Bioinformatics approach reveals the critical role of TGF-β signaling pathway in pre-eclampsia development

TGFβ signalling: a nexus between inflammation, placental health and preeclampsia throughout pregnancy

BACKGROUND

The placenta is a unique and pivotal organ in reproduction, controlling crucial growth and cell differentiation processes that ensure a successful pregnancy. Placental development is a tightly regulated and dynamic process, in which the transforming growth factor beta (TGFβ) superfamily plays a central role. This family of pleiotropic growth factors is heavily involved in regulating various aspects of reproductive biology, particularly in trophoblast differentiation during the first trimester of pregnancy. TGFβ signalling precisely regulates trophoblast invasion and the cell transition from cytotrophoblasts to extravillous trophoblasts, which is an epithelial-to-mesenchymal transition-like process. Later in pregnancy, TGFβ signalling ensures proper vascularization and angiogenesis in placental endothelial cells. Beyond its role in trophoblasts and endothelial cells, TGFβ signalling contributes to the polarization and function of placental and decidual macrophages by promoting maternal tolerance of the semi-allogeneic foetus. Disturbances in early placental development have been associated with several pregnancy complications, including preeclampsia (PE) which is one of the severe complications. Emerging evidence suggests that TGFβ is involved in the pathogenesis of PE, thereby offering a potential target for intervention in the human placenta.

OBJECTIVE AND RATIONALE

This comprehensive review aims to explore and elucidate the roles of the major members of the TGFβ superfamily, including TGFβs, bone morphogenetic proteins (BMPs), activins, inhibins, nodals, and growth differentiation factors (GDFs), in the context of placental development and function. The review focusses on their interactions within the major cell types of the placenta, namely trophoblasts, endothelial cells, and immune cells, in both normal pregnancies and pregnancies complicated by PE throughout pregnancy.

SEARCH METHODS

A literature search was carried out using PubMed and Google Scholar, searching terms: 'TGF signalling preeclampsia', 'pregnancy TGF signalling', 'preeclampsia tgfβ', 'preeclampsia bmp', 'preeclampsia gdf', 'preeclampsia activin', 'endoglin preeclampsia', 'endoglin pregnancy', 'tgfβ signalling pregnancy', 'bmp signalling pregnancy', 'gdf signalling pregnancy', 'activin signalling pregnancy', 'Hofbauer cell tgfβ signalling', 'placental macrophages tgfβ', 'endothelial cells tgfβ', 'endothelium tgfβ signalling', 'trophoblast invasion tgfβ signalling', 'trophoblast invasion Smad', 'trophoblast invasion bmp', 'trophoblast invasion tgfβ', 'tgfβ preeclampsia', 'tgfβ placental development', 'TGFβ placental function', 'endothelial dysfunction preeclampsia tgfβ signalling', 'vascular remodelling placenta TGFβ', 'inflammation pregnancy tgfβ', 'immune response pregnancy tgfβ', 'immune tolerance pregnancy tgfβ', 'TGFβ pregnancy NK cells', 'bmp pregnancy NK cells', 'bmp pregnancy tregs', 'tgfβ pregnancy tregs', 'TGFβ placenta NK cells', 'TGFβ placenta tregs', 'NK cells preeclampsia', 'Tregs preeclampsia'. Only articles published in English until 2023 were used.

OUTCOMES

A comprehensive understanding of TGFβ signalling and its role in regulating interconnected cell functions of the main placental cell types provides valuable insights into the processes essential for successful placental development and growth of the foetus during pregnancy. By orchestrating trophoblast invasion, vascularization, immune tolerance, and tissue remodelling, TGFβ ligands contribute to the proper functioning of a healthy maternal-foetal interface. However, dysregulation of TGFβ signalling has been implicated in the pathogenesis of PE, where the shallow trophoblast invasion, defective vascular remodelling, decreased uteroplacental perfusion, and endothelial cell and immune dysfunction observed in PE, are all affected by an altered TGFβ signalling.

WIDER IMPLICATIONS

The dysregulation of TGFβ signalling in PE has important implications for research and clinical practice. Further investigation is required to understand the underlying mechanisms, including the role of different ligands and their regulation under pathophysiological conditions, in order to discover new therapeutic targets. Distinguishing between clinically manifested subtypes of PE and studying TGFβ signalling in different placental cell types holistically is an important first step. To put this knowledge into practice, pre-clinical animal models combined with new technologies are needed. This may also lead to improved human research models and identify potential therapeutic targets, ultimately improving outcomes for affected pregnancies and reducing the burden of PE.

MicroRNA analysis of medium/large placenta extracellular vesicles in normal and preeclampsia pregnancies

Background

Preeclampsia (PE) is a hypertensive disorder of pregnancy, affecting 2%-8% of pregnancies worldwide, and is the leading cause of adverse maternal and fetal outcomes. The disease is characterized by oxidative and cellular stress and widespread endothelial dysfunction. While the precise mechanisms are not entirely understood, the pathogenesis of PE is closely linked to placental dysfunction and, to some extent, syncytiotrophoblast extracellular vesicle release (STB-EVs). These vesicles can be divided into the less well-studied medium/large EVs (220-1,000 nm) released in response to stress and small EVs (<220 nm) released as a component of intercellular communication. The previously described production of m/lSTB-EVs in response to cellular stress combined with the overwhelming occurrence of cellular and oxidative stress in PE prompted us to evaluate the microRNAome of PE m/lSTB-EVs. We hypothesized that the microRNAome profile of m/lSTB-EVs is different in PE compared to normal pregnancy (NP), which might permit the identification of potential circulating biomarkers not previously described in PE.

Methods/study design

We performed small RNA sequencing on medium/large STB-EVs isolated from PE and NP placentae using dual-lobe ex vivo perfusion. The sequencing data was bioinformatically analyzed to identify differentially regulated microRNAs. Identified microRNAs were validated with quantitative PCR analysis. We completed our analysis by performing an in-silico prediction of STB-EV mechanistic pathways.

Results

We identified significant differences between PE and NP in the STB-EVs micro ribonucleic acid (microRNA) profiles. We verified the differential expression of hsa-miR-193b-5p, hsa-miR-324-5p, hsa-miR-652-3p, hsa-miR-3196, hsa-miR-9-5p, hsa-miR-421, and hsa-miR-210-3p in the medium/large STB-EVs. We also confirmed the differential abundance of hsa-miR-9-5p in maternal serum extracellular vesicles (S EVs). In addition, we integrated the results of these microRNAs into the previously published messenger RNA (mRNA) data to better understand the relationship between these biomolecules.

Conclusions

We identified a differentially regulated micro-RNA, hsa-miR-9-5p, that may have biomarker potential and uncovered mechanistic pathways that may be important in the pathophysiology of PE.

CyPA interacts with SERPINH1 to promote extracellular matrix production and inhibit epithelial-mesenchymal transition of trophoblast via enhancing TGF-β/Smad3 pathway in preeclampsia

We previously reported that cyclophilin A (CyPA) production is upregulated in preeclampsia (PE). Moreover, CyPA is known to induce PE-like features in pregnant mice and impair trophoblast invasiveness. In this study, we further illustrated the role of CyPA in PE. RNA-seq analysis, RT-qPCR, immunohistochemical (IHC) staining, and western blotting of mouse placentae revealed that CyPA increased the levels of extracellular matrix (ECM) proteins, such as collagen I and fibronectin, and activated the TGF-β/Smad3 signaling pathway. Additionally, CyPA inhibited the expression of genes involved in epithelial-mesenchymal transition (EMT) (e.g., E-cadherin, N-cadherin, and vimentin) in mouse placentae. We then constructed stable overexpressing and knock-down CyPA cell models (using HTR8/SVneo cells) to clarify the molecular mechanism. We found that CyPA regulated the levels of ECM-related proteins and the EMT process through the TGF-β/Smad3 pathway. We also identified SERPINH1 as a putative CyPA-binding protein, using liquid chromatography-electrospray mass spectrometry (LC-MS)/MS. SERPINH1 was found to be upregulated in the placentae of PE. Silencing SERPINH1 expression reversed the upregulation of ECM proteins and inhibition of the EMT process induced by the overexpression of CyPA. These findings revealed the functions of CyPA in the impaired invasiveness of trophoblasts in PE and indicated that CyPA and SERPINH1 may represent promising targets for the treatment of PE.

Early-pregnancy prediction of risk for pre-eclampsia using maternal blood leptin/ceramide ratio: discovery and confirmation

OBJECTIVE

This study aimed to develop a blood test for the prediction of pre-eclampsia (PE) early in gestation. We hypothesised that the longitudinal measurements of circulating adipokines and sphingolipids in maternal serum over the course of pregnancy could identify novel prognostic biomarkers that are predictive of impending event of PE early in gestation.

STUDY DESIGN

Retrospective discovery and longitudinal confirmation.

SETTING

Maternity units from two US hospitals.

PARTICIPANTS

Six previously published studies of placental tissue (78 PE and 95 non-PE) were compiled for genomic discovery, maternal sera from 15 women (7 non-PE and 8 PE) enrolled at ProMedDx were used for sphingolipidomic discovery, and maternal sera from 40 women (20 non-PE and 20 PE) enrolled at Stanford University were used for longitudinal observation.

OUTCOME MEASURES

Biomarker candidates from discovery were longitudinally confirmed and compared in parallel to the ratio of placental growth factor (PlGF) and soluble fms-like tyrosine kinase (sFlt-1) using the same cohort. The datasets were generated by enzyme-linked immunosorbent and liquid chromatography-tandem mass spectrometric assays.

RESULTS

Our discovery integrating genomic and sphingolipidomic analysis identified leptin (Lep) and ceramide (Cer) (d18:1/25:0) as novel biomarkers for early gestational assessment of PE. Our longitudinal observation revealed a marked elevation of Lep/Cer (d18:1/25:0) ratio in maternal serum at a median of 23 weeks' gestation among women with impending PE as compared with women with uncomplicated pregnancy. The Lep/Cer (d18:1/25:0) ratio significantly outperformed the established sFlt-1/PlGF ratio in predicting impending event of PE with superior sensitivity (85% vs 20%) and area under curve (0.92 vs 0.52) from 5 to 25 weeks of gestation.

CONCLUSIONS

Our study demonstrated the longitudinal measurement of maternal Lep/Cer (d18:1/25:0) ratio allows the non-invasive assessment of PE to identify pregnancy at high risk in early gestation, outperforming the established sFlt-1/PlGF ratio test.

Identification of Key Molecules and lncRNA-miRNA-mRNA ceRNA Network in Preeclampsia

Background

Preeclampsia (PE) is an idiopathic hypertensive disorder of pregnancy and is the leading cause of maternal death, fetal malformation, and premature birth. The purpose of this study is to identify the key molecules and lncRNA-related competitive endogenous (ceRNA) regulatory network in PE.

Methods

The differentially expressed mRNAs (DEGs), lncRNAs (DELs), and miRNAs (DEMs) were identified between PE and control using the Deseq R package. In addition, we performed Geno ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) on DEGs and DELs-target genes to explore their function. The ceRNA network was established based on lncRNA-miRNA and miRNA-mRNA interactions and visualized using Cytoscape software. LINCO2532, SLCO4A1-AS1, miR23a-5p, and DYNLRB1 were selected for qRT-PCR assay.

Results

Using microarray analysis, we screened 726 DELs (456 upregulated and 370 downregulated), 49 DEMs (37 upregulated and 12 downregulated), and 318 DEGs (230 upregulated and 88 downregulated) between PE patients and control. Based on lncRNA-miRNA pairs and miRNA-mRNA pairs, the ceRNA network was constructed, which contained 16 lncRNA, 1 miRNA (miR-23a-5p), and 1 mRNA (DYNLRB1). LncRNA (LINCO2532 and SLCO4A1-AS1) and DYNLRB1 were downregulated and the expression of miR23a-5p was upregulated in PE patients compared with healthy controls.

Conclusion

In this study, the novel ceRNA network was established in the placentas of PE patients. It elucidated the regulatory mechanism of PE, and identified novel PE biomarkers, which have important guiding significance for clinical treatment and further scientific research of PE.

Screening and Identification of Hub Genes in the Corticosteroid Resistance Network in Human Airway Epithelial Cells via Microarray Analysis

Background and Objective: Corticosteroid resistance is a major barrier to chronic obstructive pulmonary disease (COPD), but the exact mechanism of corticosteroid resistance in COPD has been less well studied. Methods: The microarray dataset GSE11906, which includes genomic and clinical data on COPD, was downloaded from the Gene Expression Omnibus (GEO) database, and the differentially expressed genes (DEGs) were identified using R software. Gene set enrichment analysis (GSEA) and Kyoto Encyclopedia of Genes (KEGG) were utilized to enrich and analyze the gene cohort related to the response to steroid hormones, respectively. The Connectivity Map (CMap) database was used to screen corticosteroid resistance-related drugs that might exert a potential therapeutic effect. STRING was used to construct a protein-protein interaction (PPI) network of the gene cohort, and the CytoHubba plug-in of Cytoscape was used to screen the hub genes in the PPI network. The expression levels of hub genes in cigarette smoke extract (CSE)-stimulated bronchial epithelial cells were assayed by quantitative real-time PCR and western blotting. Results: Twenty-one genes were found to be correlated with the response to steroid hormones. In the CMap database, 32 small-molecule compounds that might exert a therapeutic effect on corticosteroid resistance in COPD were identified. Nine hub genes were extracted from the PPI network. The expression levels of the BMP4, FOS, FN1, EGFR, and SPP1 proteins were consistent with the microarray data obtained from molecular biology experiments. Scopoletin significantly restrained the increases in the levels of AKR1C3, ALDH3A1, FN1 and reversed the decreases of phosphorylated GR and HDAC2 caused by CSE exposure. Conclusion: The BMP4, FOS, FN1, EGFR, and SPP1 genes are closely correlated with CSE-induced glucocorticoid resistance in airway epithelial cells. Scopoletin may be a potential drug for the treatment of glucocorticoid resistance caused by CSE.

Exosomal mRNA and lncRNA profiles in cord blood of preeclampsia patients

BACKGROUND

Exosomes are endosome-derived membrane vesicles that contain numerous RNAs and allow intercellular communication. The roles of mRNAs and lncRNAs from umbilical cord blood exosomes in the development of preeclampsia (PE) remain unclear.

METHODS

In the study, microarray technology was used to construct the differential mRNA and lncRNA expression profiles in umbilical cord blood exosomes between PE patients and normal controls.

RESULTS

Totally, 120 differentially expressed mRNAs and 248 differentially expressed lncRNAs were identified. Pathway analysis showed that the differentially expressed mRNAs were related to glycolysis/gluconeogenesis, PI3K-Akt signaling pathway and JAK-STAT signaling pathway, which are critical in PE development. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were conducted for the differential lncRNA-associated mRNAs. We found several significantly enriched pathways were closely associated with metabolic process, cell proliferation, differentiation, and apoptosis. Moreover, the constructed pathway network revealed key pathways in PE, including apoptosis and TGF-beta signaling pathway. Further analysis of lncRNA/miRNA interactions showed that most of the lncRNAs had miRNA binding sites, and some of them were associated with PE.

CONCLUSIONS

The study highlights the importance of exosomal mRNAs and lncRNAs in umbilical cord blood, and provides new insight into the development of PE.

The COL-4A1 polypeptide destroy endothelial cells through the TGF-β/PI3K/AKT pathway

Preeclampsia (PE) is commonly considered as a placental disorder in pregnancy. Until now, the etiology and pathological mechanism of PE have remained ambiguous. Although PE can lead to a variety of maternal and infant complications, there are still no effective treatments. This study aimed to explore the correlation between the novel polypeptide COL-4A1 and PE, and to identify the underlying mechanism by which this polypeptide may function and to explore new therapeutic targets for PE. A rat model of PE was established and used to verify the function of the polypeptide COL-4A1 in vivo. Additionally, human umbilical vascular endothelial cells (HUVECs) were cultured with or without COL-4A1 and TNF-α (20 ng/ml). Cell Counting Kit-8 (CCK-8), wound-healing, Transwell and tube formation assays were used to evaluate cell proliferation, migration and angiopoiesis. RNA sequencing and mass spectrometry were conducted to explore the underlying downstream mechanism of COL-4A1. In vivo, COL-4A1 increased blood pressure and elevated the risk of fetal growth restriction (FGR) which was induced by lipopolysaccharide (LPS) in the rat model. In vitro, COL-4A1 significantly inhibited the proliferation and migration of HUVECs. After culture with COL-4A1, compared to control group the adhesive ability and level of reactive oxygen species (ROS) were enhanced and tube formation ability was decreased. Furthermore, Western blotting (WB) and pull-down assays were conducted to explore the underlying mechanism by which COL-4A1 functions, and the TGF-β/PI3K/AKT pathway was identified as the potential pathway involved in its effects. In summary, these results revealed that the polypeptide COL-4A1 caused PE-like symptoms in cells and a rat model. Through the TGF-β/PI3K/AKT pathway, COL-4A1 interferes with the pathogenesis of PE. Thus COL-4A1 is expected to become a potential target of PE, providing a basis for exploring the treatment of PE.

Induction of TGF-β receptor I expression in a DNA methylation-independent manner mediated by DNMT3A downregulation is involved in early-onset severe preeclampsia

Preeclampsia, especially early-onset severe preeclampsia is one of the leading causes of maternal and fetal morbidity and mortality. Although it has been well known that the pathophysiology of early-onset severe preeclampsia begins with abnormal placentation and aberrant activation of TGF-β signaling inhibits trophoblast cell invasion, the mechanisms underlying dysregulation of TGF-β signaling in early-onset severe preeclampsia remain elusive to date. Here, we revealed that induction of TGFBR1/TGF-β signaling mediated by DNMT3A downregulation plays a critical role in early-onset severe preeclampsia. Our results show that DNMT3A downregulation elevates TGFBR1 expression in trophoblast cells. Moreover, inhibition of TGFBR1 and TGF-β/Smad signaling can rescue the deficiencies of trophoblast cell migration and invasion caused by DNMT3A knockdown. Mechanistically, DNMT3A suppresses the transcription of TGFBR1 through recruiting EZH2 to its promoter but not changing DNA methylation of TGFBR1 promoter. In human samples, we detected lowly expressed DNMT3A, highly expressed TGFBR1 and hyperactivation of TGF-β/Smad signaling in decidua-embedded extravillous trophoblasts in early-onset severe preeclampsia, which provides the clinical evidence for the correlation between DNMT3A and TGFBR1. Collectively, our findings demonstrate that DNA methylation-independent induction of TGFBR1 mediated by DNMT3A downregulation is relevant to the development of early-onset severe preeclampsia.

The TGFβ Family in Human Placental Development at the Fetal-Maternal Interface

Emerging data suggest that a trophoblast stem cell (TSC) population exists in the early human placenta. However, in vitro stem cell culture models are still in development and it remains under debate how well they reflect primary trophoblast (TB) cells. The absence of robust protocols to generate TSCs from humans has resulted in limited knowledge of the molecular mechanisms that regulate human placental development and TB lineage specification when compared to other human embryonic stem cells (hESCs). As placentation in mouse and human differ considerably, it is only with the development of human-based disease models using TSCs that we will be able to understand the various diseases caused by abnormal placentation in humans, such as preeclampsia. In this review, we summarize the knowledge on normal human placental development, the placental disease preeclampsia, and current stem cell model systems used to mimic TB differentiation. A special focus is given to the transforming growth factor-beta (TGFβ) family as it has been shown that the TGFβ family has an important role in human placental development and disease.