MiR-125b participates in the occurrence of preeclampsia by regulating the migration and invasion of extravillous trophoblastic cells through STAT3 signaling pathway

First Trimester Placental Biomarkers for Pregnancy Outcomes

The placenta plays a key role in several adverse obstetrical outcomes, such as preeclampsia, intrauterine growth restriction and gestational diabetes mellitus. The early identification of at-risk pregnancies could significantly improve the management, therapy and prognosis of these pregnancies, especially if these at-risk pregnancies are identified in the first trimester. The aim of this review was to summarize the possible biomarkers that can be used to diagnose early placental dysfunction and, consequently, at-risk pregnancies. We divided the biomarkers into proteins and non-proteins. Among the protein biomarkers, some are already used in clinical practice, such as the sFLT1/PLGF ratio or PAPP-A; others are not yet validated, such as HTRA1, Gal-3 and CD93. In the literature, many studies analyzed the role of several protein biomarkers, but their results are contrasting. On the other hand, some non-protein biomarkers, such as miR-125b, miR-518b and miR-628-3p, seem to be linked to an increased risk of complicated pregnancy. Thus, a first trimester heterogeneous biomarkers panel containing protein and non-protein biomarkers may be more appropriate to identify and discriminate several complications that can affect pregnancies.

Non-coding RNA regulates the immune microenvironment in recurrent spontaneous abortion (RSA): new insights into immune mechanisms†

Recurrent spontaneous abortion (RSA) has various causes, including chromosomal abnormalities, prethrombotic state, and abnormal uterine anatomical factors. However, the pathogenesis of RSA is still unclear. Surprisingly, non-coding RNA can stably express at the maternal-fetal interface and regulate immune cells' proliferation, apoptosis, invasion, metastasis, and angiogenesis. Accumulating evidence suggests that the competing endogenous RNA (ceRNA) regulatory network between non-coding RNAs complicates RSA's pathological process and maybe a new starting point for exploring RSA. In this review, we mainly discuss the regulatory network and potential significance of non-coding RNA in the immune microenvironment of RSA patients. In addition, the cellular interactions of non-coding RNA transported through vesicles were introduced from aspects of trophoblast function and immune regulation. Finally, we analyze previous studies and further discuss that the stable expression of non-coding RNA may be used as a biomarker of some disease states and a prediction target of RSA.

Research progress on the STAT signaling pathway in pregnancy and pregnancy-associated disorders

Signal transducer and activator of transcription (STAT) proteins, pivotal regulators of signaling cascades, undergo activation in response to the stimulation of cytokines and growth factors, and participate in biological processes, including inflammation, immune responses, cell proliferation, and differentiation. During the process of pregnancy, STAT signaling is involved in regulating embryonic implantation, endometrial decidualization, and establishing and maintaining maternal-fetal immune tolerance. Increasing evidence suggests that aberrant STAT signaling contributes to the occurrence and development of pregnancy disorders, including repeated implantation failure (RIF), preeclampsia (PE), recurrent spontaneous abortion (RSA), preterm birth (PTB) and gestational diabetes mellitus (GDM). Elucidating the molecular mechanisms of the STAT signaling pathway holds promise for further understanding the establishment and maintenance of normal pregnancy, and thereby providing potent targets and strategic avenues for the prevention and management of ailments associated with pregnancy. In this review, we summarized the roles of the STAT signaling pathway and its related regulatory function in embryonic implantation, endometrial decidualization, and maternal-fetal immune tolerance. In conclusion, in-depth research on the mechanism of the STAT signaling pathway not only enhances our understanding of normal pregnancy processes but also offers STAT-based therapeutic approaches to protect women from the burden of pregnancy-related disorders.

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.

Placenta-derived exosomes as carriers of non-coding RNAs in maternal circulation of patients with preeclampsia

This study was conducted to illustrate the origin of these PE-related ncRNAs in maternal circulation and their underlying transport methods into target cells. We selected 10 women with severe pre-eclampsia (PE group) and 10 healthy participants who served as controls (NC group). Exosomes were isolated from their sera and their origin was determined by a specific marker, placental alkaline phosphatase (PLAP). We compared the ncrna associated with PE in exosomes and whole serum to observe the exchange of serum exosomes with trophoblast cells. The results showed that PLAP was enriched in the isolated exosomes. Seven PE-associated ncRNAs, including lnc-SNHG5, miR-26a-5p, miR-221-3p, miR-30a-3p, miR-18a, miR-152 and miR-155, were analyzed in placenta-derived exosomes and whole serum from both groups. miR-26a-5p, miR-152 and miR-155 were upregulated in the PE group compared with the NC group. 152 and miR-155 were upregulated. 152 and miR-155 were upregulated, while miR-18a and miR-221-3p were downregulated (P<0.05). ncRNAs were altered in serum and placenta-derived serum exosomes in a consistent trend. Fluorescence microscopy results showed that the nuclei were counterstained in HTR-8 cells exposed to PKH26-labeled exosomes. PE-associated ncRNAs can enter the maternal circulation through secretion and encapsulation into placenta-derived exosomes and participate in the development and progression of PE by targeting trophoblast cells. differential expression of ncRNAs in exosomes has the potential to be used as predictors for targeted therapy, providing new ideas and perspectives for improving maternal and infant outcomes.

Role of microRNAs in trophoblast invasion and spiral artery remodeling: Implications for preeclampsia

It is now well-established that microRNAs (miRNAs) are important regulators of gene expression. The role of miRNAs in placental development and trophoblast function is constantly expanding. Trophoblast invasion and their ability to remodel uterine spiral arteries are essential for proper placental development and successful pregnancy outcome. Many miRNAs are reported to be dysregulated in pregnancy complications, especially preeclampsia and they exert various regulatory effects on trophoblasts. In this review, we provide a brief overview of miRNA biogenesis and their mechanism of action, as well as of trophoblasts differentiation, invasion and spiral artery remodeling. We then discuss the role of miRNAs in trophoblasts invasion and spiral artery remodeling, focusing on miRNAs that have been thoroughly investigated, especially using multiple model systems. We also discuss the potential role of miRNAs in the pathogenesis of preeclampsia.

NINJ1 triggers extravillous trophoblast cell dysfunction through blocking the STAT3 signaling pathway

BACKGROUND

Trophoblasts are the most important parts of the placenta in early pregnancy. Trophoblast cell dysfunction can induce embryo implantation insufficiency, thereby resulting in multiple diseases, including recurrent spontaneous abortion (RSA). A previous study indicates higher nerve injury-induced protein 1 (NINJ1) RNA levels in the villi tissues of RSA patients.

OBJECTIVE

This study aimed to investigate the effect of NINJ1 on trophoblast behaviors and pregnancy loss.

METHODS

Fresh villi tissues were obtained from with RSA patients and patients with artificial selective abortion for personal reasons, and NINJ1 expression in these tissues was detected. Extravillous trophoblast cell line HTR-8/SVneo was transfected with small-interfering RNA targeting NINJ1 or NINJ1 overexpression vector to perform loss-/gain-of-function experiments. Spontaneous abortion (SA) was induced by mating CBA/J females with DBA/2 males and the pregnant females were intraperitoneally injected with adenovirus vector carrying NINJ1 short hairpin RNA.

RESULTS

NINJ1 mRNA and protein levels were higher in the villi tissues of RSA patients than those of artificial selective abortion patients. NINJ1 knockdown promoted trophoblast cell proliferation, migration and invasion but inhibited cell apoptosis. Moreover, conditioned medium from NINJ1-depleted trophoblasts promoted the angiogenesis of human umbilical vein endothelial cells. NINJ1 knockdown also promoted activation of the signal transducer and activator of transcription 3 (STAT3) signaling pathway in trophoblasts, and STAT3 inhibitor reversed NINJ1 knockdown-induced effects on trophoblast behaviors. Furthermore, pregnancy loss was attenuated by NINJ1 inhibition.

CONCLUSION

NINJ1 contributes to the development of SA and triggers trophoblast cell dysfunction through inhibiting the STAT3 pathway.

Micro-RNAs in Human Placenta: Tiny Molecules, Immense Power

Micro-RNAs (miRNAs) are short non-coding single-stranded RNAs that modulate the expression of various target genes after transcription. The expression and distribution of kinds of miRNAs have been characterized in human placenta during different gestational stages. The identified miRNAs are recognized as key mediators in the regulation of placental development and in the maintenance of human pregnancy. Aberrant expression of miRNAs is associated with compromised pregnancies in humans, and dysregulation of those miRNAs contributes to the occurrence and development of related diseases during pregnancy, such as pre-eclampsia (PE), fetal growth restriction (FGR), gestational diabetes mellitus (GDM), recurrent miscarriage, preterm birth (PTB) and small-for-gestational-age (SGA). Thus, having a better understanding of the expression and functions of miRNAs in human placenta during pregnancy and thereby developing novel drugs targeting the miRNAs could be a potentially promising method in the prevention and treatment of relevant diseases in future. Here, we summarize the current knowledge of the expression pattern and function regulation of miRNAs in human placental development and related diseases.

Regulatory roles of non-coding RNAs and m6A modification in trophoblast functions and the occurrence of its related adverse pregnancy outcomes

Adverse pregnancy outcomes, such as preeclampsia, gestational diabetes mellitus, fetal growth restriction, and recurrent miscarriage, occur frequently in pregnant women and might further induce morbidity and mortality for both mother and fetus. Increasing studies have shown that dysfunctions of human trophoblast are related to these adverse pregnancy outcomes. Recent studies also showed that environmental toxicants could induce trophoblast dysfunctions. Moreover, non-coding RNAs (ncRNAs) have been reported to play important regulatory roles in various cellular processes. However, the roles of ncRNAs in the regulation of trophoblast dysfunctions and the occurrence of adverse pregnancy outcomes still need to be further investigated, especially with exposure to environmental toxicants. In this review, we analyzed the regulatory mechanisms of ncRNAs and m6A methylation modification in the dysfunctions of trophoblast cells and the occurrence of adverse pregnancy outcomes and also summarized the harmful effects of environmental toxicants. In addition to DNA replication, mRNA transcription, and protein translation, ncRNAs and m6A modification might be considered as the fourth and fifth elements that regulate the genetic central dogma, respectively. Environmental toxicants might also affect these processes. In this review, we expect to provide a deeper scientific understanding of the occurrence of adverse pregnancy outcomes and to discover potential biomarkers for the diagnosis and treatment of these outcomes.

RAR-Related Orphan Receptor: An Accelerated Preeclampsia Progression by Activating the JAK/STAT3 Pathway

PURPOSE

To investigate the effect and underlying mechanism of RAR related orphan receptor A (RORA) on preeclampsia (PE).

MATERIALS AND METHODS

Differentially expressed genes (DEGs) in four datasets were obtained by using the Venn diagram method. RORA mRNA and protein expressions were detected by qRT-PCR, western blot, and immunohistochemistry. HTR-8/SVneo cell viability, proliferation, invasion, migration, and angiogenesis were detected by CCK-8 assay, EdU assay, Transwell, wound healing assay, and tube formation assay, respectively. The concentration of Ang-1 in cells was assessed using available ELISA kit. Epithelial-mesenchymal transition, proliferation, and angiogenesis-related proteins were detected by western blot. GSEA analysis were performed for common DEGs, and the expression of enriched pathway-related proteins was also detected.

RESULTS

The expression of RORA was increased in PE tissue and HTR-8/SVneo cells. Silencing RORA could promote the migration, invasion, epithelial-mesenchymal transition, proliferation, and angiogenesis of hypoxia-treated HTR-8/SVneo cells. Mechanistically, RORA contributed to the deterioration of PE by activating the JAK2/STAT3 signaling pathway to promote cell proliferation, migration, invasion, and angiogenesis.

CONCLUSION

RORA was up-regulated in PE and affected HTR-8/SVneo cell proliferation, invasion, migration, apoptosis, and angiogenesis via the JAK2/STAT3 signaling pathway. This provided a novel strategy for the prevention and treatment of PE.

Roles of noncoding RNAs in preeclampsia

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

Integrated bioinformatics analysis reveals novel key biomarkers and potential candidate small molecule drugs in gestational diabetes mellitus

Gestational diabetes mellitus (GDM) is the metabolic disorder that appears during pregnancy. The current investigation aimed to identify central differentially expressed genes (DEGs) in GDM. The transcription profiling by array data (E-MTAB-6418) was obtained from the ArrayExpress database. The DEGs between GDM samples and non-GDM samples were analyzed. Functional enrichment analysis were performed using ToppGene. Then we constructed the protein–protein interaction (PPI) network of DEGs by the Search Tool for the Retrieval of Interacting Genes database (STRING) and module analysis was performed. Subsequently, we constructed the miRNA–hub gene network and TF–hub gene regulatory network. The validation of hub genes was performed through receiver operating characteristic curve (ROC). Finally, the candidate small molecules as potential drugs to treat GDM were predicted by using molecular docking. Through transcription profiling by array data, a total of 869 DEGs were detected including 439 up-regulated and 430 down-regulated genes. Functional enrichment analysis showed these DEGs were mainly enriched in reproduction, cell adhesion, cell surface interactions at the vascular wall and extracellular matrix organization. Ten genes, HSP90AA1, EGFR, RPS13, RBX1, PAK1, FYN, ABL1, SMAD3, STAT3 and PRKCA were associated with GDM, according to ROC analysis. Finally, the most significant small molecules were predicted based on molecular docking. This investigation identified hub genes, signal pathways and therapeutic agents, which might help us, enhance our understanding of the mechanisms of GDM and find some novel therapeutic agents for GDM.

Non-Coding RNAs Regulate Placental Trophoblast Function and Participate in Recurrent Abortion

Recurrent spontaneous abortion (RSA) is a serious pregnancy complication with an increasing clinical incidence. The various causes of recurrent abortion are complicated. Developments in genetics, immunology, and cell biology have identified important roles of non-coding RNAs (ncRNAs) in the occurrence and progress of recurrent abortion. NcRNAs can affect the growth, migration, and invasion of placental trophoblasts by regulating cell processes such as the cell cycle, apoptosis, and epithelial-mesenchymal transformation. Therefore, their abnormal expression might lead to the occurrence and development of RSA. NcRNAs include small nuclear RNA (snRNA), small nucleolar RNA (snoRNA), ribosomal RNA (rRNA), transfer, RNA (tRNA), circular RNA (cRNA), and Piwi-interacting RNA (piRNA). In this review, we discuss recent research that focused on the function and mechanism of microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNA (circRNA) in regulating placental trophoblasts. The use of ncRNAs as potential diagnostic and predictive biomarkers in RSA is also discussed to provide future research insights.