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

LncRNA MRAK052509 competitively adsorbs miR-204-3p to regulate silica dust-induced EMT process

Silicosis is a systemic disease caused by long-term inhalation of free SiO2 and retention in the lungs. At present, it is still the most important occupational health hazard disease in the world. Existing studies have shown that non-coding RNA can also participate in complex fibrosis regulatory networks. However, its role in regulating silicotic fibrosis is still unclear. In this study, we constructed a NR8383/RLE-6TN co-culture system to simulate the pathogenesis of silicosis in vitro. Design of miR-204-3p mimics and inhibitors to overexpress or downregulate miR-204-3p in RLE-6TN cells. Design of short hairpin RNA (sh-RNA) to downregulate MRAK052509 in RLE-6TN cells. The regulatory mechanism of miR-204-3p and LncRNA MRAK052509 on EMT process was studied by Quantitative real-time PCR, Western blotting, Immunofluorescence and Cell scratch test. The results revealed that miR-204-3p affects the occurrence of silica dust-induced cellular EMT process mainly through regulating TGF-βRΙ, a key molecule of TGF-β signaling pathway. In contrast, Lnc MRAK052509 promotes the EMT process in epithelial cells by competitively adsorbing miR-204-3p and reducing its inhibitory effect on the target gene TGF-βRΙ, which may influence the development of silicosis fibrosis. This study perfects the targeted regulation relationship between LncRNA MRAK052509, miR-204-3p and TGF-βRΙ, and may provide a new strategy for the study of the pathogenesis and treatment of silicosis.

Value of Non-Coding RNA Expression in Biofluids to Identify Patients at Low Risk of Pathologies Associated with Pregnancy

Pregnancy-related complications (PRC) impact maternal and fetal morbidity and mortality and place a huge burden on healthcare systems. Thus, effective diagnostic screening strategies are crucial. Currently, national and international guidelines define patients at low risk of PRC exclusively based on their history, thus excluding the possibility of identifying patients with de novo risk (patients without a history of disease), which represents most women. In this setting, previous studies have underlined the potential contribution of non-coding RNAs (ncRNAs) to detect patients at risk of PRC. However, placenta biopsies or cord blood samples are required, which are not simple procedures. Our review explores the potential of ncRNAs in biofluids (fluids that are excreted, secreted, or developed because of a physiological or pathological process) as biomarkers for identifying patients with low-risk pregnancies. Beyond the regulatory roles of ncRNAs in placental development and vascular remodeling, we investigated their specific expressions in biofluids to determine favorable pregnancy outcomes as well as the most frequent pathologies of pregnant women. We report distinct ncRNA panels associated with PRC based on omics technologies and subsequently define patients at low risk. We present a comprehensive analysis of ncRNA expression in biofluids, including those using next-generation sequencing, shedding light on their predictive value in clinical practice. In conclusion, this paper underscores the emerging significance of ncRNAs in biofluids as promising biomarkers for risk stratification in PRC. The investigation of ncRNA expression patterns and their potential clinical applications is of diagnostic, prognostic, and theragnostic value and paves the way for innovative approaches to improve prenatal care and maternal and fetal outcomes.

microRNA-203 Targets Insulin-Like Growth Factor Receptor 1 to Inhibit Trophoblast Vascular Remodeling to Augment Preeclampsia

OBJECTIVE

 Preeclampsia (PE) is a pregnancy-specific condition featured by high blood pressure, edema, and proteinuria. Research about the role of microRNA (miR)-203 in PE remains insufficient. This experiment is designed to investigate the specific role of miR-203 in trophoblasts in PE.

STUDY DESIGN

 miR-203 expression in placenta tissues of normal pregnant women and PE patients was examined to analyze the relevance between miR-203 and PE diagnostic efficiency and between miR-203 and blood pressure (systolic pressure and diastolic pressure) and proteinuria of PE patients. miR-203 expression was downregulated in hypoxia-cultured trophoblasts using miR-203 inhibitor to assess matrix metalloproteinase-9 (MMP-9) level. Then, the angiogenesis of trophoblasts with different treatments was determined. Subsequently, the target relation between miR-203 and insulin-like growth factor receptor 1 (IGF-1R) was predicted and verified. Additionally, the effect of IGF-1R in the mechanism of miR-203 modulating trophoblast vascular remodeling was detected.

RESULTS

 miR-203 was overexpressed in the placenta of PE patients and it acted as a promising diagnostic indicator for PE. Moreover, miR-203 was positively associated with blood pressure (systolic pressure and diastolic pressure) and proteinuria of PE patients. miR-203 silencing in hypoxia-cultured trophoblasts enhanced trophoblast vascular remodeling. Mechanically, miR-203 bound to IGF-1R to suppress its transcription. IGF-1R downregulation counteracted the promotive effect of miR-203 silencing on trophoblast vascular remodeling.

CONCLUSION

 miR-203 was overexpressed in PE, and it targeted IGF-1R to limit trophoblast vascular remodeling.

KEY POINTS

· miR-203 is overexpressed in the placenta of PE patients.. · miR-203 acts as a potential diagnostic marker for PE.. · miR-203 targets IGF-1R to reduce trophoblast vascular remodeling in PE..

N6-methyladenosine (m6A) Modification in Preeclampsia

Recently, epitranscriptional modification of N6-methyladenosine (m6A) has received growing attention in the research on the pathogenesis of preeclampsia. Advances in m6A sequencing have revealed the molecular mechanism and importance of m6A modification. In addition, epitranscriptional modification of m6A is closely related to the metabolic processes of placental tissues and cells in preeclampsia. This article reviews the composition, mode of action, and bioinformatics analysis of m6A modification-related proteins, and their biological function in the progression of preeclampsia. The relationship between m6A modification and preeclampsia risk factors, such as diabetes, cardiovascular disease, obesity, and psychological stress, is summarized to provide new ideas for studying PE-targeting molecules.

Biogenesis and function of exosome lncRNAs and their role in female pathological pregnancy

Preeclampsia, gestational diabetes mellitus, and recurrent spontaneous abortion are common maternal pregnancy complications that seriously endanger women's lives and health, and their occurrence is increasing year after year with a rejuvenation trend. In contrast to biomarkers found freely in tissues or body fluids, exosomes exist in a relatively independent environment and provide a higher level of stability. As backbone molecules, guidance molecules, and signaling molecules in the nucleus, lncRNAs can regulate gene expression. In the cytoplasm, lncRNAs can influence gene expression levels by modifying mRNA stability, acting as competitive endogenous RNAs to bind miRNAs, and so on. Exosomal lncRNAs can exist indefinitely and are important in intercellular communication and signal transduction. Changes in maternal serum exosome lncRNA expression can accurately and timely reflect the progression and regression of pregnancy-related diseases. The purpose of this paper is to provide a reference for clinical research on the pathogenesis, diagnosis, and treatment methods of pregnancy-related diseases by reviewing the role of exosome lncRNAs in female pathological pregnancy and related molecular mechanisms.

Long non-coding RNA TLR8-AS1 induces preeclampsia through increasing TLR8/STAT1 axis

OBJECTIVE

Our current study tried to assay the role of long noncoding RNAs (lncRNAs) TLR8-AS1 in regulating preeclampsia.

METHODS

TLR8-AS1 expression was examined in the clinical placental tissues of preeclampsia patients and the trophoblast cells induced by lipopolysaccharide (LPS). Then, different lentivirus was infected into trophoblast cells to study the role of TLR8-AS1 in cell functions. Furthermore, interactions among TLR8-AS1, signal transducer and activator of transcription 1 (STAT1) and toll-like receptor 8 (TLR8) were determined. A rat model of preeclampsia induced by N(omega)-nitro-L-arginine methyl ester was developed to validate the in-vitro findings.

RESULTS

High expression of TLR8-AS1 was detected in placental tissues of preeclampsia patients and LPS-induced trophoblast cells. In addition, overexpression of TLR8-AS1 arrested the proliferation, migration and invasion of trophoblast cells, which was related to the upregulation of TLR8 expression. Mechanistically, TLR8-AS1 recruited STAT1 to bind to the TLR8 promoter region, and thus promoted the transcription of TLR8. Meanwhile, overexpression of TLR8-AS1 was shown to aggravate preeclampsia by elevating TLR8 in vivo .

CONCLUSION

Our study confirmed that TLR8-AS1 aggravated the progression of preeclampsia through increasing the expression of STAT1 and TLR8.

A comprehensive overview of exosome lncRNAs: emerging biomarkers and potential therapeutics in endometriosis

Endometriosis is a gynecological condition that significantly impacting women's daily lives. In recent years, the incidence of endometriosis has been rising yearly and is now an essential contributor to female infertility. Exosomes are extracellular vesicles (EVs) that carry long noncoding RNA (lncRNA) and shield lncRNA from the outside environment thanks to their vesicle-like structure. The role of exosome-derived lncRNAs in endometriosis is also receiving more study as high-throughput sequencing technology develops. Several lncRNAs with variable expression may be crucial to the emergence and growth of endometriosis. The early diagnosis of endometriosis will be considerably improved by further high specificity and sensitivity Exosome lncRNA screening. Exosomes assist lncRNAs in carrying out their roles, offering a new target for creating endometriosis-specific medications. In order to serve as a reference for clinical research on the pathogenesis, diagnosis, and treatment options of endometriosis, this paper covers the role of exosome lncRNAs in endometriosis and related molecular mechanisms.

Hsa_circ_0088196 suppresses trophoblast migration and invasion by the miR-525-5p/ABL1 axis and the PI3K/AKT signaling pathway

Our study aimed to explore the role of circ_0088196 (circular TNC [circTNC]) in trophoblast invasion and migration in preeclampsia (PE) both in vitro and in vivo. CircTNC, miR-525-5p, and ABL1 expression in trophoblast HTR8/SVneo cells were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR). Cell viability, migration, and invasion were detected by Cell Counting Kit-8 (CCK-8), wound healing, and Transwell assays. The binding between circTNC (or ABL1) and miR-525-5p was validated by RNA pulldown and luciferase reporter assays. The mouse model of PE was injected with sh-circTNC and the effects of circTNC knockdown on the mean artery pressure, urine protein concentration, and fetal survival number of pregnant mice were examined. The expression of MMP-2, MMP-9, and PI3K/AKT pathway molecules in placental tissues was assessed by immunohistochemistry, qRT-PCR, and western blot analysis. CircTNC overexpression inhibited cell invasion and migration, but did not influence cell proliferation. CircTNC bound with miR-525-5p, whose knockdown repressed cell invasion and migration, while it exerted no effect on cell proliferation. ABL1, a target of miR-525-5p, attenuated cell migration and invasion, without influence on cell viability. Importantly, either miR-525-5p overexpression or ABL1 depletion antagonized the repression of upregulated circTNC on trophoblast cell migration and invasion, MMP-2 and MMP-9 expression, and the PI3K/AKT pathway. CircTNC knockdown alleviated PE symptoms in pregnant mice. CircTNC knockdown promoted the trophoblast invasiveness in mice placenta by upregulating MMP-2/9 expression and suppressing the PI3K/AKT pathway. Circ_0088196 represses trophoblast invasion and migration both in vitro and in vivo via regulating the miR-525-5p/ABL1 axis and activating the PI3K/AKT pathway.

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

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

Hypoxia induced-disruption of lncRNA TUG1/PRC2 interaction impairs human trophoblast invasion through epigenetically activating Nodal/ALK7 signalling

Inadequate trophoblastic invasion is considered as one of hallmarks of preeclampsia (PE), which is characterized by newly onset of hypertension (>140/90 mmHg) and proteinuria (>300 mg in a 24‐h urine) after 20 weeks of gestation. Accumulating evidence has indicated that long noncoding RNAs are aberrantly expressed in PE, whereas detailed mechanisms are unknown. In the present study, we showed that lncRNA Taurine upregulated 1 (TUG1) were downregulated in preeclamptic placenta and in HTR8/SVneo cells under hypoxic conditions, together with reduced enhancer of zeste homolog2 (EZH2) and embryonic ectoderm development (EED) expression, major components of polycomb repressive complex 2 (PRC2), as well as activation of Nodal/ALK7 signalling pathway. Mechanistically, we found that TUG1 bound to PRC2 (EZH2/EED) in HTR8/SVneo cells and weakened TUG1/PRC2 interplay was correlated with upregulation of Nodal expression via decreasing H3K27me3 mark at the promoter region of Nodal gene under hypoxic conditions. And activation of Nodal signalling prohibited trophoblast invasion via reducing MMP2 levels. Overexpression of TUG1 or EZH2 significantly attenuated hypoxia‐induced reduction of trophoblastic invasiveness via negative modulating Nodal/ALK7 signalling and rescuing expression of its downstream target MMP2. These investigations might provide some evidence for novel mechanisms responsible for inadequate trophoblastic invasion and might shed some light on identifying future therapeutic targets for PE.

Small Non-Coding RNAs in the Human Placenta: Regulatory Roles and Clinical Utility

The placenta is a vital organ formed during pregnancy, and being the interface between the mother and fetus, it is paramount that placental functioning is strictly controlled. Gene expression in the placenta is finely tuned-with aberrant expression causing placental pathologies and inducing stress on both mother and fetus. Gene regulation is brought upon by several mechanisms, and small non-coding RNAs (sncRNAs) have recently been appreciated for their contribution in gene repression. Their dysregulation has been implicated in a range of somatic and inherited disorders, highlighting their importance in maintaining healthy organ function. Their specific roles within the placenta, however, are not well understood, and require further exploration. To this end, we summarize the mechanisms of microRNAs (miRNAs), Piwi-interacting RNAs (piRNAs), small nuclear RNAs (snRNAs), small nucleolar RNAs (snoRNAs), and transfer RNAs (tRNAs), their known contributions to human placental health and disease, the relevance of sncRNAs as promising biomarkers throughout pregnancy, and the current challenges faced by placental sncRNA studies.

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.