Association of Circulating miRNA Expression with Preeclampsia, Its Onset, and Severity

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.

Streamlined Analysis of Maternal Plasma Indicates Small Extracellular Vesicles are Significantly Elevated in Early-Onset Preeclampsia

Preeclampsia (PE) is a leading cause of maternal and fetal mortality and morbidity. While placental dysfunction is a core underlying issue, the pathogenesis of this disorder is thought to differ between early-onset (EOPE) and late-onset (LOPE) subtypes. As recent reports suggest that small extracellular vesicles (sEVs) contribute to the development of PE, we have compared systemic sEV concentrations between normotensive, EOPE, and LOPE pregnancies. To circumvent lengthy isolation techniques and intermediate filtration steps, a streamlined approach was developed to evaluate circulating plasma sEVs from maternal plasma. Polymer-based precipitation and purification were used to isolate total systemic circulating maternal sEVs, free from bias toward specific surface marker expression or extensive subpurification. Immediate Nanoparticle Tracking Analysis (NTA) of freshly isolated sEV samples afforded a comprehensive analysis that can be completed within hours, avoiding confounding freeze-thaw effects of particle aggregation and degradation.Rather than exosomal subpopulations, our findings indicate a significant elevation in the total number of circulating maternal sEVs in patients with EOPE. This streamlined approach also preserves sEV-bound protein and microRNA (miRNA) that can be used for potential biomarker analysis. This study is one of the first to demonstrate that maternal plasma sEVs harbor full-length hypoxia inducible factor 1 alpha (HIF-1α) protein, with EOPE sEVs carrying higher levels of HIF-1α compared to control sEVs. The detection of HIF-1α and its direct signaling partner microRNA-210 (miR-210) within systemic maternal sEVs lays the groundwork for identifying how sEV signaling contributes to the development of preeclampsia. When taken together, our quantitative and qualitative results provide compelling evidence to support the translational potential of streamlined sEV analysis for future use in the clinical management of patients with EOPE.

Association between expression levels of p53, miRNA-21, and lncRNA-TCL6 and the risk of preeclampsia in pregnant women

BACKGROUND

Preeclampsia is a hypertensive pregnancy-related disorder. The etiology of preeclampsia is still not fully elucidated. Genetic factors are suggested to play a vital role.

AIM

The association between p53, miRNA-21, and lncRNA-TCL6 expression levels and the risk of preeclampsia and its onset and severity in pregnant women was evaluated.

METHOD

Expression levels of the analyzed RNAs were assessed in the serum samples from 75 preeclamptic pregnant women and 75 volunteer pregnant women with an uncomplicated pregnancy.

RESULTS

Cases showed upregulated p53, lnc-TCL6, and downregulated miRNA-21. P53 expression and preeclampsia severity were substantially correlated, while miRNA-21 and lnc-TCL6 were not. None of them was associated with preeclampsia onset. In diagnosing preeclampsia, p53 had the best sensitivity (98.67 %), followed by miRNA-21 (97.33 %) and lnc-TCL6 (92 %). P53 had the highest sensitivity (68.42 %) for distinguishing mild from severe cases. Lnc-TCL6 exhibited 52.63 % sensitivity, while miRNA-21 had 52.63 % sensitivity. Finally, for discriminating early and late-onset cases, miRNA-21 demonstrated the highest sensitivity (66 %), followed by p53 (62 %) and lnc-TCL6 (54 %). P53 expression was inversely correlated with proteinuria. Parity, TLC, platelet count, AST, and ALT were positively correlated, while lnc-TCL6 expression was negatively correlated with miRNA-21 expression. However, parity negatively correlated with lnc-TCL6 expression.

CONCLUSION

P53, miRNA-21, and lnc-TCL6 were dysregulated in preeclampsia compared to normal pregnancy, highlighting the role of apoptosis in its development. P53 can be a prognostic marker for preeclampsia, discriminating between mild and severe cases.

Circulating miRNAs and Preeclampsia: From Implantation to Epigenetics

In this review, we comprehensively present the literature on circulating microRNAs (miRNAs) associated with preeclampsia, a pregnancy-specific disease considered the primary reason for maternal and fetal mortality and morbidity. miRNAs are single-stranded non-coding RNAs, 20-24 nt long, which control mRNA expression. Changes in miRNA expression can induce a variation in the relative mRNA level and influence cellular homeostasis, and the strong presence of miRNAs in all body fluids has made them useful biomarkers of several diseases. Preeclampsia is a multifactorial disease, but the etiopathogenesis remains unclear. The functions of trophoblasts, including differentiation, proliferation, migration, invasion and apoptosis, are essential for a successful pregnancy. During the early stages of placental development, trophoblasts are strictly regulated by several molecular pathways; however, an imbalance in these molecular pathways can lead to severe placental lesions and pregnancy complications. We then discuss the role of miRNAs in trophoblast invasion and in the pathogenesis, diagnosis and prediction of preeclampsia. We also discuss the potential role of miRNAs from an epigenetic perspective with possible future therapeutic implications.

Increased expression level of Dicer in placenta is associated with the early onset of preeclampsia

This is a Letter to the Editor and does not have an abstract.

MicroRNA-206 Contributes to the Progression of Preeclampsia by Suppressing the Viability and Mobility of Trophocytes via the Inhibition of AGTR1

The development of preeclampsia (PE) is associated with the impaired trophoblast motility. MicroRNAs (miRs) contribute to the modulation of trophoblast invasion. In the current study, the role of miR-206/AGTR1 in the TNF-alpha-induced invasion defect of trophoblasts was explored. The levels of miR-206 and ATGR1 in clinical placenta tissues were investigated. Trophoblasts were treated with TNF-alpha, and the levels of miR-206 and ATGR1 were modulated. Changes in cell viability, invasion, and inflammation in trophoblasts were detected. The level of miR-206 was induced, while the level of AGTR1 was suppressed in placenta tissues. In in vitro assays, TNF-alpha suppressed viability, induced inflammatory response, inhibited invasion, upregulated miR-206, and down-regulated AGTR1. The inhibited expression of miR-206 or the overexpression of AGTR1 counteracted the effects of TNF-alpha, indicating the key role of the miR-206/AGTR1 in progression of PE. Collectively, miR-206 suppressed viability, induced inflammatory response, and decreased invasion of trophoblasts by inhibiting AGTR1.

The Ratio of Cysteine-Rich Angiogenic Inducer 61 to MicroRNA -155 Expression as a Preeclampsia Diagnostic Marker and Predictor of Its Severity

Background

Preeclampsia (PE) is a multisystem pregnancy disorder that increases maternal-perinatal morbidity and mortality significantly. MicroRNA-155 (miR-155) overexpression in the sera of pregnant women has been linked to preeclampsia. Researchers discovered that miR-155 acts during pregnancy by down-regulating and reducing the cysteine-rich angiogenic inducer 61 (CYR61), which causes local ischemia as well as oxidative stress.

Methods

The level of miR-155 expression in all serum samples was quantified using real-time polymerase chain reaction (RT-PCR), and serum CYR61 was measured using enzyme-linked immunosorbent assays. Together with the Cyr-61/miR-155 ratio, they were evaluated as biomarkers for PE pathogenesis and severity prediction.

Results

MiR-155 expression, serum CYR61 levels, and Cyr-61/miR-155 ratios were all significantly higher in PE patients compared to the control group. Serum CYR61 levels and the Cyr-61/miR-155 ratio differed significantly between mild and severe PE patients.

Conclusions

MiR-155 expression, serum CYR61 levels, and Cyr-61/miR-155 may serve as biomarkers for PE pathogenesis and severity prediction.

MicroRNAs: key regulators of the trophoblast function in pregnancy disorders

The placenta is essential for a successful pregnancy and healthy intrauterine development in mammals. During human pregnancy, the growth and development of the placenta are inseparable from the rapid proliferation, invasion, and migration of trophoblast cells. Previous reports have shown that the occurrence of many pregnancy disorders may be closely related to the dysfunction of trophoblasts. However, the function regulation of human trophoblast cells in the placenta is poorly understood. Therefore, studying the factors that regulate the function of trophoblast cells is necessary. MicroRNAs (miRNAs) are small, non-coding, single-stranded RNA molecules. Increasing evidence suggests that miRNAs play a crucial role in regulating trophoblast functions. This review outlines the role of miRNAs in regulating the function of trophoblast cells and several common signaling pathways related to miRNA regulation in pregnancy disorders.

A blood-based miRNA signature for early non-invasive diagnosis of preeclampsia

BACKGROUND

Preeclampsia (PE) is a multisystemic maternal syndrome with substantial maternal and fetal morbidity and mortality. Currently, there is no clinically viable non-invasive biomarker assay for early detection, thus limiting the effective prevention and therapeutic strategies for PE.

METHODS

We conducted a discovery-training-validation three-phase retrospective and prospective study with cross-platform and multicenter cohorts. The initial biomarkers were discovered and verified in tissue specimens by small RNA sequencing and qRT-PCR. A miRNA signature (miR2PE-score) was developed using Firth's bias-reduced logistic regression analysis and subsequently validated in two independent multinational retrospective cohorts and two prospective plasma cohorts.

RESULTS

We initially identified five PE-associated differentially expressed miRNAs from miRNA sequencing data and subsequently validated two miRNAs (miR-196b-5p and miR-584-5p) as robust biomarkers by association analysis with clinical characteristics and qRT-PCR in tissue specimens in the discovery phase. Using Firth's bias-reduced logistic regression analysis, we developed the miR2PE-score for the early detection of PE. The miR2PE-score showed a high diagnostic performance with an area under the receiver operating characteristic curve (AUROC) of 0.920, 0.848, 0.864, and 0.812 in training, internal, and two external validation cross-platform and multicenter cohorts, respectively. Finally, we demonstrated the non-invasive diagnostic performance of the miR2PE-score in two prospective plasma cohorts with AUROC of 0.933 and 0.787. Furthermore, the miR2PE-score revealed superior performance in non-invasive diagnosis compared with previously published miRNA biomarkers.

CONCLUSIONS

We developed and validated a novel and robust blood-based miRNA signature, which may serve as a promising clinically applicable non-invasive tool for the early detection of PE.

Circulating trophoblast numbers as a potential marker for pregnancy complications

OBJECTIVE

To explore the potential of circulating trophoblasts (TBs) as a non-invasive tool to assess placental health and predict obstetric complications.

METHODS

We retrospectively reviewed maternal characteristics and pregnancy outcomes of 369 women who enrolled in our original cell-based NIPT (cbNIPT) study. The number of circulating TBs recovered from the maternal blood samples was recorded and expressed as fetal cell concentration (FCC). We evaluated if FCC can be used to predict pregnancy outcomes such as hypertensive disorders of pregnancy (HDP), fetal growth restriction, placental abruption, preterm labor, and pregnancy loss.

RESULTS

Receiver operating characteristic (ROC) analysis was performed to find the best cut off value to classify FCC into a low and high FCC group, and this cut-off point was calculated as 11.1 cells per 100 ml of blood. The adjusted odds ratio (aOR) for the composite morbidity was significantly increased for the high FCC group at an aOR of 1.6.

CONCLUSION

Circulating TB have the potential of predicting obstetrical complications such as HDP. Future studies, with larger sample sizes, should focus on the study of these cells as a biomarker for placental health and a possible screening or diagnostic tool for fetal genetic conditions.

High miR-200a-3p expression has high diagnostic values for hypertensive disorders complicating pregnancy and predicts adverse pregnancy outcomes

BACKGROUND

Hypertensive disorders complicating pregnancy (HDCP) are various heterogeneous conditions. microRNA (miR)-200a-3p is involved in HDCP diagnosis. This study explored the effects of miR-200a-3p on HDCP patients.

METHODS

A total of 126 singleton HDCP patients including 50 cases of gestation hypertension (GH), 42 cases of mild preeclampsia (MP) and 34 cases of severe preeclampsia (SP), were enrolled as study subjects, and 50 normal pregnant women were selected as the control. Serum miR-200a-3p expression was detected and its efficacy in HDCP diagnosis and grading was evaluated. GH, MP and SP patients were allocated to high/low miR-200a-3p expression groups. The correlation between miR-200a-3p expression and general clinical indexes was analyzed. HDCP patients were allocated to high/low miR-200a-3p expression group and maternal and fetal outcomes were followed up. Effects of miR-200a-3p expression on adverse pregnancy outcome incidence were analyzed.

RESULTS

miR-200a-3p expression in the serum of HDCP patients was upregulated. The sensitivity and specificity of serum miR-200a-3p level > 1.201 were 87.3% and 96.0%, respectively. Serum miR-200a-3p level in GH, MP and SP patients was increased with the aggravation of the disease. The cut-off value and area under the curve (AUC) of miR-200a-3p for GH, MP and SP diagnosis were 1.145 and 0.9094 (82.0% sensitivity and 88.0% specificity), 1.541 and 0.8126 (73.8% sensitivity and 76.0% specificity), and 1.866 and 0.7367 (64.7% sensitivity and 76.2% specificity), respectively. Serum miR-200a-3p level was correlated with general clinical indexes, fetal birth weight, systolic to diastolic ratio, and fetal growth restriction incidence. High serum miR-200a-3p expression in HDCP patients was associated with increased adverse pregnancy outcomes.

CONCLUSION

High miR-200a-3p expression could help to diagnose HDCP, judge severity and was associated with increased adverse pregnancy outcomes.

Report of Exosomes Isolated from a Human Uterine Leiomyoma Cell Line and Their Impact on Endometrial Vascular Endothelial Cells

Uterine leiomyomas are the most common pelvic tumor in women of reproductive age; they cause irregular heavy menstrual bleeding leading to anemia and subsequent negative effects on quality of life. Exosomes have arisen as main players of disease progression in several illnesses, including a range of benign and malignant conditions; however, their role in leiomyomas' pathophysiology remains unknown. We investigated the effect of exosomes derived from human uterine leiomyoma tumor cells (HULM) and human myometrial cells (UTSM) on the behavior of human endometrial microvascular endothelial cells (HEMEC). HULM- and UTSM-derived exosomes were isolated and cocultured with HEMECs. Then, cell proliferation, mRNA expression, tube formation assay, and RNA-seq were performed. Treatment of HEMEC with HULM-derived exosomes increased cell proliferation by 60% compared to control untreated cells, upregulated C-MYC and VEGFA expression levels, and increased tube formation, length, and branching (markers of angiogenesis). Profiling of miRNA revealed that 84 miRNAs were significantly downregulated and 71 were upregulated in HULM-derived exosomes compared to UTSM-derived exosomes. These findings suggest that HULM-derived exosomes might have effects on HEMEC function, containing factors that enhance endometrial proliferation and angiogenesis, which may contribute to heavy menstrual bleeding. Further research on exosomes in uterine leiomyoma may identify possible novel biomarkers for treatment.

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.

The MEG3 lncRNA promotes trophoblastic cell growth and invasiveness in preeclampsia by acting as a sponge for miR-21, which regulates BMPR2 levels

Preeclampsia (PE) is one of the leading causes of maternal morbidity and mortality in pregnant women. This study aimed to investigate the potential impact and regulatory mechanisms of bone morphogenetic protein receptor 2 (BMPR2) on the progression of PE. We obtained placental tissues from pregnant women with PE and normal pregnant women, and the results showed that BMPR2 was expressed at low levels in the tissue from PE women. Genetic knockdown of BMPR2 increased the proliferation and invasion of cultured trophoblast cells, whereas its overexpression reduced these characteristics. Bioinformatics analysis and luciferase reporter gene assays confirmed that BMPR2 is a direct target of miR-21. Overexpression of a miR-21 inhibitor promoted the growth and invasiveness of trophoblast cells, whereas the opposite results were observed for the miR-21 mimic. Furthermore, miR-21 was sponged by the lncRNA MEG3, and shRNA inhibition of MEG3 reduced trophoblast cell growth and invasiveness. miR-21 was upregulated in the tissues from PE women, whereas MEG3 was downregulated, and the two were negatively correlated. Collectively, this study demonstrates that the lncRNA MEG3 acts as a sponge for miR-21, which regulates BMPR2 expression and promotes trophoblast cell proliferation and invasiveness, thereby preventing the development of PE. These findings provide novel insight into a targeted therapy that could be used to treat or prevent the development of PE.

Significance of Sex Differences in ncRNAs Expression and Function in Pregnancy and Related Complications

In the era of personalized medicine, fetal sex-specific research is of utmost importance for comprehending the mechanisms governing pregnancy and pregnancy-related complications. In recent times, noncoding RNAs (ncRNAs) have gained increasing attention as critical players in gene regulation and disease pathogenesis, and as candidate biomarkers in human diseases as well. Different types of ncRNAs, including microRNAs (miRNAs), piwi-interacting RNAs (piRNAs), long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs), participate in every step of pregnancy progression, although studies taking into consideration fetal sex as a central variable are still limited. To date, most of the available data have been obtained investigating sex-specific placental miRNA expression. Several studies revealed that miRNAs regulate the (patho)-physiological processes in a sexually dimorphic manner, ensuring normal fetal development, successful pregnancy, and susceptibility to diseases. Moreover, the observation that ncRNA profiles differ according to cells, tissues, and developmental stages of pregnancy, along with the complex interactions among different types of ncRNAs in regulating gene expression, strongly indicates that more studies are needed to understand the role of sex-specific ncRNA in pregnancy and associated disorders.