Human placental microRNAs and preeclampsia

Unraveling the role of microRNAs: potential biomarkers for gestational diabetes mellitus revealed through RNA sequencing analysis

BACKGROUND

Gestational diabetes mellitus (GDM) poses significant health risks for both mothers and children, contributing to long-term complications such as type 2 diabetes and cardiovascular disease. This study explores the potential of microRNAs (miRNAs) as biomarkers for GDM by analyzing peripheral blood samples from GDM patients.

METHOD

Ten samples, including peripheral blood from 5 GDM patients and 5 controls, were collected to perform the RNA sequencing analysis. Differentially expressed miRNAs were further validated by quantitative real-time polymerase chain reaction.

RESULTS

A total of 2287 miRNAs were identified, 229 of which showed differential expression. Validation by qRT-PCR confirmed significant up-regulation of miR-5193, miR-5003-3p, miR-3127-5p, novel-miR-96, miR-6734-5p, and miR-122-5p, while miR-10395-3p was down-regulated. Bioinformatics analyses revealed the involvement of these miRNAs in pathways associated with herpes simplex virus 1 infection.

CONCLUSION

This study provides insights into the differential expression of miRNAs in GDM patients and their potential roles in disease pathogenesis. It suggests that the differentially expressed miRNAs could serve as potential biomarkers for GDM, shedding light on the complex molecular mechanisms involved.

MicroRNA-125b regulates vitamin D resistance by targeting CYP24A1 in the progression of gestational diabetes mellitus

Vitamin D deficiency is prevalent in pregnancy and has been associated with increased occurrences of preeclampsia, cesarean delivery, neonatal bacterial vaginosis, and gestational diabetes. CYP24A1, recognized as a key factor in vitamin D metabolism homeostasis, encodes 24-hydroxylase responsible for converting 25(OH)D3 and 1,25(OH)2D3 into inactive metabolites. Recently, we have reported CYP24A1 overexpression in patients with gestational diabetes mellitus (GDM) and trophoblast cells exposed to hyperglycemia. In this study, we explored miRNA-mediated regulation of CYP24A1 in GDM progression, validating our findings through silencing experiments in a trophoblast cell line. In silico tools identified miR-125b-5p as a putative target of CYP24A1. Expression analysis revealed downregulation of miR-125b-5p in blood samples from early GDM and GDM compared to healthy pregnant women, positively correlating with vitamin D levels. Hyperglycemic exposure in human trophoblastic cell lines (BeWo) decreased miR-125b-5p expression, concomitant with an increase in CYP24A1. To confirm the regulatory role of miR-125b on CYP24A1, we transfected BeWo cells with antimiR-125b or miR-125b mimic. AntimiR-125b transfection heightened CYP24A1 levels, while miR-125b mimic overexpression resulted in decreased CYP24A1 expression. These findings establish miR-125b as a regulator of CYP24A1. To explore the influence of miR-125b on vitamin D metabolism, trophoblast cells overexpressing miR-125b were treated with 0.1 and 1 µM calcitriol. Hyperglycemic conditions exhibited a reduction in CYP24A1 levels. Collectively, our results indicate that miR-125b may regulate vitamin D metabolism by targeting CYP24A1, contributing to GDM progression. These findings may pave the way for understanding vitamin D resistance in concurrent GDM development and identifying novel miRNAs targeting CYP24A1.

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

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

Are Vascular Endothelium and Angiogenesis Effective MicroRNA Biomarkers Associated with the Prediction of Early-Onset Preeclampsia (EOPE) and Adverse Perinatal Outcomes?

MicroRNA is associated with angiogenesis, invasion, proliferation, and vascular endothelial remodeling of various diseases. We aimed to investigate serum MicroRNA (miRNA) levels in preeclampsia (PE) and to determine whether any changes in miRNA levels are useful in predicting early onset preeclampsia (EOPE) and adverse perinatal outcomes. A total of 89 pregnant patients were enrolled in this prospective case-control study (55 PE and 34 healthy controls). miR-17, miR-20a, miR-20b, miR126, miR155, miR-200, miR-222, and miR-210 levels were studied in maternal serum in preeclamptic pregnant women. Multiple logistic regression analyses analyzed the risk factors which are associated with EOPE and adverse maternal outcomes. The Real-time RT-PCR method was used to determine maternal serum miRNA levels. Serum miR-17, miR-20a, miR-20b, miR126, and miR-210 levels were significantly higher in PE than the control group (p < .001, p < .001, p < .001, p < .001 and p = .047 respectively). Increased miR-17, miR-20a, and miR-20b levels were independently associated with PE (OR: 0.642, 95%Cl: 0.486-0.846, p = .002; OR: 0.899, 95%Cl: 0.811-0.996, p = .042 and OR: 0.817, 95%Cl: 0.689-0.970, p = .021). Increased miR-17 and miR-126 levels were negatively correlated with serum EOPE in PE (r = -.313, p = .020), and increased miR-210 levels were significantly positively correlated with EOPE in PE (r = .285, p = .005). Increased expression of serum miR-17, miR-20a, miR-20b, miR126, and miR-210 were found to be associated with PE, also increased expression of miR-17, miR-20a, and miR-20b were to be predicted with PE, also increased maternal serum miR-17 and miR-126 expressions were negatively correlated and increased miR-210 expression was positively correlated with EOPE in PE women.

MicroRNA miR-27a as a possible regulator of anti-inflammatory macrophage phenotype in preeclamptic placenta

INTRODUCTION

The role of the TGFβ signaling pathway, an important cascade responsible for the anti-inflammatory polarization of macrophages, in the development of both early- and late-onset preeclampsia (eoPE and loPE), remains poorly understood. In this study, we examined the components of the TGFβ signaling cascade and macrophage markers within placental tissue in normal pregnancy and in PE.

METHODS

Patients with eoPE, loPE, and normal pregnancy were enrolled in the study (n = 10 in each group). Following techniques were used for the investigation: immunohistochemistry analysis, western blotting, qRT-PCR, isolation of monocytes by magnetic sorting, transfection, microRNA sequencing, and bioinformatic analysis.

RESULTS

We observed a significant decrease in the anti-inflammatory macrophage marker CD206 in the loPE group, alongside with a significant down-regulation of CD206 protein production in both eoPE and loPE groups. The level of CD68-positive cells and relative levels of CD163 and MARCO production were comparable across the groups. However, we identified a significant decrease in the TGFβ receptor 2 production and its gene expression in the PE group. Further analysis revealed a link between TGFBR2 and MRC1 (CD206) genes through a single miRNA, hsa-miR-27a-3p. Transfecting CD14-derived macrophages with the hsa-miR-27a-3p mimic significantly changed TGFBR2 production, indicating the potential role of this miRNA in regulating the TGFβ signaling pathway. We also revealed the up-regulation of hsa-miR-27a-5p and hsa-miR-27a-3p in the trophoblast BeWo b30 cell line under the severe hypoxia condition and the fact that TGFBR2 3' UTR could serve as a potential target for these miRNAs.

DISCUSSION

Our findings uncover a novel potential therapeutic target for managing patients with PE, significantly contributing to a deeper comprehension of the underlying mechanisms involved in the development of this pathology.

Circulating miRNAs in the first trimester and pregnancy complications: a systematic review

Most pregnancy complications originate with early placentation. MicroRNAs (miRNAs) may play an important role in placentation and function as biomarkers of future pregnancy complications. We summarized from the literature all first trimester circulating miRNAs associated with pregnancy complications of placental origin and further identified the miRNAs which have the most evidence as potential early biomarkers for pregnancy complications. We conducted a systematic review following PRISMA reporting guidelines (PROSPERO CRD42020183421). We identified all first trimester serum or plasma miRNAs associated with a pregnancy complication of placental origin (preeclampsia, intrauterine growth restriction (IUGR), gestational hypertension, preterm delivery) and the number of times those miRNAs were identified, as a measure of replication. Twenty-one studies examined 118 unique miRNAs, and 87 were associated with at least one pregnancy complication; preeclampsia was the most common. Seven miRNAs were significantly associated with a pregnancy complication in at least two studies: miR-125b, miR-518b, miR-628-3p, miR-365a-3p, miR-520h, miR-374a-5p, miR-191-5p. Few miRNAs were associated with more than one pregnancy complication: miR-518b and miR-520h with preeclampsia and gestational hypertension, miR-374a-5p and miR-191-5p with preterm birth and preeclampsia. Our systematic review suggests seven miRNAs as potential biomarkers of pregnancy complications. These complications are thought to originate with early placental defects and these miRNAs may also be biomarkers of placental pathology. First-trimester biomarkers of pregnancy complications can facilitate early detection and interventions.

Integration of circulating microRNAs and transcriptome signatures identifies early-pregnancy biomarkers of preeclampsia

BACKGROUND

MicroRNAs (miRNAs) have been implicated in the pathobiology of preeclampsia, a common hypertensive disorder of pregnancy. In a nested matched case-control cohort within the Vitamin D Antenatal Asthma Reduction Trial (VDAART), we previously identified peripheral blood mRNA signatures related to preeclampsia and vitamin D status (≤30 ng/mL) during gestation from 10 to 18 weeks, using differential expression analysis.

METHODS

Using quantitative PCR arrays, we conducted profiling of circulating miRNAs at 10-18 weeks of gestation in the same VDAART cohort to identify differentially expressed (DE) miRNAs associated with preeclampsia and vitamin D status. For the validation of the expression of circulating miRNA signatures in the placenta, the HTR-8/SVneo trophoblast cell line was used. Targets of circulating miRNA signatures in the preeclampsia mRNA signatures were identified by consensus ranking of miRNA-target prediction scores from four sources. The connected component of target signatures was identified by mapping to the protein-protein interaction (PPI) network and hub targets were determined. As experimental validation, we examined the gene and protein expression of IGF1R, one of the key hub genes, as a target of the DE miRNA, miR-182-5p, in response to a miR-182-5p mimic in HTR-8/SVneo cells.

RESULTS

Pregnant women with preeclampsia had 16 circulating DE miRNAs relative to normal pregnancy controls that were also DE under vitamin D insufficiency (9/16 = 56% upregulated, FDR < .05). Thirteen miRNAs (13/16 = 81.3%) were detected in HTR-8/SVneo cells. Overall, 16 DE miRNAs had 122 targets, of which 87 were unique. Network analysis demonstrated that the 32 targets of DE miRNA signatures created a connected subnetwork in the preeclampsia module with CXCL8, CXCL10, CD274, MMP9 and IGF1R having the highest connectivity and centrality degree. In an in vitro validation experiment, the introduction of an hsa-miR-182-5p mimic resulted in significant reduction of its target IGF1R gene and protein expression within HTR-8/SVneo cells.

CONCLUSIONS

The integration of the circulating DE miRNA and mRNA signatures associated preeclampsia added additional insights into the subclinical molecular signature of preeclampsia. Our systems and network biology approach revealed several biological pathways, including IGF-1, that may play a role in the early pathophysiology of preeclampsia. These pathways and signatures also denote potential biomarkers for the early stages of preeclampsia and suggest possible preventive measures.

USP8 targeted by Mir-874-3p promotes trophoblastic cell invasion by stabilizing the expression of ENaC on trophoblast membrane

The aim of this study was to investigate the role of ubiquitin-specific peptidase 8 (USP8) in human trophoblast cells and its molecular mechanism. Based on the GSE30186 dataset, USP8 was identified as a downregulated gene in pre-eclampsia (PE). Analysis of clinical samples also revealed that USP8 expression at both the mRNA and protein levels in placental tissue from patients with PE was significantly lower than that from healthy pregnant women. Plate clone formation, scratch-wound healing, Transwell, tubule formation, and western blot assays collectively revealed that USP8 overexpression promoted the proliferation, migration, invasion, and pro-angiogenesis function of trophoblast cells, while USP8 knockdown induced the opposite effects. Bioinformatics analysis and luciferase reporter assay results indicated that the 3' untranslated region of USP8 was targeted by miR-874-3p. USP8 expression in the placental tissue of patients with PE was significantly lower than that of healthy pregnant women. USP8 actively regulated the growth and invasion of human trophoblast cells and stabilized the epithelial sodium channel (ENaC) on the cell membrane. MiR-874 targeted USP8 in the trophoblast cells and upregulation of miR-874-3p resulted in a decrease in the proliferation, migration, invasion, and pro-angiogenesis ability of trophoblast cells. These results indicate that USP8 can reverse the above mentioned negative effects of miR-874-3p on trophoblast cells. USP8 targeted by miR-874-3p facilitates the invasion of trophoblastic cells by stabilizing the expression of the ENaC, which may be a possible therapeutic target for PE.

Inhibition of LAMP3 mediates the protective effect of vitamin D against hypoxia/reoxygenation in trophoblast cells

Inadequate invasion and excessive apoptosis of trophoblast cells are associated with the development of preeclampsia. Vitamin D deficiency in pregnant women may lead to an increased risk of preeclampsia. However, the underlying mechanisms by which vitamin D is effective in preventing preeclampsia are not fully understood. The objectives of this study were to investigate the role of lysosome-associated membrane glycoprotein 3 (LAMP3) in the pathogenesis of preeclampsia and to evaluate whether vitamin D supplementation would protect against the development of preeclampsia by regulating LAMP3 expression. Firstly, the mRNA and protein levels of LAMP3 were significantly upregulated in the placentas of preeclampsia patients compared to normal placentas, especially in trophoblast cells (a key component of the human placenta). In the hypoxia/reoxygenation (H/R)-exposed HTR-8/Svneo trophoblast cells, LAMP3 expression was also upregulated. H/R exposure repressed cell viability and invasion and increased apoptosis of trophoblast cells. siRNA-mediated knockdown of LAMP3 increased cell viability and invasion and suppressed apoptosis of H/R-exposed trophoblast cells. We further found that 1,25(OH)2D3 (the hormonally active form of vitamin D) treatment reduced LAMP3 expression in H/R exposed trophoblast cells. In addition, 1,25(OH)2D3 treatment promoted cell viability and invasion and inhibited apoptosis of H/R-exposed trophoblast cells. Notably, overexpression of LAMP3 abrogated the protective effect of 1,25(OH)2D3 on H/R-exposed trophoblast cells. Collectively, we demonstrated trophoblast cytoprotection by vitamin D, a process mediated via LAMP3.

Prediction of Early- and Late-Onset Pre-Eclampsia in the Preclinical Stage via Placenta-Specific Extracellular miRNA Profiling

Pre-eclampsia (PE) is one of the severe complications of pregnancy in 3-8% of all cases and is one of the leading causes of maternal and perinatal mortality. The fundamental role in the pathogenesis of PE is assigned to maternal and/or placental factors, whereby the combination and manifestation of which determines the time of onset of the clinical symptoms of PE (before or after 34 weeks of gestation) and their severity. It is known that the expression level of miRNAs, the regulators of signaling cascades in the cell, depends on gestational age. In the present study, we focused on the identification of the placenta-specific miRNAs that differentiate between early- and late-onset pre-eclampsia (ePE and lPE) throughout pregnancy, from the first to the third trimester. A total of 67 patients were analyzed using small RNA deep sequencing and real-time quantitative PCR, which resulted in a core list of miRNAs (let-7b-5p, let-7d-3p, let-7f-5p, let-7i-5p, miR-22-5p, miR-451a, miR-1246, miR-30e-5p, miR-20a-5p, miR-1307-3p, and miR-320e), which in certain combinations can predict ePE or lPE with 100% sensitivity and 84-100% specificity in the 1st trimester of pregnancy. According to the literature data, these miRNA predictors of PE control trophoblast proliferation, invasion, migration, syncytialization, the endoplasmic reticulum unfolded protein response, immune tolerance, angiogenesis, and vascular integrity. The simultaneous detection of let-7d-3p, miR-451a, and miR-1307-3p, resistant to the repeated freezing/thawing of blood serum samples, in combination with biochemical (b-hCG and PAPP-A) and ultrasound (UAPI) parameters, allowed us to develop a universal model for the prediction of ePE and lPE onset (FPR = 15.7% and FNR = 9.5%), which was validated using a test cohort of 48 patients and demonstrated false-positive results in 26.7% of cases and false negatives in 5.6% of cases. For comparison, the use of the generally accepted Astraia program in the analysis of the test cohort of patients led to worse results: FPR = 62.1% and FNR = 33.3%.

Epigenetic Mechanisms Involved in the Effects of Maternal Hyperhomocysteinemia on the Functional State of Placenta and Nervous System Plasticity in the Offspring

According to modern view, susceptibility to diseases, specifically to cognitive and neuropsychiatric disorders, can form during embryonic development. Adverse factors affecting mother during the pregnancy increase the risk of developing pathologies. Despite the association between elevated maternal blood homocysteine (Hcy) and fetal brain impairments, as well as cognitive deficits in the offspring, the role of brain plasticity in the development of these pathologies remains poorly studied. Here, we review the data on the negative impact of hyperhomocysteinemia (HHcy) on the neural plasticity, in particular, its possible influence on the offspring brain plasticity through epigenetic mechanisms, such as changes in intracellular methylation potential, activity of DNA methyltransferases, DNA methylation, histone modifications, and microRNA expression in brain cells. Since placenta plays a key role in the transport of nutrients and transmission of signals from mother to fetus, its dysfunction due to aberrant epigenetic regulation can affect the development of fetal CNS. The review also presents the data on the impact of maternal HHcy on the epigenetic regulation in the placenta. The data presented in the review are not only interesting from purely scientific point of view, but can help in understanding the role of HHcy and epigenetic mechanisms in the pathogenesis of diseases, such as pregnancy pathologies resulting in the delayed development of fetal brain, cognitive impairments in the offspring during childhood, and neuropsychiatric and neurodegenerative disorders later in life, as well as in the search for approaches for their prevention using neuroprotectors.

The Role of Placental Non-Coding RNAs in Adverse Pregnancy Outcomes

Non-coding RNAs (ncRNAs) are transcribed from the genome and do not encode proteins. In recent years, ncRNAs have attracted increasing attention as critical participants in gene regulation and disease pathogenesis. Different categories of ncRNAs, which mainly include microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), are involved in the progression of pregnancy, while abnormal expression of placental ncRNAs impacts the onset and development of adverse pregnancy outcomes (APOs). Therefore, we reviewed the current status of research on placental ncRNAs and APOs to further understand the regulatory mechanisms of placental ncRNAs, which provides a new perspective for treating and preventing related diseases.

Effect and mechanism of microRNA-515-5p in proliferation and apoptosis of trophoblast cells in preeclampsia via manipulating histone deacetylase 2

Preeclampsia (PE) refers to a pregnancy-specific disease that begins with the placenta. Differentially expressed microRNAs (miRs) are a feature of PE. This study tried to elicit the functional mechanism of miR-515-5p in trophoblast cell behaviors in PE. First, HTR-8/SVneo cells were transfected with miR-515-5p mimic or miR-515-5p inhibitor. Then, relative expression levels of miR-515-5p and histone deacetylase 2 (HDAC2) in HTR-8/SVneo cells were determined by reverse transcription-quantitative polymerase chain reaction. The potential binding site of miR-515-5p and HDAC2 was predicted on Targetscan and their binding relationship was verified via dual-luciferase assay. Proliferation, apoptosis, invasion, and migration of HTR-8/SVneo cells were assessed via cell counting kit-8, flow cytometry, Transwell, and wound healing assays, respectively. Protein levels of Cleaved caspase-3, Bcl-2, and Bax were determined via Western blot. Overexpressed miR-515-5p impeded proliferation and stimulated apoptosis of HTR-8/SVneo cells, and decreased levels of Cleaved caspase-3 and Bax and elevated Bcl-2, whilst opposite results were observed after miR-515-5p inhibition. miR-515-5p targeted HDAC2. Knockdown of HDAC2 annulled the promotional action of miR-515-5p inhibition on proliferative, invasive, and migratory abilities and its antiapoptotic action on HTR-8/SVneo cells. In brief, miR-515-5p affected the proliferation, apoptosis, invasion, and migration of HTR-8/SVneo cells by targeting HDAC2.

miR-515-5p suppresses trophoblast cell invasion and proliferation through XIAP regulation in preeclampsia

MicroRNAs (miRNAs) are non-coding small RNA molecules that can be secreted into the circulation and which exist in remarkably stable forms. Circulating miRNAs regulate numerous biological process and are aberrantly expressed in pathological conditions. Differentially expressed circulating miRNAs have received attention as potential biomarkers for many diseases. In this study, we revealed that miR-515-5p was significantly upregulated in maternal serum from preeclampsia patients in comparison to normal pregnant women. Bioinformatics prediction and a dual-luciferase reporter gene assay revealed that miR-515-5p directly targets the X-linked inhibitor of apoptosis protein (XIAP) 3'-untranslated region. In addition, the overexpression of miR-515-5p inhibited the proliferation and invasion of HTR-8/SVneo trophoblast cells. The decreased XIAP expression and reduced epithelial-mesenchymal transition (EMT) were observed in the preeclamptic placenta. Collectively, miR-515-5p may play critical roles in the pathogenesis of preeclampsia through suppression of XIAP, and serum miR-515-5p may act as a potential biomarker for preeclampsia.

Identification of altered miRNAs and their targets in placenta accreta

Placenta accreta spectrum (PAS) is one of the major causes of maternal morbidity and mortality worldwide with increasing incidence. PAS refers to a group of pathological conditions ranging from the abnormal attachment of the placenta to the uterus wall to its perforation and, in extreme cases, invasion into surrounding organs. Among them, placenta accreta is characterized by a direct adhesion of the villi to the myometrium without invasion and remains the most common diagnosis of PAS. Here, we identify the potential regulatory miRNA and target networks contributing to placenta accreta development. Using small RNA-Seq followed by RT-PCR confirmation, altered miRNA expression, including that of members of placenta-specific miRNA clusters (e.g., C19MC and C14MC), was identified in placenta accreta samples compared to normal placental tissues. In situ hybridization (ISH) revealed expression of altered miRNAs mostly in trophoblast but also in endothelial cells and this profile was similar among all evaluated degrees of PAS. Kyoto encyclopedia of genes and genomes (KEGG) analyses showed enriched pathways dysregulated in PAS associated with cell cycle regulation, inflammation, and invasion. mRNAs of genes associated with cell cycle and inflammation were downregulated in PAS. At the protein level, NF-κB was upregulated while PTEN was downregulated in placenta accreta tissue. The identified miRNAs and their targets are associated with signaling pathways relevant to controlling trophoblast function. Therefore, this study provides miRNA:mRNA associations that could be useful for understanding PAS onset and progression.

miR-372-3p promotes preeclampsia progression by regulating twist1

Preeclampsia (PE) is a common pregnancy-related disorder worldwide. PE is mainly characterized by the defective migration and invasion of trophoblast cells. MicroRNAs (miRs) have been reported to serve an important role in PE. The purpose of the study was to explore the pathogenesis and therapeutic targets of preeclampsia. In the present study, reverse transcription-quantitative PCR analysis revealed that the expression levels of miR-372-3p were upregulated in placental tissues from patients with PE. Notably, the expression levels of miR-372-3p were significantly upregulated in patients with early-onset PE compared with patients with late-onset PE. Moreover, in vitro analysis using wound healing, Transwell and western blotting assays demonstrated that miR-372-3p overexpression inhibited the migration, invasion and epithelial-mesenchymal transition (EMT) of HTR-8/SVneo trophoblast cells, respectively. Bioinformatics analysis and a dual luciferase reporter assay revealed that miR-372-3p is sponged by twist family bHLH transcription factor 1 (twist1). Rescue experiments found that miR-372-3p overexpression suppressed trophoblast cell migration, invasion and EMT by downregulating the expression of twist1. In conclusion, the present study revealed that high level of miR-372-3p may act as a factor to cause PE and may also be a potential novel therapeutic target for PE.

Global microRNA and protein expression in human term placenta

Introduction

Description of the global expression of microRNAs (miRNAs) and proteins in healthy human term placentas may increase our knowledge of molecular biological pathways that are important for normal fetal growth and development in term pregnancy. The aim of this study was to explore the global expression of miRNAs and proteins, and to point out functions of importance in healthy term placentas.

Materials and methods

Placental samples (n = 19) were identified in a local biobank. All samples were from uncomplicated term pregnancies with vaginal births and healthy, normal weight newborns. Next-generation sequencing and nano-scale liquid chromatographic tandem mass spectrometry were used to analyse miRNA and protein expression, respectively.

Results

A total of 895 mature miRNAs and 6,523 proteins were detected in the placentas, of which 123 miRNAs and 346 proteins were highly abundant. The miRNAs were in high degree mapped to chromosomes 19, 14, and X. Analysis of the highly abundant miRNAs and proteins showed several significantly predicted functions in common, including immune and inflammatory response, lipid metabolism and development of the nervous system.

Discussion

The predicted function inflammatory response may reflect normal vaginal delivery, while lipid metabolism and neurodevelopment may be important processes for the term fetus. The data presented in this study, with complete miRNA and protein findings, will enhance the knowledge base for future research in the field of placental function and pathology.

Decorin–induced, preeclampsia-associated microRNA-512-3p restrains extravillous trophoblast functions by targeting USF2/PPP3R1 axis

Decorin (DCN) is a leucine-rich proteoglycan produced by chorionic villus mesenchymal cells anddecidual cells during human pregnancy. Studies from our laboratory demonstrated that decidua-derived DCN restrains multiple trophoblast functions including proliferation, migration, invasion andendovascular differentiation, mediated by DCN-binding to multiple tyrosine kinase receptors; expressed by the trophoblast. Furthermore, DCN was shown to be selectively over-produced by thedecidua in preeclampsia (PE) subjects and elevated in the second trimester maternal plasma in PE, before the appearance of clinical signs, presenting as a predictive biomarker for PE. Micro (mi)RNAs are single-stranded non-coding RNAs (17–25 nucleotides) that typically downregulate target genes by repressing translation or facilitating degradation of mRNAs. The human; placenta expresses many miRNAs, some of which are exclusively expressed by the trophoblast. Many; of these miRNAs are dysregulated in PE-associated placentas and some appear in the maternal blood as PE biomarkers. However, little is known about their contribution to the pathogenesis of PE, a multi-factorial disease associated with a hypo-invasive placenta. The objective of the present study was to examine whether exposure of extravillous trophoblast (EVT) to DCN affects expression of specific miRNAs, and to test the role of these miRNAs in altering EVT functions. We identified miR-512-3p, as one of the DCN-induced miRNAs, also upregulated in PE placentas. It was shown to be elevated in ectopic DCN-over-expressing or exogenous DCN-treated first trimester human trophoblast cell line HTR-8/SVneo. Use of miRNA-mimics and inhibitors revealed that miR-512-3p compromised trophoblast migration, invasion and VEGF-dependent endovascular differentiation. Finally, Protein Phosphatase 3 Regulatory Subunit B, Alpha (PPP3R1), a known target of miR-512-3p, was paradoxically elevated in miR-512-3p-overexpressing trophoblast and PE-associated placentas. Using Enrichr, a tool that consists of both a validated user-submitted gene list and a search engine for transcription factors, we found that PPP3R1 elevation resulted from the miRNA binding to and targeting Upstream Transcription Factor 2 (USF2) which targeted PPP3R1. These findings reveal a novel aspect of pathogenesis of PE and biomarker potentials of this miRNA in PE.

Potential Use of Anti-Cancer Drugs for Treatment of Preeclampsia by Targeting the miRNA-IGF1R-PI3K-AKT Axis

Aim

Preeclampsia (PE) belongs to hypertensive disorders of pregnancy (HDP), which can cause maternal death worldwide. This study aimed to identify the miRNA-mRNA-associated ceRNA network and to find new treatment schedules for PE.

Methods

4 microarray datasets were downloaded from the Gene Expression Omnibus database. We obtained 1737 differentially expressed mRNAs (865 upregulated and 872 downregulated) and 148 differentially expressed miRNAs (76 upregulated and 72 downregulated) from the placenta tissues of PE, respectively. Functional enrichment analyses of DEmRNAs were performed. The regulatory relationship between DEmiRNAs and DEmRNA was predicted via related databases. An miRNA-mRNA regulatory network was constructed.

Results

hsa-let-7c and IGF1R were identified as potential regulators for PE, and function enrichment analysis showed that the PI3K-Akt signaling pathway was closely related. Therefore, ceRNAs might regulate the PI3K-Akt signaling pathway via the upregulation of IGF1R by binding to hsa-let-7c, affecting invasion of trophoblast, angiogenesis, and proinflammation in PE. Further study demonstrated that anticancer drugs including the PI3K inhibitor, AKT inhibitor, and IGF-1 inhibitor might be a potential solution for PE treatment.

Conclusions

The hsa-let-7c/IGF1R axis might affect the PI3K-Akt signaling pathway which is involved in the pathogenesis of PE, and inhibitors targeting this pathway might be used for PE treatment.

Circ_FURIN promotes trophoblast cell proliferation, migration and invasion in preeclampsia by regulating miR-34a-5p and TFAP2A

Emerging evidence has shown that circular RNAs (circRNAs) play vital roles in the progression of diverse human diseases. However, the functions of circRNAs in preeclampsia (PE) are largely unknown. In this study, we aimed to explore the functions of the circRNA furin, paired basic amino acid cleaving enzyme (circ_FURIN) in PE development. qRT-PCR and western blot analyses were conducted to determine the levels of circ_FURIN, miR-34a-5p and transcription factor AP-2 alpha (TFAP2A). A Cell Counting Kit-8 (CCK-8) assay and a 5'-ethynyl-2'-deoxyuridine (EdU) incorporation assay were utilized to evaluate the cell proliferation ability. Transwell assays were adopted to estimate cell migration and invasion. A dual-luciferase reporter assay and an RNA pulldown assay were utilized to analyze the relationships among circ_FURIN, miR-34a-5p and TFAP2A. It was found that circ_FURIN was downregulated in PE placental tissues and hypoxia-treated placental trophoblast cells. Overexpression of circ_FURIN promoted trophoblast cell proliferation, migration and invasion under hypoxic conditions. Circ_FURIN functioned as the sponge for miR-34a-5p. MiR-34a-5p overexpression abrogated the effects of circ_FURIN on the proliferation, migration and invasion of trophoblast cells under hypoxic conditions. In addition, TFAP2A was demonstrated to be the target gene of miR-34a-5p. TFAP2A silencing ameliorated the promotive effects of miR-34a-5p inhibition on trophoblast cell proliferation, migration and invasion under hypoxic conditions. In conclusion, circ_FURIN enhanced trophoblast cell proliferation, migration and invasion under hypoxic conditions by elevating TFAP2A expression through sponging miR-34a-5p.

Puerarin attenuates preeclampsia-induced trophoblast mobility loss and inflammation by modulating miR-181b-5p/RBAK axis

PROBLEM

Preeclampsia (PE) is a serious pregnancy complication characterized by inflammation and impaired trophoblast motility. Puerarin (Pue) is a functional compound with anti-PE potential. The current study aimed to explore the therapeutic effects of Pue on PE as well as the associated mechanism by focusing on the interaction between Pue and microRNAs (miRs).

METHODS OF STUDY

Human villous trophoblast HTR-8/SVneo cells were treated with TNF-α and Pue, and a change in miR expression profile was determined. The anti-PE effects of Pue were validated in rat models by measuring blood pressure, 24-h proteinuria, and cytokine levels. The mechanism was explored by focusing on miR-181b-5p/RBAK axis.

RESULTS

The induction of PE increased blood pressure and 24-h proteinuria, and induced TNF-α, IL-1β, and IL-6 levels, which was reversed by Pue. In in vitro assays, TNF-α suppressed viability, induced apoptosis and inflammatory response, and inhibited migration in trophoblasts, which was attenuated by Pue. At molecular level, the expression level of miR-181b-5p was both induced in vivo and in vitro with the development of PE symptoms, contributing to the inhibited expression of RBAK. The induced expression of miR-181b-5p under Pue treatment showed that the reinduction of miR-181b-5p counteracted the effects of Pue, indicating the key role of the miR in the protective effects of Pue against PE.

CONCLUSIONS

The current study verified the anti-PE function of Pue: the compound suppressed inflammatory response associated with PE, and improved trophoblast motility. The effects depended on the inhibition of miR-181b-5p that inhibited the expression of RBAK.

MicroRNAs and Heat Shock Proteins in Breast Cancer Biology

Breast cancer has five major immune types; luminal A, luminal B, HER2, Basal-like, and normal-like. Cells produce a family of protein called heat shock proteins (Hsps) in response to exposure to thermal and other proteotoxic stresses play essential roles in cancer metabolism and this large family shows a diverse set of Hsp involvement in different breast cancer immune types. Recently, Hsp members categorized according to their immune type roles. Hsp family consists of several subtypes formed by molecular weight; Hsp70, Hsp90, Hsp100, Hsp40, Hsp60, and small molecule Hsps. Cancer cells employ Hsps as survival factors since most of these proteins prevent apoptosis. Several studies monitored Hsp roles in breast cancer cells and reported Hsp27 involvement in drug resistance, Hsp70 in tumor cell transformation-progression, and interaction with p53. Furthermore, the association of Hsp90 with steroid receptors and signaling proteins in patients with breast cancer directed research to focus on Hsp-based treatments. miRNAs are known to play key roles in all types of cancer that are upregulated or downregulated in cancer which respectively referred to as oncogenes (oncomirs) or tumor suppressors. Expression profiles of miRNAs may be used to classify, diagnose, and predict different cancer types. It is clear that miRNAs play regulatory roles in gene expression and this work reveals miRNA correlation to Hsp depending on specific breast cancer immune types. Deregulation of specific Hsp genes in breast cancer subtypes allows for identification of new targets for drug design and cancer treatment. Here, we performed miRNA network analysis by recruiting Hsp genes detected in breast cancer subtypes and reviewed some of the miRNAs related to aforementioned Hsp genes.

High-Throughput Sequencing of Circulating MicroRNAs in Plasma and Serum during Pregnancy Progression

Although circulating microRNAs (miRNAs) in maternal blood may play an important role in regulation of pregnancy progression and serve as non-invasive biomarkers for different gestation complications, little is known about their profile in blood during normally developing pregnancy. In this study we evaluated the miRNA profiles in paired plasma and serum samples from pregnant women without health or gestational abnormalities at three time points using high-throughput sequencing technology. Sequencing revealed that the percentage of miRNA reads in plasma and serum decreased by a third compared to first and second trimesters. We found two miRNAs in plasma (hsa-miR-7853-5p and hsa-miR-200c-3p) and 10 miRNAs in serum (hsa-miR-203a-5p, hsa-miR-495-3p, hsa-miR-4435, hsa-miR-340-5p, hsa-miR-4417, hsa-miR-1266-5p, hsa-miR-4494, hsa-miR-134-3p, hsa-miR-5008-5p, and hsa-miR-6756-5p), that exhibit level changes during pregnancy (p-value adjusted < 0.05). In addition, we observed differences for 36 miRNAs between plasma and serum (p-value adjusted < 0.05), which should be taken into consideration when comparing the results between studies performed using different biosample types. The results were verified by analysis of three miRNAs using qRT-PCR (p < 0.05). The present study confirms that the circulating miRNA profile in blood changes during gestation. Our results set the basis for further investigation of molecular mechanisms, involved in regulation of pregnancy, and the search for biomarkers of gestation abnormalities.

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

Preeclampsia (PE) is a leading cause of maternal and neonatal morbidity and mortality worldwide. Defects in trophoblast invasion, differentiation of extravillous trophoblasts and spiral artery remodeling are key factors in PE development. Currently there are no predictive biomarkers clinically available for PE. Recent technological advancements empowered transcriptome exploration and led to the discovery of numerous non-coding RNA species of which microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) are the most investigated. They are implicated in the regulation of numerous cellular functions, and as such are being extensively explored as potential biomarkers for various diseases. Altered expression of numerous lncRNAs and miRNAs in placenta has been related to pathophysiological processes that occur in preeclampsia. In the following text we offer summary of the latest knowledge of the molecular mechanism by which lnRNAs and miRNAs (focusing on the chromosome 19 miRNA cluster (C19MC)) contribute to pathophysiology of PE development and their potential utility as biomarkers of PE, with special focus on sample selection and techniques for the quantification of lncRNAs and miRNAs in maternal circulation.

HSPA8 Is Identified as a Novel Regulator of Hypertensive Disorders in Pregnancy by Modulating the β-Arrestin1/A1AR Axis

Heat shock protein alpha 8 (HSPA8) was found to be downregulated in the placentas of patients with hypertensive disorders in pregnancy (HDP). We aim to explore the underlying role and mechanism of HSPA8 in HDP progression. Herein, HSPA8 mRNA expression in placentas and peripheral blood of patients with HDP and normal pregnant controls was measured with RT-qPCR. We found that HSPA8 expression was downregulated in placentas and peripheral blood of patients with HDP. HTR8/SVneo human trophoblast cells were transfected with pcDNA-HSPA8 or si-HSPA8. HSPA8 overexpression promoted cell proliferation, migration, and MMP-2 and MMP-9 protein levels, and inhibited apoptosis, while HSPA8 silencing showed the opposite results. Co-immunoprecipitation assay validated the binding between HSPA8 and β-arrestin1, as well as β-arrestin1 and A1AR proteins. HSPA8 bound with β-arrestin1 protein and promoted β-arrestin1 expression. β-arrestin1 bound with A1AR protein and inhibited A1AR expression. Then, HTR8/SVneo cells were transfected with pcDNA-HSPA8 alone or together with si-β-arrestin1, as well as transfected with pcDNA-β-arrestin1 alone or together with pcDNA-A1AR. β-arrestin1 silencing reversed the effects of HSPA8 overexpression on HTR8/SVneo cell functions. β-arrestin1 overexpression promoted cell proliferation migration, and MMP-2 and MMP-9 protein levels, and inhibited apoptosis, while these effects were reversed by A1AR overexpression. Lentivirus HSPA8 overexpression vector (Lv-HSPA8) was injected into a preeclampsia (PE) rat model, which attenuated blood pressure and fetal detrimental changes in PE rats. In conclusion, HSPA8 promoted proliferation and migration and inhibited apoptosis in trophoblast cells, and attenuated the symptoms of PE rats by modulating the β-arrestin1/A1AR axis. Our study provided a novel theoretical evidence and potential strategy for HDP treatment.

High-throughput miRNA sequencing of the human placenta: expression throughout gestation

Aim: To understand miRNA changes across gestation in healthy human placentae. This is essential before miRNAs can be used as biomarkers or prognostic indicators during pregnancy. Materials & methods: Using next-generation sequencing, we characterize the normative human placenta miRNome in first (n = 113) and third trimester (n = 47). Results & conclusion: There are 801 miRNAs expressed in both first and third trimester, including 182 with similar expression across gestation (p ≥ 0.05, fold change ≤2) and 180 significantly different (false discovery rate <0.05, fold change >2). Of placenta-specific miRNA clusters, chromosome 14 miRNA cluster decreases across gestation and chromosome 19 miRNA cluster is overall highly expressed. Chromosome 13 clusters are upregulated in first trimester. This work provides a rich atlas of healthy pregnancies to direct functional studies investigating the epigenetic differences in first and third trimester placentae.

MicroRNA-362-5p promotes the proliferation and inhibits apoptosis of trophoblast cells via targeting glutathione-disulfide reductase

Gestational diabetes mellitus (GDM), a common complication of pregnancy, harms the health of pregnant women and fetuses. MicroRNAs (miRNAs) dysregulation in placenta is involved in GDM. Herein, we explored the roles of miR-362-5p in GDM. After high glucose (HG) treated HTR-8/SVneo cells, CCK-8 and flow cytometry were conducted to assess the capability of the proliferation and apoptosis, respectively. The data demonstrated that HG inhibited proliferation and induced apoptosis of HTR-8/SVneo cells. MiR-362-5p level was reduced in HG-treated cells and placenta tissues of GDM patients, measured by qPCR. Overexpressed miR-362-5p accelerated the proliferation and restrained apoptosis of HG-treated cells. Furthermore, glutathione-disulfide reductase (GSR) was verified as a target of miR-362-5p, through TargetScan database and dual-luciferase reporter assay. GSR was upregulated in GDM placenta tissues and was negatively regulated by miR-362-5p. Enforced GSR level abolished the effects of miR-362-5p overexpression on the proliferation and apoptosis of HTR-8/SVneo cells. Furthermore, miR-362-5p increased p-PI3K, p-AKT and bcl-2, while reduced bax and cleaved caspase3, which were abolished by GSR. In conclusion, miR-362-5p promoted cell proliferation and inhibited apoptosis via targeting GSR and activating PI3K/AKT pathway. The findings mentioned above suggested that miR-362-5p might be a therapy target of GDM.

Analysis of Circulating microRNA Signatures and Preeclampsia Development

microRNAs are important regulators of cell processes and have been proposed as potential preeclampsia biomarkers. We evaluated serum microRNA expression profiling to identify microRNAs involved in preeclampsia development. Serum microRNA expression profiling was evaluated at 12, 16, and 20 weeks of gestation (WG), and at the time of preeclampsia diagnosis. Two groups were evaluated using TaqMan low-density array plates: a control group with 18 normotensive pregnant women and a case group with 16 patients who developed preeclampsia during the follow-up period. Fifty-three circulating microRNAs were differentially expressed between groups (p < 0.05). Compared with controls, hsa-miR-628-3p showed the highest relative quantity values (at 12 WG = 7.7 and at 20 WG = 3.45) and the hsa-miRs -151a-3p and -573 remained differentially expressed from 16 to 20 WG (p < 0.05). Signaling pathways including cancer-related, axon guidance, Neurotrophin, GnRH, VEGF, and B/T cell receptor, were most commonly altered. Further target gene prediction revealed that nuclear factor of activated T-cells 5 gene was included among the transcriptional targets of preeclampsia-modulated microRNAs. Specific microRNAs including hsa-miRs -628-3p, -151a-3p, and -573 were differentially expressed in serum of pregnant women before they developed preeclampsia compared with controls and their participation in the preeclampsia development should be considered.

Insight into the Key Points of Preeclampsia Pathophysiology: Uterine Artery Remodeling and the Role of MicroRNAs

Preeclampsia affects about 3-8% of all pregnancies. It represents a complex and multifaceted syndrome with at least several potential pathways leading to the development of disease. The main dogma in preeclampsia is the two-stage model of disease. Stage 1 (placental stage) takes place in early pregnancy and is thought to be impaired placentation due to inadequate trophoblastic invasion of the maternal spiral arteries that leads to reduced placental perfusion and release of numerous biological factors causing endothelial damage and development of acute maternal syndrome with systemic multiorgan failure (stage 2-the onset of maternal clinical symptoms, maternal stage). Recently, in the light of the vast body of evidence, two-stage model of preeclampsia has been updated with a few novel pathways leading to clinical manifestation in the second part of pregnancy. This paper reviews current state of knowledge about pathophysiology of preeclampsia and places particular focus on the recent advances in understanding of uterine artery remodeling alterations, as well as the role of microRNAs in preeclampsia.

MicroRNA Signature of Epithelial-Mesenchymal Transition in Group B Streptococcal Infection of the Placental Chorioamniotic Membranes

BACKGROUND

Infection-induced preterm birth is a major cause of neonatal mortality and morbidity and leads to preterm premature rupture of placental chorioamniotic membranes. The loss of amniotic epithelial cells and tensile strength preceding membrane rupture is poorly understood. We hypothesized that intrauterine bacterial infection induces changes in microRNA (miRNA) expression, leading to amniotic epithelial cell loss and membrane weakening.

METHODS

Ten pregnant pigtail macaques received choriodecidual inoculation of either group B Streptococcus (GBS) or saline (n = 5/group). Placental chorioamniotic membranes were studied using RNA microarray and immunohistochemistry. Chorioamniotic membranes from women with preterm premature rupture of membranes (pPROM) and normal term pregnancies were studied using transmission electron microscopy.

RESULTS

In our model, an experimental GBS infection was associated with changes in the miRNA profile in the chorioamniotic membranes consistent with epithelial to mesenchymal transition (EMT) with loss of epithelial (E-cadherin) and gain of mesenchymal (vimentin) markers. Similarly, loss of desmosomes (intercellular junctions) was seen in placental tissues from women with pPROM.

CONCLUSIONS

We describe EMT as a novel mechanism for infection-associated chorioamniotic membrane weakening, which may be a common pathway for many etiologies of pPROM. Therapy based on anti-miRNA targeting of EMT may prevent pPROM due to perinatal infection.

Peroxisome Proliferator-Activated Receptors (PPAR), fatty acids and microRNAs: Implications in women delivering low birth weight babies

Low birth weight (LBW) babies are associated with neonatal morbidity and mortality and are at increased risk for noncommunicable diseases (NCDs) in later life. However, the molecular determinants of LBW are not well understood. Placental insufficiency/dysfunction is the most frequent etiology for fetal growth restriction resulting in LBW and placental epigenetic processes are suggested to be important regulators of pregnancy outcome. Early life exposures like altered maternal nutrition may have long-lasting effects on the health of the offspring via epigenetic mechanisms like DNA methylation and microRNA (miRNA) regulation. miRNAs have been recognized as major regulators of gene expression and are known to play an important role in placental development. Angiogenesis in the placenta is known to be regulated by transcription factor peroxisome proliferator-activated receptor (PPAR) which is activated by ligands such as long-chain-polyunsaturated fatty acids (LCPUFA). In vitro studies in different cell types indicate that fatty acids can influence epigenetic mechanisms like miRNA regulation. We hypothesize that maternal fatty acid status may influence the miRNA regulation of PPAR genes in the placenta in women delivering LBW babies. This review provides an overview of miRNAs and their regulation of PPAR gene in the placenta of women delivering LBW babies.Abbreviations: AA - Arachidonic Acid; Ago2 - Argonaute2; ALA - Alpha-Linolenic Acid; ANGPTL4 - Angiopoietin-Like Protein 4; C14MC - Chromosome 14 miRNA Cluster; C19MC - Chromosome 19 miRNA Cluster; CLA - Conjugated Linoleic Acid; CSE - Cystathionine γ-Lyase; DHA - Docosahexaenoic Acid; EFA - Essential Fatty Acids; E2F3 - E2F transcription factor 3; EPA - Eicosapentaenoic Acid; FGFR1 - Fibroblast Growth Factor Receptor 1; GDM - Gestational Diabetes Mellitus; hADMSCs - Human Adipose Tissue-Derived Mesenchymal Stem Cells; hBMSCs - Human Bone Marrow Mesenchymal Stem Cells; HBV - Hepatitis B Virus; HCC - Hepatocellular Carcinoma; HCPT - Hydroxycamptothecin; HFD - High-Fat Diet; Hmads - Human Multipotent Adipose-Derived Stem; HSCS - Human Hepatic Stellate Cells; IUGR - Intrauterine Growth Restriction; LA - Linoleic Acid; LBW - Low Birth Weight; LCPUFA - Long-Chain Polyunsaturated Fatty Acids; MEK1 - Mitogen-Activated Protein Kinase 1; MiRNA - MicroRNA; mTOR - Mammalian Target of Rapamycin; NCDs - NonCommunicable Diseases; OA - Oleic Acid; PASMC - Pulmonary Artery Smooth Muscle Cell; PLAG1 - Pleiomorphic Adenoma Gene 1; PPAR - Peroxisome Proliferator-Activated Receptor; PPARα - PPAR alpha; PPARγ - PPAR gamma; PPARδ - PPAR delta; pre-miRNA - precursor miRNA; RISC - RNA-Induced Silencing Complex; ROS - Reactive Oxygen Species; SAT - Subcutaneous Adipose Tissue; WHO - World Health Organization.

MicroRNA-210 Mediates Hypoxia-Induced Repression of Spontaneous Transient Outward Currents in Sheep Uterine Arteries During Gestation

[Figure: see text].

Rhynchophylline improves trophocyte mobility potential by upregulating ZEB1 level via the inhibition of miR-141-3p level

Preeclampsia (PE) is characterized by the impaired invasive ability of trophocytes, which can be modulated by microRNAs (miRs). In the current study, the effects of rhynchophylline (Rhy) on the viability and invasive ability of trophocytes were explored by focusing on miR-141-3p/ZEB1 axis. The level of miR-141-3p was modulated in human trophocytes and the changes in cell viability, apoptosis, invasive ability, and ZEB1 level were detected. Then the trophocytes with miR-141-3p overexpression were treated with Rhy and the effects on trophocyte phenotypes were assessed. The induced miR-141-3p level suppressed cell viability, induced apoptosis, and inhibited invasion and ZEB1 level in trophocytes. The treatment of Rhy restored the viability and invasive ability of trophocytes under the overexpression of miR-141-3p, indicating the protective effects of Rhy on trophocytes. The findings in the current study highlighted the protective effects of Rhy on trophocytes during PE progression, which was associated with the inhibition of miR-141-3p.

Downregulation of miR-126-3p expression contributes to increased inflammatory response in placental trophoblasts in preeclampsia

MiR-126-3p is a prototype of an endothelial miRNA and has protective effects on endothelial cells. However, little is known about the effects of miR-126-3p on placental trophoblasts. In the present study, we tested the hypothesis that aberrant miR-126-3p expression is present in preeclamptic placenta which contributes to increased inflammatory response in trophoblasts. Placentas were obtained immediately after delivery from normotensive and preeclamptic pregnancies. Villous tissue was either fixed with formalin or used for trophoblast isolation. Trophoblast miR-126-3p expression was assessed by in situ hybridization of formalin-fixed tissue sections and by RT-PCR in cultured syncytiotrophoblasts. Culture medium was collected for measurement of IL-6, TNFα, and 8-Isoprostane production by ELISA and total cellular protein was collected for evaluation of HIF1α expression by Western blot. Effects of overexpression of miR-126-3p in trophoblasts on cytokine production were tested by transfection of pre-mir-126, a precursor of miR-126, into primary isolated trophoblasts. We found that downregulation of miR-126-3p expression was associated with increased IL-6 and TNFα production in trophoblasts from preeclamptic placentas vs. normal placentas. Moreover, transient overexpression of miR-126-3p significantly reduced IL-6 and TNFα production in trophoblasts from both normal and preeclamptic placentas. We further found that increase in miR-126-3p expression not only suppressed hypoxia-induced increases in IL-6 and TNFα production, but also attenuated hypoxia-induced increases in HIF1α expression and 8-Isoprostane production in trophoblasts cultured under hypoxic condition. These results provide plausible evidence that downregulation of miR-126-3p expression reduces anti-inflammatory and anti-oxidative stress activities in placental trophoblasts in preeclampsia.

Information on dysregulation of microRNA in placenta linked to preeclampsia

MicroRNAs are single-stranded, non-coding RNA molecules, regulate gene expression at the post-transcriptional level. They are expressed in the human body and have a significant impact on the different processes of pathological illness. A developing placenta undergoes a series of stages after successful fertilization, such as cell division, migration, adhesion, apoptosis, and angiogenesis. MicroRNAs dysregulation in placenta has been linked to pregnancy-related complications such as preeclampsia. Therefore, it is of interest to document known information (list of microRNA) on this issue in the development of biological tools for diagnosis, treatment and prevention of the disease.

MiRNAs in Gestational Diabetes Mellitus: Potential Mechanisms and Clinical Applications

Gestational diabetes mellitus (GDM) is a common pregnancy complication which is normally diagnosed in the second trimester of gestation. With an increasing incidence, GDM poses a significant threat to maternal and offspring health. Therefore, we need a deeper understanding of GDM pathophysiology and novel investigation on the diagnosis and treatment for GDM. MicroRNAs (miRNAs), a class of endogenic small noncoding RNAs with a length of approximately 19-24 nucleotides, have been reported to exert their function in gene expression by binding to proteins or being enclosed in membranous vesicles, such as exosomes. Studies have investigated the roles of miRNAs in the pathophysiological mechanism of GDM and their potential as noninvasive biological candidates for the management of GDM, including diagnosis and treatment. This review is aimed at summarizing the pathophysiological significance of miRNAs in GDM development and their potential function in GDM clinical diagnosis and therapeutic approach. In this review, we summarized an integrated expressional profile and the pathophysiological significance of placental exosomes and associated miRNAs, as well as other plasma miRNAs such as exo-AT. Furthermore, we also discussed the practical application of exosomes in GDM postpartum outcomes and the potential function of several miRNAs as therapeutic target in the GDM pathological pathway, thus providing a novel clinical insight of these biological signatures into GDM therapeutic approach.

An association study between MiR-146a and INSR gene polymorphisms and hypertensive disorders of pregnancy in Northeastern Han Chinese population

INTRODUCTION

Hypertensive disorders of pregnancy(HDP) is a complex and challenging group of pregnancy complications that is one of the leading causes of maternal and fetal death worldwide. Recent studies have shown that the single nucleotide polymorphism(SNP) may play a role in the pathogenesis of HDP. This study aimed to investigate the association of MiR-146a rs2910164 and insulin receptor(INSR) rs2059806 SNPs with HDP and their associated complications in the Han population of Northeast China.

METHODS

A total of 240 HDP patients and 380 healthy controls were selected for genotype determination. For the most special and high incidence of HDP, we also studied the SNPs in association with pre-eclampsia(PE) patients. In addition, HDP complicated with gestational diabetes mellitus(GDM) patients was further analyzed to identify the association between SNPs and HDP-related complications. Multivariate logical regression analysis combined with 10, 000 permutation test corrections was used to analyze the association of MiR-146a and INSR SNPs with HDP.

RESULTS

After adjusting for relevant factors, MiR-146a rs2910164 or INSR rs2059806 SNPs were not significantly different between HDP or PE patients and healthy controls(P>0.05). Meanwhile, MiR146a rs2910164 and INSR rs2059806 SNPs were not significantly different between HDP complicated with GDM and control group.

DISCUSSION

Our data indicates that MiR-146a rs2910164 and INSR rs2059806 SNPs may not be significantly related with HDP in the Han population of Northeast China living in Heilongjiang Province.

Circ_0001438 participates in the pathogenesis of preeclampsia via the circ_0001438/miR-942/NLRP3 regulatory network

INTRODUCTION

Preeclampsia (PE) is a common pregnancy disorder with multisystem complications. The growing data suggest that circular RNAs (circRNAs) involve in the development of PE. This study proposed to investigate the function and potential mechanisms of circ_0001438 in PE.

METHODS

The expression of circ_0001438, miR-942 and NOD-like receptor pyrin domain-containing protein 3 (NLRP3) was measured by quantitative real-time polymerase chain reaction (qRT-PCR). The expression at the protein level of NLRP3, interleukin 1 beta (IL-1β), interleukin 10 (IL-10), B-cell lymphoma 2 (Bcl-2), Cleaved-caspase-3 (Cleaved-casp-3), N-cadherin and E-cadherin was detected by Western blot. Cell proliferation was assessed by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay and colony formation assay. Cell apoptosis was determined by flow cytometry assay. Cell migration and invasion were monitored by transwell assay. The target genes were obtained and verified by the online bioinformatics tool and dual-luciferase reporter assay.

RESULTS

The expression of circ_0001438 and NLRP3 was enhanced in PE placenta tissues. Circ_0001438 knockdown promoted cell proliferation, migration and invasion but inhibited apoptosis and inflammatory responses in HTR-8/Svneo cells, and these effects were reversed by the inhibition of miR-942, a target of circ_0001438. Moreover, NLRP3 was bounded by miR-942. The enrichment of miR-942 accelerated cell proliferation, migration and invasion but depleted apoptosis and inflammatory responses, while these impacts were partly abolished by NLRP3 overexpression.

DISCUSSION

Circ_0001438 sponged miR-942 to regulate the expression of NLRP3, and circ_0001438 aggravated the dysfunctions of human villous trophoblasts by mediating the miR-942/NLRP3 axis at least in part.

Extracellular Vesicles in Essential Hypertension: Hidden Messengers

PURPOSE OF REVIEW

Hypertension affects about half of all Americans, yet in the vast majority of cases, the factors causing the hypertension cannot be clearly delineated. Developing a more precise understanding of the molecular pathogenesis of HTN and its various phenotypes is therefore a pressing priority. Circulating and urinary extracellular vesicles (EVs) are potential novel candidates as biomarkers and bioactivators in HTN. EVs are a heterogeneous population of small membrane fragments shed from various cell types into various body fluids. As EVs carry protein, RNA, and lipids, they also play a role as effectors and novel cell-to-cell communicators. In this review, we discuss the diagnostic, functional, and regenerative role of EVs in essential HTN and focus on EV protein and RNA cargo as the most extensively studied EV cargo.

RECENT FINDINGS

The field of EVs in HTN is still a young one and earlier studies have not used the novel EV detection tools currently available. More rigor and transparency in EV research are needed. Current data suggest that EVs represent potential novel biomarkers in HTN. EVs correlate with HTN severity and possibly end-organ damage. However, it has yet to be discerned which specific subtype(s) of EV reflects best HTN pathophysiology. Evolving studies are also showing that EVs might be novel regulators in vascular and renal tubular function and also be therapeutic. RNA in EVs has been studied in the context of hypertension, largely in the form of studies of miRNA, which are reviewed herein. Beyond miRNAs, mRNA in urinary EVs changed in response to sodium loading in humans. EVs represent promising novel biomarkers and bioactivators in essential HTN. Novel tools are being developed to apply more rigor in EV research including more in vivo models and translation to humans.

MiR-135a-5p promotes the migration and invasion of trophoblast cells in preeclampsia by targeting β-TrCP

BACKGROUND

MiR-135a-5p is an important regulator of cell migration and invasion in several diseases. However, the biological functions and mechanisms of miR-135a-5p in women with preeclampsia (PE) remain unclear.

METHODS

The levels of miR-135a-5p and beta-transducin repeat containing E3 ubiquitin protein ligase (β-TrCP) expression in samples of placenta tissue from PE patients and healthy control subjects were determined by quantitative real-time PCR. The effects of miR-135a-5p and β-TrCP on cell migration, invasion, and epithelial-mesenchymal transition (EMT) in two trophoblast cell lines (HTR-8/SVneo and TEV-1) were examined using wound healing, Transwell, and western blot assays, respectively. A luciferase reporter assay was performed to confirm the association between miR-135a-5p and β-TrCP, and an in vivo mouse model was established and used to analyze the effect of β-TrCP on PE clinical phenotypes.

RESULTS

We found that miR-135a-5p expression was significantly decreased and negatively correlated with β-TrCP expression in the placental tissues of pregnant women with PE. Cellular function experiments showed that overexpression of miR-135a5p promoted the migration and invasion of trophoblast cells in vitro. Furthermore, β-TrCP was confirmed as a target gene of miR-135a-5p in trophoblast cells. Notably, overexpression of β-TrCP significantly reversed the effect of miR-135a-5p on migration and invasion of trophoblast cells. At the molecular level, decreases in E-cadherin levels and increases in N-cadherin, Vimentin, and β-catenin levels that were induced by miR-135a-5p overexpression were attenuated by β-TrCP overexpression.

CONCLUSIONS

Our findings demonstrate that miR-135a-5p promotes the migration and invasion of trophoblast cells by targeting β-TrCP.

Preeclampsia serum increases CAV1 expression and cell permeability of human renal glomerular endothelial cells via down-regulating miR-199a-5p, miR-199b-5p, miR-204

INTRODUCTION

To gain insight into mechanisms of preeclampsia (PE)-dependent proteinuria, this study focused on whether preeclampsia serum (PES) could induce hyperpermeability in human renal glomerular endothelial cells (HRGECs) via the miRNAs-Caveolin-1 (CAV-1)-dependent pathway.

METHODS

Bioinformatics approach was used to identify miRNAs targeting CAV1. Normal pregnancy serum (NPS) and severe PES were used to treat HRGECs monolayer to demonstrate if PES could induce the expression of identified miRNAs. A luciferase reporter assay was used to determine whether CAV1 was a direct target of miR-199a-5p, miR-199b-5p, and miR-204. The relationship between the expression of miR-199a-5p, miR-199b-5p, miR-204, and CAV1 in HRGECs was determined using quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blot. The gain-of-function and loss-of-function experiments were performed on HRGECs to investigate the effects of miR-199a-5p, miR-199b-5p, miR-204 on HRGECs permeability.

RESULTS

We identified that CAV1 3'UTR has putative binding sites for miR-199a-5p, miR-199b-5p, and miR-204, whereas miR-199a-5p does not appear to be a direct regulator of CAV1. We detected that PE serum downregulated the expression of miR-199a-5p, miR-199b-5p and miR-204, increased expression of CAV1 and increased cell monolayer permeability in HRGECs. The level of CAV1 and permeability decreased when miR-199b-5p or miR-204, but not miR-199a-5p, were overexpressed.

DISCUSSION

miR-199b-5p and miR-204 may play a role in PES-induced increasing permeability of HRGECs by regulating CAV1 expression.

From animal models to patients: the role of placental microRNAs, miR-210, miR-126, and miR-148a/152 in preeclampsia

Placental microRNAs (miRNAs) regulate the placental transcriptome and play a pathological role in preeclampsia (PE), a hypertensive disorder of pregnancy. Three PE rodent model studies explored the role of placental miRNAs, miR-210, miR-126, and miR-148/152 respectively, by examining expression of the miRNAs, their inducers, and potential gene targets. This review evaluates the role of miR-210, miR-126, and miR-148/152 in PE by comparing findings from the three rodent model studies with in vitro studies, other animal models, and preeclamptic patients to provide comprehensive insight into genetic components and pathological processes in the placenta contributing to PE. The majority of studies demonstrate miR-210 is upregulated in PE in part driven by HIF-1α and NF-κBp50, stimulated by hypoxia and/or immune-mediated processes. Elevated miR-210 may contribute to PE via inhibiting anti-inflammatory Th2-cytokines. Studies report an up- and downregulation of miR-126, arguably reflecting differences in expression between cell types and its multifunctional capacity. MiR-126 may play a pro-angiogenic role by mediating the PI3K-Akt pathway. Most studies report miR-148/152 family members are upregulated in PE. Evidence suggests they may inhibit DNA methylation of genes involved in metabolic and inflammatory pathways. Given the genetic heterogeneity of PE, it is unlikely that a single placental miRNA is a suitable therapeutic target for all patients. Investigating miRNAs in PE subtypes in patients and animal models may represent a more appropriate approach going forward. Developing methods for targeting placental miRNAs and specific placental cell types remains crucial for research seeking to target placental miRNAs as a novel treatment for PE.

miR-183-5p suppressed the invasion and migration of HTR-8/SVneo trophoblast cells partly via targeting MMP-9 in preeclampsia

Preeclampsia (PE), a common obstetrical disorder, is characterized by impaired migration and invasion abilities of trophoblastic cells. MicroRNA-183-5p (miR-183) was reported to regulate cell migration and invasion in various types of human cancers; however, its role in the pathogenesis of PE remains elusive. Herein, we investigated the role of miR-183 in HTR-8/SVneo trophoblast cells invasion and migration and explored the underlying mechanism. Our results showed that miR-183 was significantly up-regulated in placental tissues from pregnant women compared with that in normal pregnant women. Overexpression of miR-183 inhibited proliferation, migration and invasion, as well as induced apoptosis in HTR-8/SVneo cells. Otherwise, down-regulation of miR-183 achieved the opposite effects. Bioinformatics prediction and luciferase reporter assay confirmed that matrix metalloproteinase-9 (MMP-9) is a target of miR-183. In addition, MMP-9 expression was significantly down-regulated, and inversely correlated with the miR-183 level in placental tissues from pregnant women with severe PE. Down-regulation of MMP-9 suppressed the trophoblast cell invasion and migration, whereas overexpression of MMP-9 promoted cell invasion and migration in HTR-8/SVneo cells. More importantly, up-regulation of MMP-9 reversed the inhibitory effects of miR-183 on cell invasion and migration in trophoblast cells. Collectively, our findings suggested that miR-183 may play critical roles in the pathogenesis of PE and serve as a potential biomarker for severe PE.

Association between maternal HIV infection and birthweight in a tertiary hospital in southern Ethiopia: retrospective cohort study

BACKGROUND

Human Immunodeficiency Virus (HIV) infection and low birth weight (LBW) continue to be significant public health concerns in many low-income countries including Ethiopia. Yet the effect of maternal HIV infection on birth weight has not been thoroughly explored and the existing studies reported opposing findings. We examined the association between maternal HIV infection and LBW in a tertiary hospital in Southern Ethiopia.

METHODS

A retrospective cohort study was conducted based on the medical records of 277 HIV-negative and 252 HIV-positive mothers who gave singleton live birth between September 2014 to August 2017 in Hawassa University Comprehensive Specialized Hospital, Southern Ethiopia. The recodes were identified using systematic sampling approach and relevant information were extracted by using pretested extraction form. Multivariable binary logit model was fitted to examine the relationship between the exposure and outcome while adjusting for potential confounders. Adjusted odds ratio (AOR) and 95% confidence intervals (CI) is used for summarizing the findings of the analysis.

RESULTS

The mean (± standard deviation) birth weight of infants born to HIV-negative women (3.1 ± 0.7 kg) was significantly higher than those born to HIV-positive counterparts (3.0 ± 0.6 kg) (p = 0.020). The prevalence of LBW was also significantly higher in the HIV-exposed group (22.2%) than the non-exposed group (13.7%) (p = 0.011). In the logit model adjusted for multiple covariates, HIV-positive women had four times increased odds than HIV-negative women to give birth to LBW infant(AOR = 4.03, 95% CI: 2.01-8.06). Other significant predictors of LBW were rural place of residence (AOR = 2.04, 95% CI: 1.16-3.60), prenatal anemia (AOR = 3.17, 95% CI: 1.71-5.90), chronic hypertension (AOR = 3.68, 95% CI: 1.10-12.46) and preeclampsia (AOR = 6.80, 95% CI: 3.00-15.38).

CONCLUSION

Maternal HIV infection is associated with increased odds of LBW. HIV prevention activities are also likely to contribute for the reduction of LBW.

Elevated microRNA-125b inhibits cytotrophoblast invasion and impairs endothelial cell function in preeclampsia

Preeclampsia (PE) is a life-threatening disorder of human pregnancy affecting 5-8% of all pregnancies. Currently, PE remains an elusive complicated and heterogenous medical condition with no early marker or symptoms is recognized for this serious pregnancy complications. Here, we profiled the plasma miRNA expression patterns associated with preeclampsia and found 16 miRNAs were deregulated (p < 0.01) in patients who later developed PE. Circulating hsa-miR-125b was aberrantly upregulated in early pregnancy and significantly reduced after delivery in preeclampsia. We then investigated the underlying molecular mechanisms between miR-125b and PE in vitro. We found that upregulated miR-125b can target KCNA1 to inhibit trophoblast invasion in human trophoblast cells. Moreover, overexpression of miR-125b in HUVECs impaired endothelial cell function through GPC1. The findings indicated that upregulated miR-125b leads to impaired placentation, and an increased risk of preeclampsia, Our studies provide novel insights into the underlying mechanisms on the association of miR-125b in early pregnancy and risk of PE, miR-125b might be a more specific predictive marker and a safe therapeutic target for treating patients with PE.

HMGA2 is regulated by LIN28 and BRCA1 in human placental cells

The chromatin associated transcription factor HMGA2 is a downstream target of let-7 miRNAs and binds to chromatin to regulate gene expression. Inhibition of let-7 miRNAs by RNA-binding proteins LIN28A and LIN28B is necessary during early embryogenesis to ensure stable expression of HMGA2. In addition to LIN28, HMGA2 is regulated by a BRCA1/ZNF350/CtIP repressor complex. In normal tissues, the BRCA1/ZNF350/CtIP complex binds to the HMGA2 promoter to prevent transcription. However, in many cancers the oncomiR miR-182 targets BRCA1, preventing BRCA1 translation and allowing for increased HMGA2. Little is known about the regulation of HMGA2 during early placental development; therefore, we hypothesized that both LIN28 and BRCA1 can regulate HMGA2 in placental cells. Using siRNA and CRISPR gene editing techniques, we found that knockdowns of both LIN28A and LIN28B increase HMGA2 levels in ACH-3P cells. These cells also demonstrated deficiencies in cell differentiation, seemingly differentiating solely towards the syncytiotrophoblast sublineage, secreting higher amounts of hCG, and displaying upregulated ERVW-1. Additionally, we found that a knockout of both LIN28A and LIN28B caused a significant increase of miR-182 and a decrease in BRCA1 allowing HMGA2 mRNA levels to increase and protein levels to remain the same. Using chromatin immunoprecipitation, we saw binding of the BRCA1 repressor complex to HMGA2. We also saw a decrease in binding to HMGA2's promoter in the LIN28A/B knockout cells. These findings suggest a novel role for BRCA1 during early human placental development.