viability and mobility, in HTR8-S/Vneo cells. Innovation and Conclusions: Although the potent mitochondrial-targeting antioxidant MitoQ protects against hypertension and kidney damage induced by RUPP in mice when administered in late gestation, it exacerbates the PE-like phenotype when given in early gestation by interfering with placenta formation because mild OS is required to stimulate trophoblast proliferation, invasion, and migration. Eliminating trophoblastic OS during early pregnancy may lead to compromised placentation and a risk of diseases of placental origin. Therefore, antioxidant therapy for pregnant women should be carefully considered.

Overexpression of microRNA-29b inhibits epithelial-mesenchymal transition and angiogenesis of colorectal cancer through the ETV4/ERK/EGFR axis

BACKGROUND

Recent studies have reported the involvement of microRNA-29 (miR-29) family members in human cancers through their ability to regulate cellular functions. The present study investigated biological function of miR-29b in colorectal cancer (CRC).

METHODS

CRC tissues and adjacent normal tissues were collected and the expression of ETV4 and miR-29b in the tissues were identified. The relationship between ETV4 and miR-29b or ETV4 expression and the EGFR promoter was identified using dual-luciferase reporter gene and CHIP assays. The proliferation, invasion, migration, and apoptosis of CRC HCT116 cells were assayed using MTT assay, Scratch test, Transwell assay, and flow cytometry, respectively. Also, expression of epithelial-mesenchymal transition (EMT) markers, angiogenic factors, and vasculogenic mimicry formation were evaluated using RT-qPCR and Western blot.

RESULTS

ETV4 was upregulated, while miR-29b expression was decreased in CRC tissues. ETV4 was identified as a target gene of miR-29b, which in turn inactivated the ERK signaling pathway by targeting ETV4 and inhibiting EGFR transcription. Transfection with miR-29b mimic, siRNA-ETV4, or ERK signaling pathway inhibitor U0126 increased expression of E-cadherin and TSP-1, and CRC cell apoptosis, yet reduced expression of ERK1/2, MMP-2, MMP-9, Vimentin, and VEGF, as well as inhibiting EMT, angiogenesis, and CRC cell migration and invasion. The EMT, angiogenesis and cancer progression induced by miR-29b inhibitor were reversed by siRNA-mediated ETV4 silencing.

CONCLUSIONS

miR-29b suppresses angiogenesis and EMT in CRC via the ETV4/ERK/EGFR axis.

Integrated Analysis of Hub Genes and MicroRNAs in Human Placental Tissues from In Vitro Fertilization-Embryo Transfer

OBJECTIVE

Supraphysiological hormone exposure, in vitro culture and embryo transfer throughout the in vitro fertilization-embryo transfer (IVF-ET) procedures may affect placental development. The present study aimed to identify differences in genomic expression profiles between IVF-ET and naturally conceived placentals and to use this as a basis for understanding the underlying effects of IVF-ET on placental function.

METHODS

Full-term human placental tissues were subjected to next-generation sequencing to determine differentially expressed miRNAs (DEmiRs) and genes (DEGs) between uncomplicated IVF-ET assisted and naturally conceived pregnancies. Gene ontology (GO) enrichment analysis and transcription factor enrichment analysis were used for DEmiRs. MiRNA-mRNA interaction and protein-protein interaction (PPI) networks were constructed. In addition, hub genes were obtained by using the STRING database and Cytoscape. DEGs were analyzed using GO and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Differentially expressed miRNAs were validated through qRT-PCR.

RESULTS

Compared against natural pregnancies, 12 DEmiRs and 258 DEGs were identified in IVF-ET placental tissues. In a validation cohort, it was confirmed that hsa-miR-204-5p, hsa-miR-1269a, and hsa-miR-941 were downregulation, while hsa-miR-4286, hsa-miR-31-5p and hsa-miR-125b-5p were upregulation in IVF-ET placentas. Functional analysis suggested that these differentially expressed genes were significantly enriched in angiogenesis, pregnancy, PI3K-Akt and Ras signaling pathways. The miRNA-mRNA regulatory network revealed the contribution of 10 miRNAs and 109 mRNAs while EGFR was the most highly connected gene among ten hub genes in the PPI network.

CONCLUSION

Even in uncomplicated IVF-ET pregnancies, differences exist in the placental transcriptome relative to natural pregnancies. Many of the differentially expressed genes in IVF-ET are involved in essential placental functions, and moreover, they provide a ready resource of molecular markers to assess the association between placental function and safety in IVF-ET offspring.

Maternal HBsAg carriers and pregnancy outcomes: a retrospective cohort analysis of 85,190 pregnancies

Background

Nowadays, a positive HBV carrier status is common among pregnant women, especially in endemic areas (such as China), little is known about the impact of maternal HBV infection on the risk of adverse pregnancy outcomes. Pregnant women with HBV infection often develop obstetric complications, such as pregnancy-induced hypertension (PIH) syndrome, postpartum hemorrhage, and gestational diabetes mellitus (GDM), and their infants often exhibit neonatal complications.

Methods

This study undertook a retrospective cohort analysis to explore the association of HBV carrier status with adverse pregnancy outcomes. A cohort of 85,190 women including 9699 HBsAg-positive and 73,076 HBsAg-negative pregnancies was retrospectively analyzed.

Results

It’s found that HBsAg-positive pregnancies may result in higher risk of various maternal outcomes such as ICP (OR 3.4,95%CI 2.80 to 4.13), postpartum hemorrhage (OR 1.16,95%CI 1.00 to 1.34). Interestingly, there was a decreased risk of Preeclampsia (OR 0.91,95%CI 0.87 to 0.96), premature rupture of membrane (OR 0.91,95%CI 0.87 to 0.96) and gestational hypertension (OR 0.828,95%CI 0.701 to 0.978). And in vaginal delivery subgroup analysis, It’s found that the HBsAg-positive group had a higher risk of placental abruption (OR, 1.44; 95% CI, 1.16–1.79).

Conclusions

The present results suggest that compared with HBV positive pregnancies were more likely to be ICP and postpartum hemorrhage. HBV-positive pregnant women underwent vaginal delivery were more likely to have placental abruption and premature birth compared with HBV-negative women. Obstetricians should be aware of ICP, postpartum hemorrhage, placental abruption and premature birth in HBV-positive pregnant women.

Laminins Regulate Placentation and Pre-eclampsia: Focus on Trophoblasts and Endothelial Cells

Pre-eclampsia is a systemic vascular disease characterized by new-onset hypertension and/or proteinuria at ≥20 weeks of gestation and leads to high rates of maternal and perinatal morbidity and mortality. Despite the incomplete understanding of pre-eclampsia pathophysiology, it is accepted that insufficient spiral artery remodeling and endothelial dysfunction are major contributors. Laminins (LNs) are a vital family of extracellular matrix (ECM) molecules present in basement membranes that provide unique spatial and molecular information to regulate implantation and placentation. LNs interact with cell surface receptors to trigger intracellular signals that affect cellular behavior. This mini-review summarizes the role of LNs in placental development during normal pregnancy. Moreover, it describes how LN deficiency can lead to the pre-eclampsia, which is associated with trophoblast and vascular endothelial dysfunction. New research directions and the prospect of clinical diagnosis of LN deficiency are discussed, and the gaps in basic and clinical research in this field are highlighted.

MicroRNA-27a inhibits trophoblast cell migration and invasion by targeting SMAD2: Potential role in preeclampsia

Preeclampsia (PE) is a severe idiopathic obstetric complication that occurs worldwide. Insufficient trophoblast invasion is a characteristic of the pathogenesis of PE. MicroRNA-27a (miR-27a) has been reported to be highly expressed in PE placentas. The aim of the present study was to investigate the role and underlying mechanisms of miR-27a in the pathogenesis of PE. The expression level of miR-27a was evaluated in the placenta and serum from patients with PE and healthy pregnant women. Cell Counting Kit-8 and flow cytometry assays were performed to detect human HTR-8/SVneo trophoblast proliferation and apoptosis after miR-27a overexpression or inhibition. In addition, Transwell assays were used to measure cell migration and invasion. A luciferase reporter assay was performed to determine the interaction between miR-27a and SMAD2. The present results suggested that miR-27a expression level was significantly increased in PE placentas and serum. In addition, miR-27a overexpression suppressed cell migratory and invasive abilities, impaired proliferation and promoted apoptosis in human trophoblasts. It was demonstrated that miR-27a may target SMAD and contribute to trophoblast invasion. Collectively, the results of the present study suggested that miR-27a inhibited trophoblast cell migration and invasion by targeting SMAD2, thus presenting a promising therapeutic target for PE.

Emerging Therapeutic Potential of Mesenchymal Stem/Stromal Cells in Preeclampsia

PURPOSE OF REVIEW

Preeclampsia is a dangerous pregnancy condition affecting both the mother and offspring. It is a multifactorial disease with poorly understood pathogenesis, lacking effective treatments. Maternal immune response, inflammation and oxidative stress leading to endothelial dysfunction are the most prominent pathogenic processes implicated in preeclampsia development. Here, we give a detailed overview of the therapeutic applications and mechanisms of mesenchymal stem/stromal cells (MSCs) as a potential new treatment for preeclampsia.

RECENT FINDINGS

MSCs have gained growing attention due to low immunogenicity, easy cultivation and expansion in vitro. Accumulating evidence now suggests that MSCs act primarily through their secretomes facilitating paracrine signalling that leads to potent immunomodulatory, pro-angiogenic and regenerative therapeutic effects. MSCs have been studied in different animal models of preeclampsia demonstrating promising result, which support further investigations into the therapeutic effects and mechanisms of MSC-based therapies in preeclampsia, steering these therapies into clinical trials.

LRP6 is involved in the proliferation, migration and invasion of trophoblast cells via miR‑346

Low‑density lipoprotein receptor‑related protein 6 (LRP6) promotes metastasis in numerous types of cancer; however, its role in trophoblast cells has been less frequently reported. In the present study, the effects of up‑ and downregulation of LRP6 on trophoblast cells were investigated accordingly. The study aimed to develop a therapeutic target for gestational choriocarcinoma. The expression levels of LRP6 in pre‑eclampsia (PE) tissues, trophoblast cell lines and gestational choriocarcinoma cells were determined using reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) assay. Double‑luciferase reporter analysis was conducted to detect the regulatory gene of LRP6. Furthermore, the proliferative, migratory and invasive abilities of trophoblasts and gestational choriocarcinoma cells were determined by CCK‑8, wound healing, and Transwell assays, respectively. The expression levels of the genes and proteins of interest [matrix metalloproteinase (MMP)‑2, MMP‑9, tissue inhibitor of metalloproteinase‑1 (TIMP‑1), and TIMP‑2] associated with tumor cell invasion were measured by performing RT‑qPCR and western blotting, respectively. The National Center for Biotechnology Information database revealed that LRP6 was relatively highly expressed in placental tissues, but was poorly expressed in PE tissues and trophoblast cell lines. The upregulation of LRP6 not only increased the activity, migration and invasion of trophoblast cells, but it also promoted the expression of MMP‑2 and MMP‑9, whereas it inhibited the expression levels of TIMP‑1 and TIMP‑2. Such results followed the opposite trend to those of downregulation of LRP6 in gestational choriocarcinoma cells. Moreover, LRP6 was predicted to be the target gene for microRNA (miR)‑346, which was highly expressed in PE tissues and trophoblast cell lines. The present study also revealed that LRP6 could reverse the effects of miR‑346 on the proliferation, migration and invasion of trophoblast cells. Therefore, considered collectively, the results of the present study have demonstrated that LRP6 is involved in the proliferation, migration and invasion of trophoblast cells via miR‑346, and that LRP6 may serve as a potential target in cancer treatment.

Exosomal encapsulation of miR-125a-5p inhibited trophoblast cell migration and proliferation by regulating the expression of VEGFA in preeclampsia

This study is aimed to examine the association between umbilical cord blood (UCB) derived exosomal microRNA (miRNA) with preeclampsia (PE) and to further explore the mechanism of a key differential gene (hsa-miR-125a-5p) in preeclampsia. Umbilical cord blood exosomal miRNA(exo-miRNA) from normal pregnant women and pregnant women with preeclampsia was processed via miRNA sequencing. Quantitative real-time polymerase chain reaction (QRT-PCR) was performed to assess the expression of miR-125a-5p in normal and PE placental tissues and peripheral blood derived exosomes in the third trimester. Human trophoblast cell line HTR8/SVneo was assigned as the negative control and miR-125a-5p mimics. QRT-PCR and Western blot were performed to identify the expressions of miR-125a-5p and vascular endothelial growth factor A (VEGFA). CCK8, flow cytometry, wound-healing and Transwell assays were used to analyze the effect of miR-125a-5p on HTR8/SVneo cell migration, proliferation, and cycle distribution. Tube formation was performed to estimate the angiogenesis ability of miR-125a-5p on HUVECs. In conclusion, miR-125a-5p expression in PE placental tissues was higher than in normal subjects, while the expression of VEGFA was lower in PE placental tissues. We then compared the miR-125a-5p mimics group with the negative control group and found that in the mimics group, the cell migration, proliferation and angiogenesis abilities were decreased, and more cells were arrested in the S stage. Our study systematically profiled the UCB exo-miRNA in normal and PE pregnant women and demonstrated that dysregulation of miR-125a-5p might affect HTR8/SVneo cell proliferation and migration and inhibit angiogenesis by regulating VEGFA, indicating that miR-125a-5p is involved in the progression of PE.

miRNA Profiles in Extracellular Vesicles From Serum Early in Pregnancies Complicated by Gestational Diabetes Mellitus

CONTEXT

Underlying mechanisms leading to gestational diabetes mellitus (GDM) are still under investigation, and it is unclear whether the placenta plays a role in triggering glucose intolerance or if its functions are modified in response to the hyperglycemia. Circulating miRNAs are involved in placental development and function and are encapsulated in extracellular vesicles (EVs).

OBJECTIVE

To compare differential expression of miRNAs in circulating EVs in pregnancies complicated by GDM vs controls.

METHODS

This was a case-control study nested in a prospective pregnancy cohort including 23 women with GDM and 46 matched controls. The presence of serum EVs in early pregnancy was validated by transmission electron microscopy. Placental dimensions were assessed at 11 to 13 weeks of gestation. Differential expression of 17 miRNAs encapsulated in EVs (miR‒122-5p, miR‒132-3p, miR-1323, miR‒182-3p, miR‒210-3p, miR‒29a-3p, miR‒29b-3p, miR‒342-3p, miR‒517-5p, miR‒517a-3p, miR‒518b, miR-520h, miR‒525-5p, miR‒136-5p, miR‒342-3p, miR‒376c-5p, and miR‒494-3p) was assessed using quantitative reverse transcription PCR.

RESULTS

EVs were present in the early phase of placentation (6 to 15 weeks of gestation) in both cases and controls. No differences were observed for placental dimensions and estimated placental volume between GDM and control groups. Ten miRNAs (miR‒122-5p; miR‒132-3p; miR‒1323; miR‒136-5p; miR‒182-3p; miR‒210-3p; miR‒29a-3p; miR‒29b-3p; miR‒342-3p, and miR-520h) showed significantly higher levels in GDM cases than in controls (P ≤ 0.05). Bioinformatics analysis showed that these miRNAs are involved in trophoblast proliferation/differentiation as well as in insulin secretion/regulation and glucose transport in pregnant women.

CONCLUSION

The miRNA content of blood EVs may be a promising avenue for studying the early effect of impaired glucose metabolism on placental development.

MicroRNAs in Uteroplacental Vascular Dysfunction

Pregnancy complications of preeclampsia and intrauterine growth restriction (IUGR) are major causes of maternal and perinatal/neonatal morbidity and mortality. Although their etiologies remain elusive, it is generally accepted that they are secondary to placental insufficiency conferred by both failure in spiral artery remodeling and uteroplacental vascular malfunction. MicroRNAs (miRNAs) are small no-coding RNA molecules that regulate gene expression at the post-transcriptional level. Increasing evidence suggests that miRNAs participate in virtually all biological processes and are involved in numerous human diseases. Differentially expressed miRNAs in the placenta are typical features of both preeclampsia and IUGR. Dysregulated miRNAs target genes of various signaling pathways in uteroplacental tissues, contributing to the development of both complications. In this review, we provide an overview of how aberrant miRNA expression in preeclampsia and IUGR impacts the expression of genes involved in trophoblast invasion and uteroplacental vascular adaptation.

MicroRNAs: Small molecules with a large impact on pre-eclampsia

As critical mediators in biological processes, microRNAs (miRNAs) which are small and endogenous noncoding RNAs have been associated with disease progression, cell proliferation, and development. Pre-eclampsia (PE), a pregnancy-related disorder with no early markers or symptoms is recognized as the main reason for fetal and maternal mortality and morbidity in the initial steps or even during pregnancy, worldwide. Clinical symptoms usually appear in the third trimester of the pregnancy. Although numerous research have unraveled several aspects of placenta development abnormalities associated with abnormal trophoblastic invasion and angiogenesis modification, many questions about the PE pathogenesis remains unanswered. A large number of studies have shown the important role of miRNAs as potential biomarkers in the PE prognosis and diagnosis. Here, the latest investigations about the PE and placental miRNAs expression, as well as, the crucial role of miRNA molecules including miR-210 and miR-155 which are deregulated in patients with PE, will be argued.

PFOS Modulates Interactive Epigenetic Regulation in First-Trimester Human Trophoblast Cell Line HTR-8/SVneo

Organic compounds have been linked to adverse pregnancy complications. Perfluorooctanesulfonic acid (PFOS), a man-made fluorosurfactant and global pollutant, has been shown to induce oxidative stress in various cell types. Oxidative stress plays a key role in leading several placental diseases including preeclampsia (PE), gestational diabetes, spontaneous abortion, preterm labor, and intrauterine growth restriction. Recently, epigenetic regulation such as histone modifications, DNA methylation, and microRNAs (miRNAs), are shown to be associated with oxidative stress as well as pregnancy complications such as PE. However, whether PFOS exerts its detrimental effects in the placenta through epigenetics remains to be unveiled. Therefore, we aimed to investigate the effect of PFOS-induced reactive oxygen species (ROS) generation in first trimester human trophoblast cell line (HTR-8/SV_neo) and whether epigenetic regulation is involved in this process. When treated with a range of PFOS doses at 24 and 48 h, even at 10 μM, it significantly increased the ROS production and decreased gene and protein expression, respectively, of the DNA methyltransferases DNMT1 (p < 0.001; p < 0.05), DNMT3A (p < 0.001; p < 0.05), and DNMT3B (p < 0.01; p < 0.01) and the sirtuins, for example, SIRT1 (p < 0.001; p < 0.001) and SIRT3 (p < 0.001; p < 0.05), while reducing global DNA methylation (p < 0.01) and increasing protein lysine acetylation (p < 0.001) as compared to vehicle controls. Interestingly, PFOS (10 μM) significantly increased miR29-b (p < 0.01), which has been previously reported to be associated with PE. The observed epigenetic effects were shown to be dependent on the expression of miR-29b, as knockdown of miR-29b significantly alters the gene and protein expression of DNMT1, DNMT3A, DNMT3B, SIRT1, and SIRT3 and ROS production as well as global DNA methylation and protein acetylation. This study provides for the first time a novel insight into PFOS-induced ROS generation via regulation of sets of the interactive epigenetic circuit in the placenta, which may lead to pregnancy complications.

lncRNA TUG1 modulates proliferation, apoptosis, invasion, and angiogenesis via targeting miR-29b in trophoblast cells

BACKGROUND

Pre-eclampsia (PE) is regarded as the leading cause of maternal and neonatal morbidity and mortality. Nevertheless, the potential mechanism for the regulation of trophoblast behaviors and the pathogenesis of PE remain largely elusive. Recently, accumulating evidence emphasized that aberrant expression of long non-coding RNAs (lncRNAs) functions as imperative regulators in human diseases, including PE. Thus, identifying PE-related specific lncRNAs to uncover the underlying molecular mechanism is of much significance. However, the functional roles and underlying mechanisms of lncRNAs in PE progression remain unclear.

METHOD

Placenta tissues obtained from patients with PE and healthy pregnant women were performed to measure TUG1 expression by qRT-PCR analysis. Transient transfections were conducted to alter TUG1 expression. Cell Counting Kit-8 (CCK-8) and flow cytometry assays were carried out to assess cell proliferation and apoptosis, respectively. Transwell and tube formation assays were performed to measure the capacity of cell invasion and angiogenesis. Moreover, the luciferase reporter assay was subjected to verify the binding relationship between TUG1 and miR-29b. Western blot analysis was performed to detect the expression of key proteins in the PI3K/AKT and ERK pathway.

RESULTS

Here, we identified a lncRNA, TUG1, which was notably decreased in placental samples of PE patients. Functional experiments of loss- or gain-of-function assays also verified that ectopic expression of TUG1 promoted cell proliferation, invasion, and angiogenesis, but negatively regulated cell apoptosis, whereas TUG1 inhibition presented the opposite effects. Furthermore, mechanistic researches revealed that TUG1 could act as a molecular sponge for miR-29b, thus regulating MCL1, VEGFA, and MMP2 to modulate PE development.

CONCLUSIONS

Taken together, our findings demonstrated that TUG1 exerts as a critical role in PE progression, which might furnish a novel therapeutic marker for PE treatment.

Effect of microRNA-29b on proliferation, migration, and invasion of endometrial cancer cells

Objective

Aberrant expression of microRNAs is a key regulator of tumorigenesis and progression in endometrial cancer. We assessed the effect of microRNA-29b (miR-29b) on proliferation, chemosensitivity, migration, and invasion of endometrial cancer cells.

Methods

The proliferation of endometrial cancer cells was examined by water-soluble tetrazolium (WST)-1 assay. The effects of miR-29b on migration and invasion were evaluated by transwell migration and Matrigel invasion assays. Western blotting was used to assess protein expression levels after altered expression of miR-29b. The effect of miR-29b on cisplatin-induced apoptosis was examined by Caspase-Glo 3/7 assay.

Results

miR-29b inhibited proliferation and decreased migration and invasion of endometrial cancer cells. It also enhanced the sensitivity of endometrial cancer cells to cisplatin and increased cisplatin-induced apoptosis by regulating expression of BAX and Bcl-2. Moreover, miR-29b changed the expression level of phosphatase and tensin homolog (PTEN) and p-AKT by directly binding to the 3′ untranslated region of PTEN.

Conclusion

miR-29b played important roles in proliferation and progression in endometrial cancer cells by direct regulation of PTEN. It might be used as a biomarker to predict chemotherapy response and prognosis in endometrial cancer.

miR-29b in regulating blood pressure and cardiac function in the rat model of hypertension

The possibility of micro ribonucleic acid-29b (miR-29b) regulating blood pressure and cardiac function in the rat model of hypertension was investigated. Sixty rat models of hypertension were established and randomly divided into the lentivirus group (n=20), the negative lentivirus group (n=20) and the control group (n=20). Rats in the lentivirus group were injected with the recombinant lentivirus, and those in the negative lentivirus and control groups were injected with the negative control virus and infection enhancement solution, respectively. The systolic pressure of rats was monitored using the tail-cuff method, and changes in the cardiac function of rats were evaluated via high-frequency ultrasound. At 3 weeks after virus infection, rats were weighed and sacrificed, the heart was taken and the left ventricular mass index was calculated. Moreover, the expression of miR-29b in myocardial tissues was detected via reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The systolic pressure in the lentivirus group was significantly decreased compared with those in the negative lentivirus and control groups (P<0.05). In the lentivirus group, the systolic pressure was significantly reduced after virus transfection (P<0.05), and there were also statistically significant differences in ultrasonic measurement indexes (LVPWT, IVST, LVEDD and LVESD) (P<0.05). LVPWT was remarkably decreased at 5 weeks and 6 weeks compared with that in the previous week, and it was lower than those in the other two groups (all P<0.05). After virus transfection, IVST in the lentivirus group showed a decreasing trend, which was obviously lower than those in the other two groups (P<0.05). After virus transfection, LVEDD in the lentivirus group increased gradually, and was higher than that in the other two groups. The expression of miR-29b was upregulated in the lentivirus group compared with those in the other two groups (P<0.05). The overexpression of miR-29b can reduce the blood pressure and significantly improve the cardiac function of hypertension rats.

Downregulation of MicroRNA-125a in Placenta Accreta Spectrum Disorders Contributes Antiapoptosis of Implantation Site Intermediate Trophoblasts by Targeting MCL1

The typical hallmark of placenta accreta spectrum (PAS) disorders is increased implantation site intermediate trophoblast (ISIT) cell numbers. However, the extent of trophoblast proliferation and apoptosis have not been found to differ from those of normal placentation. MicroRNA-125a (miR-125a) induces apoptosis in colon cancer cell by targeting myeloid cell leukemia-1 gene (MCL1). We aimed to investigate the influence of miR-125a on ISIT cells in PAS disorders in 15 patients (self-paired trials) with placenta previa and PAS disorders. Expression of miR-125a and MCL1 were measured in villous trophoblasts and basal plate myometrial fibers from creta site and adjacent noncreta tissues by real-time quantitative polymerase chain reaction, and expression of the MCL1 protein was assayed by Western blotting. Flow-cytometry was used to examine the effect of miR-125a overexpression on apoptosis in vitro in HTR-8/SVneo cells, and luciferase activity assays was used to confirm miR-125a targeting of MCL1. In vivo, the expression levels of miR-125a was significantly lower in creta versus noncreta tissues, and the expression of MCL1 was upregulated; moreover, immunohistochemistry showed that the increased ISIT cells in the creta were positive for MCL1 protein. MCL1 was downregulated in the miR-125a-overexpressing HTR-8/SVneo cells in vitro, and overexpression of miR-125a-induced apoptosis in the HTR-8/SVneo trophoblast line. Finally, luciferase activity assays confirmed that miR-125a directly target the 3' untranslated region of MCL1 in the 293T cell line. In conclusion, downregulation of MCL1-targeting miR-125a exerts an antiapoptotic effect on ISIT cells in PAS disorders.

MicroRNAs in Preeclampsia

Preeclampsia (PE) continues to represent a worldwide problem and challenge for both clinicians and laboratory-based doctors. Despite many efforts, the knowledge acquired regarding its pathogenesis and pathophysiology does not allow us to treat it efficiently. It is not possible to arrest its progressive nature, and the available therapies are limited to symptomatic treatment. Furthermore, both the diagnosis and prognosis are frequently uncertain, whilst the ability to predict its occurrence is very limited. MicroRNAs are small non-coding RNAs discovered two decades ago, and present great interest given their ability to regulate almost every aspect of the cell function. A lot of evidence regarding the role of miRNAs in pre-eclampsia has been accumulated in the last 10 years. Differentially expressed miRNAs are characteristic of both mild and severe PE. In many cases they target signaling pathway-related genes that result in altered processes which are directly involved in PE. Immune system, angiogenesis and trophoblast proliferation and invasion, all fundamental aspects of placentation, are controlled in various degrees by miRNAs which are up- or downregulated. Finally, miRNAs represent a potential therapeutic target and a diagnostic tool.

Roles of miR-210 in the pathogenesis of pre-eclampsia

INTRODUCTION

This study aimed to explore the bio-function of miR-210 in the pathogenesis of pre-eclampsia and provide new insights into the diagnosis and treatment of pre-eclampsia.

MATERIAL AND METHODS

A JAR cell line cultured in standard or hypoxic conditions was used in this study. Expression levels of miR-210 and PTPN2 were determined using real-time polymerase chain reaction (RT-PCR). Protein and phosphorylation levels were assessed using western blotting. Proliferation of JAR cells was evaluated using MTT assay. Migration and invasion were measured using transwell assay.

RESULTS

Expression of miR-210 increased significantly in a time-dependent manner after hypoxia treatment within 36 h (p < 0.05). miR-210 inhibitor significantly decreased the cell proliferation, migration, and invasion (p < 0.05), while miR-210 mimic reversed these findings (p < 0.05). Hypoxia significantly suppressed the expression of PTPN2; however, this elevation was abolished by miR-210 inhibitor (p < 0.05). Inhibition of PTPN2 or hypoxia significantly increased the proliferation, migration, and invasion of JAR cells, while miR-210 inhibitor significantly reversed these changes (p < 0.05). The phosphorylation levels of PDGFR, Akt, and Erk were markedly upregulated by hypoxia or si-PTPN2, but this effect was abolished by miR-210 inhibitor (p < 0.05).

CONCLUSIONS

miR-210 can promote proliferation, migration, and invasion via downregulating PTPN2 in the PDGFR-Akt pathway.

Kinetics of the chromosome 14 microRNA cluster ortholog and its potential role during placental development in the pregnant mare

Background

The human chromosome 14 microRNA cluster (C14MC) is a conserved microRNA (miRNA) cluster across eutherian mammals, reported to play an important role in placental development. However, the expression kinetics and function of this cluster in the mammalian placenta are poorly understood. Here, we evaluated the expression kinetics of the equine C24MC, ortholog to the human C14MC, in the chorioallantoic membrane during the course of gestation.

Results

We demonstrated that C24MC-associated miRNAs presented a higher expression level during early stages of pregnancy, followed by a decline later in gestation. Evaluation of one member of C24MC (miR-409-3p) by in situ hybridization demonstrated that its cellular localization predominantly involved the chorion and allantoic epithelium and vascular endothelium. Additionally, expression of predicted target transcripts for C24MC-associated miRNAs was evaluated by RNA sequencing. Expression analysis of a subset of predicted mRNA targets showed a negative correlation with C24MC-associated miRNAs expression levels during gestation, suggesting the reciprocal control of these target transcripts by this miRNA cluster. Predicted functional analysis of these target mRNAs indicated enrichment of biological pathways related to embryonic development, endothelial cell migration and angiogenesis. Expression patterns of selected target mRNAs involved in angiogenesis were confirmed by RT-qPCR.

Conclusion

This is the first report evaluating C24MC kinetics during pregnancy. The findings presented herein suggest that the C24MC may modulate angiogenic transcriptional profiles during placental development in the horse.

Electronic supplementary material

The online version of this article (10.1186/s12864-018-5341-2) contains supplementary material, which is available to authorized users.

MicroRNA-423-5p inhibits the progression of trophoblast cells via targeting IGF2BP1

INTRODUCTION

Preeclampsia (PE) is one of the leading causes of maternal and fetal mortality globally. The imbalance of trophoblast homeostasis is closely linked with the pathogenesis of PE. MicroRNA-423-5p (miR-423-5p) has been reported to be abnormally expressed in placenta and blood plasma of pregnant women with PE. In the present study, miR-423-5p expression in blood plasma of pregnant women with PE and healthy pregnant women was detected. Also, the roles and molecular mechanisms of miR-423-5p in the development of trophoblast cells were further investigated.

METHODS

Expression of miR-423-5p and insulin like growth factor 2 mRNA binding protein 1 (IGF2BP1) mRNA was detected by RT-qPCR assay. Protein expression of IGF2BP1, Bcl-2 and Bax was determined using western blot assay. Cell migratory and invasive capacities were assessed by transwell migration and invasion assay. Cell apoptotic rate was determined using flow cytometry via the double-staining of Annexin V-FITC/Propidium Iodide. The interaction between miR-423-5p and IGF2BP1 was demonstrated by bioinformatics analysis and luciferase reporter assay.

RESULTS

MiR-423-5p was highly expressed in blood plasma of pregnant women with PE. MiR-423-5p inhibited migration, invasion and proliferation as well as induced apoptosis in HTR-8/SVneo cells. Further investigation revealed that IGF2BP1 was a target of miR-423-5p. Moreover, IGF2BP1 overexpression promoted migration, invasion and proliferation, suppressed apoptosis, and weakened miR-423-5p function in HTR-8/SVneo cells.

DISCUSSION

MiR-423-5p inhibited migration, invasion and proliferation as well as induced apoptosis by targeting IGF2BP1 in HTR-8/SVneo cells, presenting a novel molecular basis implicated in PE pathogenesis.

MicroRNA-431 affects trophoblast migration and invasion by targeting ZEB1 in preeclampsia

BACKGROUND

Preeclampsia (PE) is a pregnancy complication that is characterized by higher blood pressure, together with higher protein quantity presence in the urine, which occurs after 20 weeks of gestation leading to severity of adverse maternal and fetal consequences. Some special microRNAs (miRNAs) expressed in placentas may be related to the occurrence of PE. Researchers have found that the expression of miR-431 in PE placentas was increased if compared with normal placentas; however, the effect and mechanism of miR-431 in PE are still unknown.

METHODS

In this study, we compared the expression levels of miR-431 and its putative target gene Zinc finger E-box-binding homeobox 1 (ZEB1) in 30 PE placentas and 30 normal placenta tissues. The effects of miR-431 and ZEB1 were verified by CCK-8 assay, transwell migration and invasion assay, cell cycle distribution assay and apoptosis assay in HTR-8/SVneo cells transfected with miR-431 mimic, siR-ZEB1 and their negative controls.

RESULTS

Results revealed that miR-431 was markedly added, while the mRNA and protein expressions of ZEB1 were decreased in PE placentas. The functional tests showed over-expression of miR-431 suppressed ZEB1 expression and decreased the migration and invasive capacity of trophoblast cells. MiR-431 overexpression induced apoptosis of HTR-8/SVneo cells, but it had no significant effect on cell proliferation and the distribution of cell cycle. In addition, siR-ZEB1 simulated the roles of miR-431 mimic. We found that miR-431 mimic and siR-ZEB1 reduced the epithelial-mesenchymal transition (EMT) with added E-cadherin expression and reduced vimentin expression in the cell line.

CONCLUSIONS

In conclusion, we found that miR-431 inhibited the migration and invasion of trophoblastic cells by targeting ZEB1, which might give rise to the onset of PE.

Role of mesenchymal stem cells exosomes derived microRNAs; miR-136, miR-494 and miR-495 in pre-eclampsia diagnosis and evaluation

BACKGROUND

Pre-eclampsia (PE) is one of the most threatening pregnancy complications. So far neither a secure, competent therapy for PE nor effective biomarkers for a premature discovery has been achieved. However, currently, the use of released microRNAs (miRNAs) as potential biomarkers and therapy targets for various diseases is the dominating area of research. The aim of our study was to identify miRNAs 136, 494 and 495 genes expression in exosomes of peripheral blood compared to umbilical cord mesenchymal stem cells (UCMSCs) conditioned media released exososomes in patients with PE, as valuable markers for PE early prediction.

METHODS

Blood samples were collected from 100 patients with PE and 100 control with normal pregnancies. Thirty fresh umbilical cord samples of women with healthy pregnancies (n = 15) and PE patients (n = 15) were retrieved during caesarean deliveries and UCMSCs were isolated from Wharton jelly. The expression of miRNAs 136, 494 and 495 in exosomes of peripheral blood and UCMSCs conditioned media was measured using quantitative real-time PCR method. Unpaired t-test, Pearson correlation test and Receiver operator characteristic (ROC) analysis were used for data analysis.

RESULTS

Our study revealed a significantly higher expression levels of miRNAs 136, 494 and 495 in exosomes of peripheral blood and matched with UCMSCs released exosomes from patients with PE compared to normal pregnancies (p = 0.000). In peripheral blood of PE, they were 6.4, 3.9 and 2.1 folds higher, respectively. ROC analysis revealed that the sensitivity and specificity values of miRNA-136 were 95% and 100%, respectively, with a cut-off value of 2.55. The sensitivity and specificity values of miRNA-494 were 86% and 95%, respectively, with a cut-off value of 0.47. The sensitivity and specificity values of miRNA-495 were 90% and 83%, respectively, with a cut-off value of 1.287.

CONCLUSION

Our findings suggest that exosomes derived miRNA-136, miRNA-494 and miRNA-495 could be promising circulating biomarkers in early detection of PE. Furthermore, UCMSCs released exosomes miRNA-136, miRNA-494 and miRNA-495 genes expression confirmed peripheral blood results analysis.

Roles of microRNAs in preeclampsia

Preeclampsia (PE) is a complex disorder that is characterized by hypertension and proteinuria after the 20th week of pregnancy, and it causes most neonatal morbidity and perinatal mortality. Most studies suggest that placental dysfunction is the main cause of PE. However, genetic factors, immune factors, and systemic inflammation are also related to the pathophysiology of this syndrome. Thus far, the exact pathogenesis of PE is not yet fully understood, and intense research efforts are focused on PE to elucidate the pathophysiological mechanisms. MicroRNAs (miRNAs) refer to small single-stranded and noncoding molecules that can negatively regulate gene expression, and miRNA regulatory networks play an important role in diverse pathological processes. Many studies have confirmed deregulated miRNA in pregnant patients with PE, and the function and mechanism of these differentially expressed miRNA are gradually being revealed. In this review, we summarize the current research about miRNA involved in PE, including placenta-specific miRNA, their predictive value, and their function in the development of PE. This review will provide fundamental evidence of miRNA in PE, and further studies are necessary to explore the roles of miRNA in the early diagnosis and treatment of PE.