Circ_0011460 upregulates HTRA1 expression by sponging miR-762 to suppress HTR8/SVneo cell growth, migration, and invasion

BACKGROUND

Aberrant expression of circular RNAs (circRNAs) during placental development could affect fetal growth and contribute to preeclampsia (PE). Circ_0011460 was found to be differentially expressed in placental samples of PE. However, the exact function and mechanism of circ_0011460 in PE process remain largely undefined.

METHODS

Levels of circ_0011460, microRNA (miR)-762, and high-temperature requirement-A serine peptidase 1 (HTRA1) were detected using quantitative real-time polymerase chain reaction and Western blot. In vitro experiments in HTR8/SVneo cells were conducted using cell counting kit-8, wound healing, transwell, flow cytometry and Western blot assays. The direct interactions between miR-762 and circ_0011460 or HTRA1 were verified using dual-luciferase reporter, RNA immunoprecipitation (RIP) and RNA pull-down assays.

RESULTS

Circ_0011460 possessed a loop structure and was highly expressed in placental tissues of PE patients. Overexpression of circ_0011460 greatly suppressed HTR8/SVneo cell proliferation, migration, and invasion, and accelerated cell apoptosis. While circ_0011460 knockdown yielded the opposite trends on above biological behaviors. Mechanistically, we confirmed that circ_0011460 could up-regulate HTRA1 expression via serving as a sponge of miR-762. Further rescue studies demonstrated that circ_0011460 exerted its roles via targeting miR-762, and miR-762 promoted HTR8/SVneo cell growth, migration and invasion via regulating HTRA1.

CONCLUSION

In all, circ_0011460 suppressed HTR8/SVneo cell growth, migration, and invasion via miR-762/HTRA1 axis, suggesting a new insight into the pathogenesis of PE.

NLRP3 Activation and Its Relationship to Endothelial Dysfunction and Oxidative Stress: Implications for Preeclampsia and Pharmacological Interventions

Preeclampsia (PE) is a specific syndrome of human pregnancy, being one of the main causes of maternal death. Persistent inflammation in the endothelium stimulates the secretion of several inflammatory mediators, activating different signaling patterns. One of these mechanisms is related to NLRP3 activation, initiated by high levels of danger signals such as cholesterol, urate, and glucose, producing IL-1, IL-18, and cell death by pyroptosis. Furthermore, reactive oxygen species (ROS), act as an intermediate to activate NLRP3, contributing to subsequent inflammatory cascades and cell damage. Moreover, increased production of ROS may elevate nitric oxide (NO) catabolism and consequently decrease NO bioavailability. NO has many roles in immune responses, including the regulation of signaling cascades. At the site of inflammation, vascular endothelium is crucial in the regulation of systemic inflammation with important implications for homeostasis. In this review, we present the important role of NLRP3 activation in exacerbating oxidative stress and endothelial dysfunction. Considering that the causes related to these processes and inflammation in PE remain a challenge for clinical practice, the use of drugs related to inhibition of the NLRP3 may be a good option for future solutions for this disease.

Irisin Protects the Human Placenta from Oxidative Stress and Apoptosis via Activation of the Akt Signaling Pathway

Irisin is a newly discovered exercise-mediated polypeptide hormone. Irisin levels increase during pregnancy however, women with preeclampsia (PE) have significantly lower levels of Irisin compared to women of healthy pregnancies. Even though many studies suggest a role of Irisin in pregnancy, its function in the human placenta is unclear. In the current study, we aimed to understand key roles of Irisin through its ability to protect against apoptosis is the preeclamptic placenta and in ex vivo and in vitro models of hypoxia/re-oxygenation (H/R) injury. Our studies show that Irisin prevents cell death by reducing pro-apoptotic signaling cascades, reducing cleavage of PARP to induce DNA repair pathways and reducing activity of Caspase 3. Irisin caused an increase in the levels of anti-apoptotic BCL2 to pro-apoptotic BAX and reduced ROS levels in an in vitro model of placental ischemia. Furthermore, we show that Irisin treatment acts through the Akt signaling pathway to prevent apoptosis and enhance cell survival. Our findings provide a novel understanding for the anti-apoptotic and pro-survival properties of Irisin in the human placenta under pathological conditions. This work yields new insights into placental development and disease and points towards intervention strategies for placental insufficiencies, such as PE, by protecting and maintaining placental function through inhibiting hypoxic ischemia-induced apoptosis.

The Role of the Gastric Hormones Ghrelin and Nesfatin-1 in Reproduction

Ghrelin and nesfatin-1 are enteroendocrine peptide hormones expressed in rat X/A-like and human P/D1cells of the gastric mucosa. Besides their effect on food intake, both peptides are also implicated in various other physiological systems. One of these is the reproductive system. This present review illustrates the distribution of ghrelin and nesfatin-1 along the hypothalamus–pituitary–gonadal (HPG) axis, their modulation by reproductive hormones, and effects on reproductive functions as well as highlighting gaps in current knowledge to foster further research.

Efficacy of Low Molecular Heparin on Preeclampsia by Inhibiting Apoptosis of Trophoblasts via the p38MAPK Signaling Pathway

OBJECTIVE

To explore the efficacy of low molecular heparin on preeclampsia by inhibiting apoptosis of trophoblasts via the p38MAPK signaling pathway.

METHODS

A preeclampsia rat model was established, and the effects of low molecular heparin on preeclampsia via the p38MAPK signaling pathway were analyzed based on intervention of the rats with different combinations of low molecular heparin and p38MAPK signaling pathway activator. Furthermore, a hypoxia/reoxygenation model of trophoblasts in vitro was established to explore the effects of low molecular heparin on trophoblasts via the p38MAPK signaling pathway.

RESULTS

After treatment with low molecular heparin, pregnant rats in the heparin group showed significantly decreased blood pressure, 24 h proteinuria, and p38MAPK protein levels in placenta tissues and decreased apoptosis rate of placenta tissue cells (all P < 0.05) and showed more fetal rats and lowered weight of them (both P < 0.05) but showed no significant change in the weight of placenta (all P > 0.05). Pregnant rats treated with low molecular heparin and p38MAPK activator showed significantly higher blood pressure, 24 h proteinuria, and p38MAPK protein levels in placenta tissues and apoptosis rate of placenta tissue cells than those of pregnant rats in the heparin group (all P < 0.05) and also showed less fetal rats and lighter fetal rats than those in the heparin group (both P < 0.05) but showed no difference with them in the weight of placenta (P > 0.05). Further analysis revealed that low molecular heparin could protect the survival and migration of trophoblasts under hypoxia/reoxygenation conditions and reduce apoptosis of them (all P < 0.05).

CONCLUSION

Low molecular heparin can alleviate preeclampsia by inhibiting the p38MAPK signaling pathway and can inhibit apoptosis of trophoblasts and promote proliferation and migration of them.

Melatonin, a Potential Therapeutic Agent for Preeclampsia, Reduces the Extrusion of Toxic Extracellular Vesicles from Preeclamptic Placentae

Preeclampsia, characterised by maternal endothelial cell activation, is triggered by toxic factors, such as placental extracellular vesicles (EVs) from a dysfunctional placenta. The increased oxidative stress seen in the preeclamptic placenta links to endoplasmic reticulum (ER) stress. The ER regulates protein folding and trafficking. When the ER is stressed, proteins are misfolded, and misfolded proteins are toxic. Misfolded proteins can be exported from cells, via EVs which target to other cells where the misfolded proteins may also be toxic. Melatonin is a hormone and antioxidant produced by the pineal gland and placenta. Levels of melatonin are reduced in preeclampsia. In this study we investigated whether melatonin treatment can change the nature of placental EVs that are released from a preeclamptic placenta. EVs were collected from preeclamptic (n = 6) and normotensive (n = 6) placental explants cultured in the presence or absence of melatonin for 18 h. Misfolded proteins were measured using a fluorescent compound, Thioflavin-T (ThT). Endothelial cells were exposed to placental EVs overnight. Endothelial cell activation was measured by the quantification of cell-surface ICAM-1 using a cell-based ELISA. EVs from preeclamptic placentae carried significantly (p < 0.001) more misfolded proteins than normotensive controls. Incubating preeclamptic placental explants in the presence of melatonin (1 µM and 10 µM) significantly (p < 0.001) reduced the misfolded proteins carried by EVs. Culturing endothelial cells in the presence of preeclamptic EVs significantly increased the expression of ICAM-1. This increased ICAM-1 expression was significantly reduced when the endothelial cells were exposed to preeclamptic EVs cultured in the presence of melatonin. This study demonstrates that melatonin reduces the amount of misfolded proteins carried by EVs from preeclamptic placentae and reduces the ability of these EVs to activate endothelial cells. Our study provides further preclinical support for the use of melatonin as a treatment for preeclampsia.

Long-chain polyunsaturated fatty acid (LC-PUFA) status in severe preeclampsia and preterm birth: a cross sectional study

Long-Chain Polyunsaturated Fatty Acid (LCPUFA) is essential throughout pregnancy, since deficiency of LPUFA may linked to obstetrical complications. This study aimed to investigate LCPUFA status in severe preeclampsia and preterm birth. A cross sectional study was conducted in 104 pregnant women, which divided into normal pregnancy, severe preeclampsia and preterm birth groups. Serum percentage and concentration of total LCPUFA, omega-3, alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), omega-6, linoleic acid (LA), and arachidonic acid (AA) were measured using gas chromatography/mass spectrometry. Receiver operating characteristic (ROC), bivariate and multivariate analysis were performed. Severe preeclampsia showed the highest concentration of total PUFA and the lowest DHA percentage, with significantly higher Omega-6/Omega-3 ratio (p = 0.004) and lower omega-3 index (p < 0.002) compared to control. Preterm birth showed the least omega-3 concentrations, with significantly low omega-6 derivates (LA (p = 0.014) and AA (p = 0.025)) compared to control. LCPUFA parameters have shown to increase the risk in both conditions, particularly ALA ≤ 53 µmol/L in preeclampsia with OR 5.44, 95%CI 1.16-25.42 and preterm birth with OR 4.68, 95%CI 1.52-14.38. These findings suggest that severe preeclampsia and preterm birth have an imbalance in LCPUFA status.

Megalin, Proton Pump Inhibitors and the Renin-Angiotensin System in Healthy and Pre-Eclamptic Placentas

Soluble Fms-like tyrosine kinase-1 (sFlt-1) is increased in pre-eclampsia. The proton pump inhibitor (PPI) lowers sFlt-1, while angiotensin increases it. To investigate whether PPIs lower sFlt-1 by suppressing placental renin–angiotensin system (RAS) activity, we studied gene expression and protein abundance of RAS components, including megalin, a novel endocytic receptor for prorenin and renin, in placental tissue obtained from healthy pregnant women and women with early-onset pre-eclampsia. Renin, ACE, ACE2, and the angiotensin receptors were expressed at identical levels in healthy and pre-eclamptic placentas, while both the (pro)renin receptor and megalin were increased in the latter. Placental prorenin levels were upregulated in pre-eclamptic pregnancies. Angiotensinogen protein, but not mRNA, was detectable in placental tissue, implying that it originates from maternal blood. Ex vivo placental perfusion revealed a complete washout of angiotensinogen, while prorenin release remained constant. The PPI esomeprazole dose-dependently reduced megalin/(pro)renin receptor-mediated renin uptake in Brown Norway yolk sac epithelial cells and decreased sFlt-1 secretion from placental villous explants. Megalin inhibition blocked angiotensinogen uptake in epithelial cells. In conclusion, our data suggest that placental RAS activity depends on angiotensinogen taken up from the maternal systemic circulation. PPIs might interfere with placental (pro)renin-AGT uptake/transport, thereby reducing angiotensin formation as well as angiotensin-induced sFlt-1 synthesis.

YB-1 Is Altered in Pregnancy-Associated Disorders and Affects Trophoblast in Vitro Properties via Alternation of Multiple Molecular Traits

Cold shock Y-box binding protein-1 (YB-1) coordinates several molecular processes between the nucleus and the cytoplasm and plays a crucial role in cell function. Moreover, it is involved in cancer progression, invasion, and metastasis. As trophoblast cells share similar characteristics with cancer cells, we hypothesized that YB-1 might also be necessary for trophoblast functionality. In samples of patients with intrauterine growth restriction, YB-1 mRNA levels were decreased, while they were increased in preeclampsia and unchanged in spontaneous abortions when compared to normal pregnant controls. Studies with overexpression and downregulation of YB-1 were performed to assess the key trophoblast processes in two trophoblast cell lines HTR8/SVneo and JEG3. Overexpression of YB-1 or exposure of trophoblast cells to recombinant YB-1 caused enhanced proliferation, while knockdown of YB-1 lead to proliferative disadvantage in JEG3 or HTR8/SVneo cells. The invasion and migration properties were affected at different degrees among the trophoblast cell lines. Trophoblast expression of genes mediating migration, invasion, apoptosis, and inflammation was altered upon YB-1 downregulation. Moreover, IL-6 secretion was excessively increased in HTR8/SVneo. Ultimately, YB-1 directly binds to NF-κB enhancer mark in HTR8/SVneo cells. Our data show that YB-1 protein is important for trophoblast cell functioning and, when downregulated, leads to trophoblast disadvantage that at least in part is mediated by NF-κB.

GestAltNet: aggregation and attention to improve deep learning of gestational age from placental whole-slide images

The placenta is the first organ to form and performs the functions of the lung, gut, kidney, and endocrine systems. Abnormalities in the placenta cause or reflect most abnormalities in gestation and can have life-long consequences for the mother and infant. Placental villi undergo a complex but reproducible sequence of maturation across the third-trimester. Abnormalities of villous maturation are a feature of gestational diabetes and preeclampsia, among others, but there is significant interobserver variability in their diagnosis. Machine learning has emerged as a powerful tool for research in pathology. To capture the volume of data and manage heterogeneity within the placenta, we developed GestaltNet, which emulates human attention to high-yield areas and aggregation across regions. We used this network to estimate the gestational age (GA) of scanned placental slides and compared it to a baseline model lacking the attention and aggregation functions. In the test set, GestaltNet showed a higher r2 (0.9444 vs. 0.9220) than the baseline model. The mean absolute error (MAE) between the estimated and actual GA was also better in the GestaltNet (1.0847 weeks vs. 1.4505 weeks). On whole-slide images, we found the attention sub-network discriminates areas of terminal villi from other placental structures. Using this behavior, we estimated GA for 36 whole slides not previously seen by the model. In this task, similar to that faced by human pathologists, the model showed an r2 of 0.8859 with an MAE of 1.3671 weeks. We show that villous maturation is machine-recognizable. Machine-estimated GA could be useful when GA is unknown or to study abnormalities of villous maturation, including those in gestational diabetes or preeclampsia. GestaltNet points toward a future of genuinely whole-slide digital pathology by incorporating human-like behaviors of attention and aggregation.

Bioenergetics adaptations and redox homeostasis in pregnancy and related disorders

Pregnancy is a challenging physiological process that involves maternal adaptations to the increasing energetics demands imposed by the growing conceptus. Failure to adapt to these requirements may result in serious health complications for the mother and the baby. The mitochondria are biosynthetic and energy-producing organelles supporting the augmented energetic demands of pregnancy. Evidence suggests that placental mitochondria display a dynamic phenotype through gestation. At early stages of pregnancy placental mitochondria are mainly responsible for the generation of metabolic intermediates and reactive oxygen species (ROS), while at later stages of gestation, the placental mitochondria exhibit high rates of oxygen consumption. This review describes the metabolic fingerprint of the placental mitochondria at different stages of pregnancy and summarises key signs of mitochondrial dysfunction in pathological pregnancy conditions, including preeclampsia, gestational diabetes and intrauterine growth restriction (IUGR). So far, the effects of placental-driven metabolic changes governing the metabolic adaptations occurring in different maternal tissues in both, healthy and pathological pregnancies, remain to be uncovered. Understanding the function and molecular aspects of the adaptations occurring in placental and maternal tissue's mitochondria will unveil potential targets for further therapeutic exploration that could address pregnancy-related disorders. Targeting mitochondrial metabolism is an emerging approach for regulating mitochondrial bioenergetics. This review will also describe the potential therapeutic use of compounds with a recognised effect on mitochondria, for the management of preeclampsia.

Primary hyperparathyroidism in pregnancy: observations from the Indian PHPT registry

PURPOSE

To present the data on primary hyperparathyroidism (PHPT) in pregnancy from India obtained from a large database maintained over 15 years.

METHODS

We retrieved data of all women with gestational PHPT from the Indian PHPT registry between July 2005 and January 2020, and compared their clinical, biochemical, and other characteristics with age-matched non-pregnant women with PHPT.

RESULTS

Out of 386 women, eight had gestational PHPT (2.1%). The common presenting manifestations were acute pancreatitis (50%) and renal stone disease (50%); two were asymptomatic. Five women (62.5%) had a history of prior miscarriages. Seven patients (88%) had preeclampsia during the present gestation. Serum calcium and intact parathyroid hormone (iPTH) were not statistically different from the age-matched non-pregnant PHPT group. Six patients with mild-to-moderate hypercalcemia were medically managed with hydration with/without cinacalcet while one patient underwent percutaneous ethanol ablation of the parathyroid adenoma; none underwent surgery during pregnancy. Mean serum calcium maintained from treatment initiation till delivery was 10.5 ± 0.4 mg/dl. One patient had spontaneous preterm delivery at 36 weeks; the remaining patients had normal vaginal delivery at term. None had severe preeclampsia/eclampsia. Fetal outcomes included low birth weight in three newborns (37.5%); two of them had hypocalcemic seizures.

CONCLUSION

The prevalence of gestational PHPT was 2.1% in this largest Indian PHPT cohort, which is higher than that reported from the West (< 1%). Gestational PHPT can lead to preeclampsia and miscarriage. Pregnant PHPT patients with mild-to-moderate hypercalcemia can be managed with hydration/cinacalcet; however, long-term safety data and large-scale randomized controlled trials are required.

Mapping themes trends and knowledge structure of trophoblastic invasion, a bibliometric analysis from 2012-2021

OBJECTIVES

Trophoblastic invasion at the maternal-fetal interface can affect pregnancy outcomes. To describe an intuitive theme trends and knowledge structure of trophoblastic invasion-related literature from a bibliometric perspective, and provide researchers with new research hotspots.

STUDY DESIGN

The literature form PubMed database related to trophoblastic invasion from January 1, 2012 to April 30, 2021 were extracted, and then biclustering analysis, co-word analysis, strategy diagram and social network analysis were performed to provide immature, or newly emerging research hotspots for researchers.

RESULTS

A total of 96 high-frequency medical subjects heading terms were extracted and classified into 6 clusters. Themes in the first and second quadrant of strategy diagram, including trophoblasts metabolism, placenta metabolism, pre-eclampsia, etc., as the mature parts of the research on trophoblastic invasion have been well developed. On the other hand, themes in the third and fourth quadrants of strategy diagram, such as embryo implantation and trophoblasts immunology, pregnancy complication, matrix metalloproteinase and trophoblasts metabolism, habitual abortion and trophoblasts metabolism, etc., are immature themes. Social network analysis suggests that themes at the edge, such as habitual abortion / metabolism, placenta / immunology, natural killer cells / physiology, natural killer cells / immunology, embryo implantation / immunology, are considered new research hotspots and have considerable research space.

CONCLUSION

By analyzing the research hotspots related to trophoblastic invasion, immature themes and emerging hotspots deserve more attention and can be considered as hints when launching new research projects.

LncRNA SNHG16 regulates trophoblast functions by the miR-218-5p/LASP1 axis

Altered placental development and function lead to placental diseases such as preeclampsia (PE) which is mainly characterized by insufficient trophoblast invasion and abnormally invasive placenta disorders. Long noncoding RNAs (lncRNAs) are widely reported to function as crucial players in the pathogenesis of PE. The present investigation clarified the role of lncRNA small nucleolar RNA host gene 16 (SNHG16) in PE. RT-qPCR was used to measure gene expression. The proliferation of trophoblast cells was examined using CCK-8 and EdU assays. Trophoblast migration and invasion were assessed using wound healing and transwell assays. The apoptosis was estimated by flow cytometry. Luciferase reporter and RNA pull-down assays were performed to explore the molecular mechanisms in trophoblast cells. We found that SNHG16 was downregulated in placenta from patients with PE. Moreover, SNHG16 depletion significantly inhibited trophoblast cell proliferation, migration, and invasion and stimulated apoptosis, while SNHG16 overexpression exerted an opposite effect. Subsequently, we confirmed that SNHG16 acted as a competing RNA (ceRNA) of miR-218-5p that was verified to directly target LASP1. Both miR-218-5p depletion and LASP1 upregulation antagonized the effect of SNHG16 knockdown on HTR-8/SVneo cell functions. In conclusion, SNHG16 facilitates trophoblast cell migration and invasion by the miR-218-5p/LASP1 axis.

NRP1 and MMP9 are dual targets of RNA-binding protein QKI5 to alter VEGF-R/ NRP1 signalling in trophoblasts in preeclampsia

Preeclampsia (PE) is characterized by placental ischemia and hypoxia, resulting in abnormal casting of the uterine spiral artery, which is mainly caused by insufficient trophoblastic cell infiltration. A reduction in levels of growth factor-based signalling via Neuropilin-1 (NRP1) has been shown to contribute to dysfunctional trophoblast development. In this study, we showed that the RNA-binding protein, QKI5, regulated NRP1 expression and significantly improved trophoblast proliferation in vitro and in vivo. QKI5 and NRP1 expressions were significantly reduced in human PE placentas and in trophoblasts during hypoxia. Overexpression of these factors significantly improved cell proliferation and migration in vitro, in contrast to a decrease upon siRNA knockdown of QKI5 and NRP1 in HTR-8/SVneo cells. Using RIP and RNA pull-down assays, we further showed that QKI5 directly interacted with the 3'-UTR region of NRP1, to mediate cell proliferation and migration via matrix metalloprotease-9. Further, similar to NRP1, QKI5 also targets matrix metalloproteinase 9 (MMP9) involved in secretion of growth factors and its effects can be counteracted by NRP1 overexpression. In vivo studies using a PE mouse model revealed that QKI5 overexpression alleviated PE-related symptoms such as elevated blood pressure and proteinuria. Taken together, we found that QKI5 was a novel regulator, of VEGF-R/NRP1 signalling pathway functioning in trophoblast proliferation and migration, resulting in major contributors to the pathogenesis of PE. While careful evaluation of the broad implications of QKI5 expression is still necessary, this study identified QKI5 as a promising target for treatment strategies in acute PE patients.

Prorenin periconceptionally and in pregnancy: Does it have a physiological role?

Pregnancy demands major cardiovascular, renal and endocrine changes to provide an adequate blood supply for the growing fetus. The renin-angiotensin-aldosterone system plays a key role in this adaptation process. One of its components, prorenin, is released in significant amounts from the ovary and uteroplacental unit. This review describes the sources of prorenin in the periconception period and in pregnancy, including its modulation by in-vitro fertilization protocols, and discusses its potential effects, among others focusing on preeclampsia. It ends with discussing the long-term consequences, even in later life, of inappropriate renin-angiotensin-aldosterone system activity in pregnancy and offers directions for future research. Ultimately, a full understanding of the role of prorenin periconceptionally and during pregnancy will help to develop tools to diagnose and/or prevent reproductive complications.

HMGA1 Is a Potential Driver of Preeclampsia Pathogenesis by Interference with Extravillous Trophoblasts Invasion

Preeclampsia (PE) is a serious disease that can be fatal for the mother and fetus. The two-stage theory has been proposed as its cause, with the first stage comprising poor placentation associated with the failure of fertilized egg implantation. Successful implantation and placentation require maternal immunotolerance of the fertilized egg as a semi-allograft and appropriate extravillous trophoblast (EVT) invasion of the decidua and myometrium. The disturbance of EVT invasion during implantation in PE results in impaired spiral artery remodeling. PE is thought to be caused by hypoxia during remodeling failure-derived poor placentation, which results in chronic inflammation. High-mobility group protein A (HMGA) is involved in the growth and invasion of cancer cells and likely in the growth and invasion of trophoblasts. Its mechanism of action is associated with immunotolerance. Thus, HMGA is thought to play a pivotal role in successful pregnancy, and its dysfunction may be related to the pathogenesis of PE. The evaluation of HMGA function and its changes in PE might confirm that it is a reliable biomarker of PE and provide prospects for PE treatment through the induction of EVT proliferation and invasion during the implantation.

Relationship between proteinuria and optical coherence tomographic features of the chorioretina in patients with pre-eclampsia

This retrospective study aimed to evaluate the correlation between ophthalmologic factors and proteinuria in patients with pre-eclampsia using swept-source optical coherence tomography (OCT) and OCT angiography. In total, 61 pregnant patients diagnosed with pre-eclampsia were recruited during their hospital stay. The authors investigated the relationship between urine protein–creatinine ratio (PCR) and chorioretinal measurements including choroidal thickness (CT), choroidal vascularity index (CVI), foveal avascular zone (FAZ), vascular density (VD), ganglion cell layer+ (GCL+) and GCL++. The associations between mean arterial pressure (MAP) and ophthalmologic factors were also evaluated. Central subfield CT of the right eye (p = 0.031) and paracentral CT of both eyes were related to higher PCR (≥1.35 mg/mg). A significant association with PCR after logarithm transformation was noted (r = 0.284, p = 0.026). Retinal measurements (FAZ, VD, GCL+ and GCL++) and CVI were not related with PCR. There was a positive association between MAP and PCR after logarithm transformation (r = 0.296, p = 0.021); however, chorioretinal factors were not related with MAP. In pregnant women with pre-eclampsia, CT using OCT is a novel factor that is correlated with PCR. Ocular structural alteration in patients with pre-eclampsia may be one of systemic vascular changes caused by pre-eclampsia rather than hypertension.

Angiogenic Properties of Placenta-Derived Extracellular Vesicles in Normal Pregnancy and in Preeclampsia

Angiogenesis is one of the main processes that coordinate the biological events leading to a successful pregnancy, and its imbalance characterizes several pregnancy-related diseases, including preeclampsia. Intracellular interactions via extracellular vesicles (EVs) contribute to pregnancy's physiology and pathophysiology, and to the fetal-maternal interaction. The present review outlines the implications of EV-mediated crosstalk in the angiogenic process in healthy pregnancy and its dysregulation in preeclampsia. In particular, the effect of EVs derived from gestational tissues in pro and anti-angiogenic processes in the physiological and pathological setting is described. Moreover, the application of EVs from placental stem cells in the clinical setting is reported.

Implications for preeclampsia: hypoxia-induced Notch promotes trophoblast migration

In the first trimester of human pregnancy, low oxygen tension or hypoxia is essential for proper placentation and placenta function. Low oxygen levels and activation of signaling pathways have been implicated as critical mediators in the promotion of trophoblast differentiation, migration, and invasion with inappropriate changes in oxygen tension and aberrant Notch signaling both individually reported as causative to abnormal placentation. Despite crosstalk between hypoxia and Notch signaling in multiple cell types, the relationship between hypoxia and Notch in first trimester trophoblast function is not understood. To determine how a low oxygen environment impacts Notch signaling and cellular motility, we utilized the human first trimester trophoblast cell line, HTR-8/SVneo. Gene set enrichment and ontology analyses identified pathways involved in angiogenesis, Notch and cellular migration as upregulated in HTR-8/SVneo cells exposed to hypoxic conditions. DAPT, a γ-secretase inhibitor that inhibits Notch activation, was used to interrogate the crosstalk between Notch and hypoxia pathways in HTR-8/SVneo cells. We found that hypoxia requires Notch activation to mediate HTR-8/SVneo cell migration, but not invasion. To determine if our in vitro findings were associated with preeclampsia, we analyzed the second trimester chorionic villous sampling (CVS) samples and third trimester placentas. We found a significant decrease in expression of migration and invasion genes in CVS from preeclamptic pregnancies and significantly lower levels of JAG1 in placentas from pregnancies with early-onset preeclampsia with severe features. Our data support a role for Notch in mediating hypoxia-induced trophoblast migration, which may contribute to preeclampsia development.

The RNA landscape of the human placenta in health and disease

The placenta is the interface between mother and fetus and inadequate function contributes to short and long-term ill-health. The placenta is absent from most large-scale RNA-Seq datasets. We therefore analyze long and small RNAs (~101 and 20 million reads per sample respectively) from 302 human placentas, including 94 cases of preeclampsia (PE) and 56 cases of fetal growth restriction (FGR). The placental transcriptome has the seventh lowest complexity of 50 human tissues: 271 genes account for 50% of all reads. We identify multiple circular RNAs and validate 6 of these by Sanger sequencing across the back-splice junction. Using large-scale mass spectrometry datasets, we find strong evidence of peptides produced by translation of two circular RNAs. We also identify novel piRNAs which are clustered on Chr1 and Chr14. PE and FGR are associated with multiple and overlapping differences in mRNA, lincRNA and circRNA but fewer consistent differences in small RNAs. Of the three protein coding genes differentially expressed in both PE and FGR, one encodes a secreted protein FSTL3 (follistatin-like 3). Elevated serum levels of FSTL3 in pregnant women are predictive of subsequent PE and FGR. To aid visualization of our placenta transcriptome data, we develop a web application ( https://www.obgyn.cam.ac.uk/placentome/ ).

Alternative splicing in normal and pathological human placentas is correlated to genetic variants

Two major obstetric diseases, preeclampsia (PE), a pregnancy-induced endothelial dysfunction leading to hypertension and proteinuria, and intra-uterine growth-restriction (IUGR), a failure of the fetus to acquire its normal growth, are generally triggered by placental dysfunction. Many studies have evaluated gene expression deregulations in these diseases, but none has tackled systematically the role of alternative splicing. In the present study, we show that alternative splicing is an essential feature of placental diseases, affecting 1060 and 1409 genes in PE vs controls and IUGR vs controls, respectively, many of those involved in placental function. While in IUGR placentas, alternative splicing affects genes specifically related to pregnancy, in preeclamptic placentas, it impacts a mix of genes related to pregnancy and brain diseases. Also, alternative splicing variations can be detected at the individual level as sharp splicing differences between different placentas. We correlate these variations with genetic variants to define splicing Quantitative Trait Loci (sQTL) in the subset of the 48 genes the most strongly alternatively spliced in placental diseases. We show that alternative splicing is at least partly piloted by genetic variants located either in cis (52 QTL identified) or in trans (52 QTL identified). In particular, we found four chromosomal regions that impact the splicing of genes in the placenta. The present work provides a new vision of placental gene expression regulation that warrants further studies.

PROVE-Pre-Eclampsia Obstetric Adverse Events: Establishment of a Biobank and Database for Pre-Eclampsia

Pre-eclampsia is a leading cause of maternal and perinatal morbidity and mortality. The burden of disease lies mainly in low-middle income countries. The aim of this project is to establish a pre-eclampsia biobank in South Africa to facilitate research in the field of pre-eclampsia with a focus on phenotyping severe disease.The approach of our biobank is to collect biological specimens, detailed clinical data, tests, and biophysical examinations, including magnetic resonance imaging (MRI) of the brain, MRI of the heart, transcranial Doppler, echocardiography, and cognitive function tests.Women diagnosed with pre-eclampsia and normotensive controls are enrolled in the biobank at admission to Tygerberg University Hospital (Cape Town, South Africa). Biological samples and clinical data are collected at inclusion/delivery and during the hospital stay. Special investigations as per above are performed in a subset of women. After two months, women are followed up by telephonic interviews. This project aims to establish a biobank and database for severe organ complications of pre-eclampsia in a low-middle income country where the incidence of pre-eclampsia with organ complications is high. The study integrates different methods to investigate pre-eclampsia, focusing on improved understanding of pathophysiology, prediction of organ complications, and potentially future drug evaluation and discovery.

Considerations to Model Heart Disease in Women with Preeclampsia and Cardiovascular Disease

Preeclampsia is a multifactorial cardiovascular disorder diagnosed after 20 weeks of gestation, and is the leading cause of death for both mothers and babies in pregnancy. The pathophysiology remains poorly understood due to the variability and unpredictability of disease manifestation when studied in animal models. After preeclampsia, both mothers and offspring have a higher risk of cardiovascular disease (CVD), including myocardial infarction or heart attack and heart failure (HF). Myocardial infarction is an acute myocardial damage that can be treated through reperfusion; however, this therapeutic approach leads to ischemic/reperfusion injury (IRI), often leading to HF. In this review, we compared the current in vivo, in vitro and ex vivo model systems used to study preeclampsia, IRI and HF. Future studies aiming at evaluating CVD in preeclampsia patients could benefit from novel models that better mimic the complex scenario described in this article.

Kidney Injury Caused by Preeclamptic Pregnancy Recovers Postpartum in a Transgenic Rat Model

Preeclampsia (PE) is characterized by the onset of hypertension (≥140/90 mmHg) and presence of proteinuria (>300 mg/L/24 h urine) or other maternal organ dysfunctions. During human PE, renal injuries have been observed. Some studies suggest that women with PE diagnosis have an increased risk to develop renal diseases later in life. However, in human studies PE as a single cause of this development cannot be investigated. Here, we aimed to investigate the effect of PE on postpartum renal damage in an established transgenic PE rat model. Female rats harboring the human-angiotensinogen gene develop a preeclamptic phenotype after mating with male rats harboring the human-renin gene, but are normotensive before and after pregnancy. During pregnancy PE rats developed mild tubular and glomerular changes assessed by histologic analysis, increased gene expression of renal damage markers such as kidney injury marker 1 and connective-tissue growth factor, and albuminuria compared to female wild-type rats (WT). However, four weeks postpartum, most PE-related renal pathologies were absent, including albuminuria and elevated biomarker expression. Only mild enlargement of the glomerular tuft could be detected. Overall, the glomerular and tubular function were affected during pregnancy in the transgenic PE rat. However, almost all these pathologies observed during PE recovered postpartum.

Placental Glycoredox Dysregulation Associated with Disease Progression in an Animal Model of Superimposed Preeclampsia

Pregnancies carried by women with chronic hypertension are at increased risk of superimposed preeclampsia, but the placental pathways involved in disease progression remain poorly understood. In this study, we used the stroke-prone spontaneously hypertensive rat (SHRSP) model to investigate the placental mechanisms promoting superimposed preeclampsia, with focus on cellular stress and its influence on galectin-glycan circuits. Our analysis revealed that SHRSP placentas are characterized by a sustained activation of the cellular stress response, displaying significantly increased levels of markers of lipid peroxidation (i.e., thiobarbituric acid reactive substances (TBARS)) and protein nitration and defective antioxidant enzyme expression as early as gestation day 14 (which marks disease onset). Further, lectin profiling showed that such redox imbalance was associated with marked alterations of the placental glycocode, including a prominent decrease of core 1 O-glycan expression in trophoblasts and increased decidual levels of sialylation in SHRSP placentas. We also observed significant changes in the expression of galectins 1, 3 and 9 with pregnancy progression, highlighting the important role of the galectin signature as dynamic interpreters of placental microenvironmental challenges. Collectively, our findings uncover a new role for the glycoredox balance in the pathogenesis of superimposed preeclampsia representing a promising target for interventions in hypertensive disorders of pregnancy.

Predictors of singleton preterm birth using multinomial regression models accounting for missing data: A birth registry-based cohort study in northern Tanzania

BACKGROUND

Preterm birth is a significant contributor of under-five and newborn deaths globally. Recent estimates indicated that, Tanzania ranks the tenth country with the highest preterm birth rates in the world, and shares 2.2% of the global proportion of all preterm births. Previous studies applied binary regression models to determine predictors of preterm birth by collapsing gestational age at birth to <37 weeks. For targeted interventions, this study aimed to determine predictors of preterm birth using multinomial regression models accounting for missing data.

METHODS

We carried out a secondary analysis of cohort data from the KCMC zonal referral hospital Medical Birth Registry for 44,117 women who gave birth to singletons between 2000-2015. KCMC is located in the Moshi Municipality, Kilimanjaro region, northern Tanzania. Data analysis was performed using Stata version 15.1. Assuming a nonmonotone pattern of missingness, data were imputed using a fully conditional specification (FCS) technique under the missing at random (MAR) assumption. Multinomial regression models with robust standard errors were used to determine predictors of moderately to late ([32,37) weeks of gestation) and very/extreme (<32 weeks of gestation) preterm birth.

RESULTS

The overall proportion of preterm births among singleton births was 11.7%. The trends of preterm birth were significantly rising between the years 2000-2015 by 22.2% (95%CI 12.2%, 32.1%, p<0.001) for moderately to late preterm and 4.6% (95%CI 2.2%, 7.0%, p = 0.001) for very/extremely preterm birth category. After imputation of missing values, higher odds of moderately to late preterm delivery were among adolescent mothers (OR = 1.23, 95%CI 1.09, 1.39), with primary education level (OR = 1.28, 95%CI 1.18, 1.39), referred for delivery (OR = 1.19, 95%CI 1.09, 1.29), with pre-eclampsia/eclampsia (OR = 1.77, 95%CI 1.54, 2.02), inadequate (<4) antenatal care (ANC) visits (OR = 2.55, 95%CI 2.37, 2.74), PROM (OR = 1.80, 95%CI 1.50, 2.17), abruption placenta (OR = 2.05, 95%CI 1.32, 3.18), placenta previa (OR = 4.35, 95%CI 2.58, 7.33), delivery through CS (OR = 1.16, 95%CI 1.08, 1.25), delivered LBW baby (OR = 8.08, 95%CI 7.46, 8.76), experienced perinatal death (OR = 2.09, 95%CI 1.83, 2.40), and delivered male children (OR = 1.11, 95%CI 1.04, 1.20). Maternal age, education level, abruption placenta, and CS delivery showed no statistically significant association with very/extremely preterm birth. The effect of (<4) ANC visits, placenta previa, LBW, and perinatal death were more pronounced on the very/extremely preterm compared to the moderately to late preterm birth. Notably, extremely higher odds of very/extreme preterm birth were among the LBW babies (OR = 38.34, 95%CI 31.87, 46.11).

CONCLUSIONS

The trends of preterm birth have increased over time in northern Tanzania. Policy decisions should intensify efforts to improve maternal and child care throughout the course of pregnancy and childbirth towards preterm birth prevention. For a positive pregnancy outcome, interventions to increase uptake and quality of ANC services should also be strengthened in Tanzania at all levels of care, where several interventions can easily be delivered to pregnant women, especially those at high-risk of experiencing adverse pregnancy outcomes.

Subfoveal Choroidal Thickness and Associated Changes of Angiogenic Factors in Women with Severe Preeclampsia

OBJECTIVE

Severe preeclampsia complicates roughly 1% of all pregnancies. One defining feature of severe preeclampsia is new onset visual disturbance. The accessibility of the choroid to high-resolution, noninvasive imaging makes it a reasonable target of investigation for disease prediction, stratification, or monitoring in preeclampsia. This study aimed to compare subfoveal choroidal thickness between women with severe preeclampsia and those with normotensive pregnancies, and to investigate associations between such findings and other indicators of disease severity, including gestational age and serum angiogenic factors.

STUDY DESIGN

We designed a case-control study comprised of 36 women diagnosed with severe preeclampsia (cases) matched to 37 normotensive women (controls) by race/ethnicity and parity, all diagnosed in the postpartum period. All patients underwent enhanced depth imaging spectral-domain optical coherence tomography and serum analysis.

RESULTS

Cases showed no difference in subfoveal choroidal thickness compared with controls (p = 0.65). Amongst cases, subfoveal choroidal thickness and gestational age at delivery were inversely related (r = 0.86, p < .001). There was a positive association of placental growth factor with subfoveal choroidal thickness amongst cases (r = 0.54, p = 0.002).

CONCLUSION

This study suggests a relationship between the degree of disease severity and the magnitude of choroidal thickening. We also show an association between this index and placental growth factor level in the postpartum period.

S-glutathionylation of the Na+-K+ Pump: A Novel Redox Mechanism in Preeclampsia

CONTEXT

Reduced Na+-K+ pump activity is widely reported in preeclampsia and may be caused by a reversible oxidative modification that is a novel pathological feature of preeclampsia.

OBJECTIVE

This work aims to determine whether β 1 subunit (GSS-β 1) protein glutathionylation of the Na+-K + pump occurs in preeclampsia.

METHODS

The GSS-β1 of the Na+-K+ pump and its subunit expression in human placentas were compared between women with healthy pregnancies and women with preeclampsia. Human placental samples of pregnant women with preeclampsia (n = 11, mean gestational age 36.5 weeks) were used to examine the GSS-β 1 of the Na+-K+ pump, compared to healthy pregnancies (n = 11, mean gestational age 39 weeks).The potential pathogenetic role of GSS-β 1-mediated Na+-K+ pump dysfunction in preeclampsia was investigated.

RESULTS

Protein expression of the β 1 subunit was unchanged in placentas from women with preeclampsia vs those with normotensive pregnancies. Preeclamptic placentas had a significantly increased GSS-β 1 of the Na+-K+ pump compared to those from healthy pregnancies, and this was linked to a decrease in α 1/β 1 subunit coimmunoprecipitation. The cytosolic p47phox nicotinamide adenine dinucleotide phosphate hydrogen (NADPH) oxidase subunit and its coimmunoprecipitation with the α 1 Na+-K+ pump subunit was increased in preeclamptic placentas, thus implicating NADPH oxidase-dependent pump inhibition.

CONCLUSIONS

The high level of β 1 pump subunit glutathionylation provides new insights into the mechanism of Na+-K+ pump dysfunction in preeclampsia.

Pregnancy outcomes in women with vitiligo: A Taiwanese nationwide cohort study

Vitiligo is perceived as an autoimmune skin disease. Previous studies showed conflicting data about vitiligo and pregnancy outcomes. To delineate the associations between vitiligo and the pregnancy outcomes, we used the National Health Insurance Research Database of Taiwan to conduct a retrospective cohort study from January 1, 2000 to December 31, 2015. This study population was composed of 1,096 women with vitiligo and 4,384 women without vitiligo, who were all matched according to age, comorbidity, and index year. Compared with the non-vitiligo controls, women with vitiligo had a higher risk of abortion (aHR 1.158, 95% confidence interval (CI) 1.095–1.258, P < .001). Perinatal events, such as preterm delivery, pre-eclampsia/eclampsia, gestational diabetes mellitus, stillbirth, and intrauterine growth retardation, were not different between both groups (aHR 1.065, 95% CI 0.817–1.157, P = .413). To determine if systemic treatment before conception decreases the risk of abortion, we assessed the medical history of pregnant women with vitiligo 1 year before pregnancy. Patients who were treated with oral medications had a lower risk of abortion than those who were not (aHR: 0.675, 95% CI: 0.482–0.809, P < .001). Our study indicates that there is a higher risk of abortion in pregnant women with vitiligo and the control of disease activity with systemic treatment before conception could improve pregnancy outcomes.

Age and Sex-Related Changes in Human First-Trimester Placenta Transcriptome and Insights into Adaptative Responses to Increased Oxygen

Physiological oxygen tension rises dramatically in the placenta between 8 and 14 weeks of gestation. Abnormalities in this period can lead to gestational diseases, whose underlying mechanisms remain unclear. We explored the changes at mRNA level by comparing the transcriptomes of human placentas at 8–10 gestational weeks and 12–14 gestational weeks. A total of 20 samples were collected and divided equally into four groups based on sex and age. Cytotrophoblasts were isolated and sequenced using RNAseq. Key genes were identified using two different methods: DESeq2 and weighted gene co-expression network analysis (WGCNA). We also constructed a local database of known targets of hypoxia-inducible factor (HIF) subunits, alpha and beta, to investigate expression patterns likely linked with changes in oxygen. Patterns of gene enrichment in and among the four groups were analyzed based on annotations of gene ontology (GO) and KEGG pathways. We characterized the similarities and differences between the enrichment patterns revealed by the two methods and the two conditions (age and sex), as well as those associated with HIF targets. Our results provide a broad perspective of the processes that are active in cytotrophoblasts during the rise in physiological oxygen, which should benefit efforts to discover possible drug-targeted genes or pathways in the human placenta.

Pathophysiology of Preeclampsia: The Role of Exosomes

The pathogenesis of preeclampsia begins when a fertilized egg infiltrates the decidua, resulting in implantation failure (e.g., due to extravillous trophoblast infiltration disturbance and abnormal spiral artery remodeling). Thereafter, large amounts of serum factors (e.g., soluble fms-like tyrosine kinase 1 and soluble endoglin) are released into the blood from the hypoplastic placenta, and preeclampsia characterized by multiorgan disorder caused by vascular disorders develops. Successful implantation and placentation require immune tolerance to the fertilized egg as a semi-allograft and the stimulation of extravillous trophoblast infiltration. Recently, exosomes with diameters of 50-100 nm have been recognized to be involved in cell-cell communication. Exosomes affect cell functions in autocrine and paracrine manners via their encapsulating microRNA/DNA and membrane-bound proteins. The microRNA profiles of blood exosomes have been demonstrated to be useful for the evaluation of preeclampsia pathophysiology and prediction of the disease. In addition, exosomes derived from mesenchymal stem cells have been found to have cancer-suppressing effects. These exosomes may repair the pathophysiology of preeclampsia through the suppression of extravillous trophoblast apoptosis and promotion of these cells' invasive ability. Exosomes secreted by various cells have received much recent attention and may be involved in the maintenance of pregnancy and pathogenesis of preeclampsia.

Astragaloside IV alleviates lipopolysaccharide-induced preeclampsia-like phenotypes via suppressing the inflammatory responses

Preeclampsia (PE) is a major cause of perinatal and maternal mortality and morbidity, which affects 2% to 8% of pregnancies in the world. The aberrant maternal inflammation and angiogenic imbalance have been demonstrated to contribute to the pathogenesis of PE. This research aimed to investigate the effect of Astragaloside IV (AsIV) in the treatment of PE and the underlying mechanisms. A rat PE-like model was established by tail vein injection of lipopolysaccharide (LPS) and different doses of AsIV (40 and 80 mg/kg) were treated at the same time. Systolic blood pressure, total urine protein and urine volume were observed. Serum and placenta inflammatory cytokines were measured by ELISA kit. The mRNA and protein expression of relative genes were analyzed by qRT-PCR and Western blotting. In PE-like rats, there were obvious increases in systolic blood pressure, total urine protein and urine volume, which were obviously alleviated by treatment with AsIV. Serum levels of interleukin (IL)-1β, tumor necrosis factor alpha (TNF-α), IL-6 and IL-18, as well as IL-4, IL-10, PIGF, VEGF and sFlt-1, were all reversed by treatment with AsIV. Meanwhile, AsIV treatment improved abnormal pregnancy outcomes, such as low litter size and low fetal weight. In addition, AsIV treatment downregulated the mRNA expression of inflammatory gene IL-1β and IL-6 in PE rats model, and AsIV treatment inhibited the activation of TLR-4, NF-κB, and sFlt-1 in the placenta of PE rats. Our findings indicated the first evidence that AsIV alleviated PE-like signs, and this improvement effect is possibly through inhibition of inflammation response via the TLR4/NF-κB signaling pathway.

Role of the Macrophage Migration Inhibitory Factor in the Pathophysiology of Pre-Eclampsia

Proinflammatory cytokines are produced in pregnancy in response to the invading pathogens and/or nonmicrobial causes such as damage-associated molecules and embryonic semi-allogenic antigens. While inflammation is essential for a successful pregnancy, an excessive inflammatory response is implicated in several pathologies including pre-eclampsia (PE). This review focuses on the proinflammatory cytokine macrophage migration inhibitory factor (MIF), a critical regulator of the innate immune response and a major player of processes allowing normal placental development. PE is a severe pregnancy-related syndrome characterized by exaggerated inflammatory response and generalized endothelial damage. In some cases, usually of early onset, it originates from a maldevelopment of the placenta, and is associated with intrauterine growth restriction (IUGR) (placental PE). In other cases, usually of late onset, pre-pregnancy maternal diseases represent risk factors for the development of the disease (maternal PE). Available data suggest that low MIF production in early pregnancy could contribute to the abnormal placentation. The resulting placental hypoxia in later pregnancy could produce high release of MIF in maternal serum typical of placental PE. More studies are needed to understand the role of MIF, if any, in maternal PE.

Signs of neuroaxonal injury in preeclampsia-A case control study

BACKGROUND

Cerebral injury is a common cause of maternal mortality due to preeclampsia and is challenging to predict and diagnose. In addition, there are associations between previous preeclampsia and stroke, dementia and epilepsy later in life. The cerebral biomarkers S100B, neuron specific enolase, (NSE), tau protein and neurofilament light chain (NfL) have proven useful as predictors and diagnostic tools in other neurological disorders. This case-control study sought to determine whether cerebral biomarkers were increased in cerebrospinal fluid (CSF) as a marker of cerebral origin and potential cerebral injury in preeclampsia and if concentrations in CSF correlated to concentrations in plasma.

METHODS

CSF and blood at delivery from 15 women with preeclampsia and 15 women with normal pregnancies were analysed for the cerebral biomarkers S100B, NSE, tau protein and NfL by Simoa and ELISA based methods. MRI brain was performed after delivery and for women with preeclampsia also at six months postpartum.

RESULTS

Women with preeclampsia demonstrated increased CSF- and plasma concentrations of NfL and these concentrations correlated to each other. CSF concentrations of NSE and tau were decreased in preeclampsia and there were no differences in plasma concentrations of NSE and tau between groups. For S100B, serum concentrations in preeclampsia were increased but there was no difference in CSF concentrations of S100B between women with preeclampsia and normal pregnancy.

CONCLUSION

NfL emerges as a promising circulating cerebral biomarker in preeclampsia and increased CSF concentrations point to a neuroaxonal injury in preeclampsia, even in the absence of clinically evident neurological complications.

Effect of edaravone on pregnant mice and their developing fetuses subjected to placental ischemia

Growing evidence indicates that reduced uterine perfusion pressure (RUPP) triggers the cascade of events leading to preeclampsia. Edaravone is a powerful free radical scavenger used for the treatment of ischemia/reperfusion diseases due to its anti-oxidative stress and anti-inflammatory properties. Here we investigate the effect of edaravone (3 mg/kg) on different maternal and fetal outcomes of RUPP-induced placental ischemia mice model. RUPP surgery was performed on gestation day (GD) 13 followed by edaravone injection from GD14 to GD18, sacrifice day. The results showed that edaravone injection significantly decreased the maternal blood pressure (113.2 ± 2.3 mmHg) compared with RUPP group (131.5 ± 1.9 mmHg). Edaravone increased fetal survival rate (75.4%) compared with RUPP group (54.4%), increased fetal length, weights, and feto-placental ratio (7.2 and 5.7 for RUPP and RUPP-Edaravone groups, respectively) compared with RUPP group. In addition, RUPP resulted in many fetal morphological abnormalities as well as severe delayed ossification, however edaravone decreased the morphological abnormalities and increased the ossification of the fetal endoskeleton. Edaravone improved the histopathological structure of the maternal kidney and heart as well as decreased the elevated blood urea and creatinine levels (31.5 ± 0.15 mg/dl (RUPP), 25.6 ± 0.1 mg/dl (RUPP+edaravone) for urea and 5.4 ± 0.1 mg/dl (RUPP), 3.5 ± 0.1 mg/dl (RUPP+edaravone) for creatinine) and decreased cleaved caspase-3 expression in the maternal kidney. In conclusion, this study demonstrated that our RUPP mice model recapitulated preeclampsia symptoms and edaravone injection ameliorated most of these abnormalities suggesting its effectiveness and potential application in preeclampsia treatment regimes.

Complement and coagulation cascades activation is the main pathophysiological pathway in early-onset severe preeclampsia revealed by maternal proteomics

Preeclampsia is a pregnancy-specific multisystem disorder and a leading cause of maternal and perinatal morbidity and mortality. The exact pathogenesis of this multifactorial disease remains poorly defined. We applied proteomics analysis on maternal blood samples collected from 14 singleton pregnancies with early-onset severe preeclampsia and 6 uncomplicated pregnancies to investigate the pathophysiological pathways involved in this specific subgroup of preeclampsia. Maternal blood was drawn at diagnosis for cases and at matched gestational age for controls. LC-MS/MS proteomics analysis was conducted, and data were analyzed by multivariate and univariate statistical approaches with the identification of differential pathways by exploring the global human protein-protein interaction network. The unsupervised multivariate analysis (the principal component analysis) showed a clear difference between preeclamptic and uncomplicated pregnancies. The supervised multivariate analysis using orthogonal partial least square discriminant analysis resulted in a model with goodness of fit (R2X = 0.99, p < 0.001) and a strong predictive ability (Q2Y = 0.8, p < 0.001). By univariate analysis, we found 17 proteins statistically different after 5% FDR correction (q-value < 0.05). Pathway enrichment analysis revealed 5 significantly enriched pathways whereby the activation of the complement and coagulation cascades was on top (p = 3.17e-07). To validate these results, we assessed the deposits of C5b-9 complement complex and on endothelial cells that were exposed to activated plasma from an independent set of 4 cases of early-onset severe preeclampsia and 4 uncomplicated pregnancies. C5b-9 and Von Willbrand factor deposits were significantly higher in early-onset severe preeclampsia. Future studies are warranted to investigate potential therapeutic targets for early-onset severe preeclampsia within the complement and coagulation pathway.

Preeclampsia: inflammatory signature of decidual cells in early manifestation of disease

INTRODUCTION

Preeclampsia is a pregnancy-specific complication characterized by hypertension in combination with proteinuria and/or various manifestations of multiple organ failure. It is believed that etiology of preeclampsia lies in dysfunction of the placenta and disorder of the maternal-fetal interactions. In preeclampsia decidual membrane, the maternal part of the placenta which normally supports immunological tolerance of the maternal organism to the semi-allogeneic fetus, becomes a site of inflammation.

METHODS

The aim of our study was to characterize the phenotype of decidual macrophages and plasma profiles in patients with late- and early-onset preeclampsia as compared with controls (n = 43). Decidual cells were obtained by enzymatic digestion method and characterized by flow cytometry analysis, real-time PCR, bioinformatics analysis, immunohistochemistry, and Western blot. Plasma samples were analyzed by multiplex assay.

RESULTS

The number of inflammation-associated CD86+ and CX3CR1+ cells was significantly higher in the early-onset preeclampsia while the portion of CD163+ cells was significantly higher among studied groups. We observed significant increase of endothelin-1 gene expression and a significant decrease in eNOS and GNB3 expression and TGFβ relative protein level in decidual cells of the early-onset preeclampsia samples. We also revealed elevation of pro- and anti-inflammatory cytokines in plasma of preeclampsia groups.

DISCUSSION

Our findings reflect profound early-onset preeclampsia-associated alterations in the decidua and emphasize the importance of the decidua as a link in the development of preeclampsia.

Hypoxia-induced mitochondrial abnormalities in cells of the placenta

INTRODUCTION

Impaired utero-placental perfusion is a well-known feature of early preeclampsia and is associated with placental hypoxia and oxidative stress. Although aberrations at the level of the mitochondrion have been implicated in PE pathophysiology, whether or not hypoxia-induced mitochondrial abnormalities contribute to placental oxidative stress is unknown.

METHODS

We explored whether abnormalities in mitochondrial metabolism contribute to hypoxia-induced placental oxidative stress by using both healthy term placentae as well as a trophoblast cell line (BeWo cells) exposed to hypoxia. Furthermore, we explored the therapeutic potential of the antioxidants MitoQ and quercetin in preventing hypoxia-induced placental oxidative stress.

RESULTS

Both in placental explants as well as BeWo cells, hypoxia resulted in reductions in mitochondrial content, decreased abundance of key molecules involved in the electron transport chain and increased expression and activity of glycolytic enzymes. Furthermore, expression levels of key regulators of mitochondrial biogenesis were decreased while the abundance of constituents of the mitophagy, autophagy and mitochondrial fission machinery was increased in response to hypoxia. In addition, placental hypoxia was associated with increased oxidative stress, inflammation, and apoptosis. Moreover, experiments with MitoQ revealed that hypoxia-induced reactive oxygen species originated from the mitochondria in the trophoblasts.

DISCUSSION

This study is the first to demonstrate that placental hypoxia is associated with mitochondrial-generated reactive oxygen species and significant alterations in the molecular pathways controlling mitochondrial content and function. Furthermore, our data indicate that targeting mitochondrial oxidative stress may have therapeutic benefit in the management of pathologies related to placental hypoxia.

Circulating Total Cell-Free DNA Levels Are Increased in Hypertensive Disorders of Pregnancy and Associated with Prohypertensive Factors and Adverse Clinical Outcomes

Previous studies have described increased circulating cell-free DNA (cfDNA) in hypertensive disorders of pregnancy (HDP). Here, we aimed first to confirm this information using a simple, but sensible fluorescent assay, and second to investigate whether total cfDNA is associated with circulating factors known to be linked to the pathophysiology of HDP as well as with poor maternal-fetal outcomes. We studied 98 women with healthy pregnancies (HP), 88 with gestational hypertension (GH), and 91 with preeclampsia (PE). Total DNA was extracted from plasma using the QIAamp DNA blood mini kit and quantified using Quant-iT™ PicoGreen® dsDNA fluorescent detection kit. We found higher total cfDNA levels in GH and PE (197.0 and 174.2 ng/mL, respectively) than in HP (140.5 ng/mL; both p < 0.0001). Interestingly, total cfDNA levels were elevated in both male and female-bearing pregnancies diagnosed with either HDP, and in more severe versus less severe HDP cases, as classified according to responsiveness to antihypertensive therapy. In addition, total cfDNA was independently associated with HDP, and a cutoff concentration of 160 ng/mL provided appropriate sensitivity and specificity values for diagnosing GH and PE compared to HP (70-85%, both p < 0.0001). Moreover, high total cfDNA was associated with adverse clinical outcomes (high blood pressure, low platelet count, preterm delivery, fetal growth restriction) and high prohypertensive factors (sFLT-1, sEndoglin, MMP-2). These findings represent a step towards to the establishment of cfDNA as a diagnostic tool and the need to understand its role in HDP.

Maternal Serum Angiopoietin-Like 3 Levels in Healthy and Mild Preeclamptic Pregnant Women

OBJECTIVE

Angiopoietin-like protein 3(ANGPTL3) is an important regulator of lipoprotein metabolism in the fed state by inhibiting the enzyme lipoprotein lipase in oxidative tissues. However, the possible role of ANGPTL3 throughout gestation and its relationship with hormonal and biochemical variables are still unknown. The aim of this study was to determinate serum ANGPTL3 level in healthy non-pregnant women, during healthy and preeclamptic pregnancy and postpartum.

METHODS

Serum ANGPTL3 was analyzed by enzyme-linked immunosorbent assay (ELISA), in a prospective cohort of healthy pregnant women (n = 52) and women with mild preeclampsia (n = 21), and women at three months postpartum (n = 20) and healthy non-pregnant women (n = 20). The results obtained were correlated with biochemical, hormonal and anthropometric variables and insulin resistance indices.

RESULTS

Levels of ANGPTL3 were not different between the follicular and the luteal phases of the cycle in healthy non-pregnant women. There was a significant reduction in serum ANGPTL3 levels from the first to the third trimester in healthy pregnant women compared with healthy non-pregnant and postpartum women (p <0.01). ANGPTL3 levels do not differ significantly during the three trimesters of pregnancy neither in healthy women nor in preeclamptic women. The serum levels of ANGPTL3 in women who developed preeclampsia are not statistically different from those observed in healthy pregnant women in each trimester of pregnancy. A significant lineal positive correlation was observed between serum ANGPTL3 levels and triglyceride (P =0.0186, r =0.52), very low-density lipoprotein cholesterol (P =0.0224, r =0.50), and total cholesterol levels (P =0.0220, r =0.50) in healthy non-pregnant women (P 0.05). Besides, there were no significant correlations between serum ANGPTL3 and body mass index (BMI), high-density lipoprotein cholesterol, glucose, insulin, leptin, or HOMA-IR (P >0.05).

CONCLUSIONS

We describe for the first time the profile of ANGPTL3 throughout pregnancy and postpartum as well as and discussed about explore their potential contribution interactions with lipoprotein metabolism throughout pregnancy and postpartum. Thus, low levels of ANGPTL3 during pregnancy might favor lipid uptake in oxidative tissues as the main maternal energy source, while may helping to preserve glucose for use by the fetus and placenta.

Collagen I Induces Preeclampsia-Like Symptoms by Suppressing Proliferation and Invasion of Trophoblasts

Preeclampsia is a common obstetric disorder affecting 2-8% of pregnancy worldwide. Fibrosis is an important histological change occurring in preeclamptic placenta, and might depend on the excess deposition of collagen I. However, the role of fibrotic placenta and collagen I in the pathogenesis of preeclampsia remains unclear. Therefore, we analyzed the collagen deposition and the expression of Collagen I in human placenta by Masson staining, Sirius red staining and western blotting. Further, the role of collagen I in preeclampsia pathogenesis was studied in C57BL/6 mice. HTR-8/SVneo cells were used to investigate the mechanisms underlying the effects of collagen I in trophoblasts by transcriptome sequencing and pharmacological agonists. Human preeclamptic placenta exhibited a significantly higher degree of fibrosis in stem villi and terminal villi than normal placenta, and was characterized by collagen I deposition. In vivo, a single injection of collagen I on gestational day 0.5 led to an increase in systolic pressure of pregnant mice from gestational days 4.5-17.5, to a decrease in weight and number of embryos, and to enhanced placental collagen I expression and degree of fibrosis compared with control mice. In vitro, collagen I attenuated the proliferation and invasion of HTR-8SV/neo cells. This effect could be reversed by treatment with agonists of ERK and β-catenin. Moreover, transcriptome sequencing demonstrated that signaling pathways related to cell proliferation and invasion were significantly downregulated in HTR-8SV/neo cells. Thus, we propose that collagen I induced preeclampsia-like symptoms by suppressing the proliferation and invasion of trophoblasts through inhibition of the ERK phosphorylation and WNT/β-catenin signaling pathways. Our findings could pave the way to the discovery of small-molecule inhibitors for preeclampsia treatment and future studies with larger sample size are required.

Role of Heat Shock Protein 70 (HSP-70) after Giving Nanoherbal Haramonting (Rhodomyrtus tomentosa) in Preeclamptic Rats

BACKGROUND AND OBJECTIVE

Haramonting (Rhodomyrtus tomentosa) is an alternative herb to improve health because it has many biological activities and antioxidant. HSP-70 levels as biomarkers of preeclampsia affected the anti-apoptosis of damaged cells in the placenta. This study aimed to evaluate the role of HSP-70 expressions by investigating whether effect haramonting leaves in PE rats.

MATERIALS AND METHODS

The study design was control (C): pregnant rats without treatment, PE: Preeclamptic rats, PE+E: PE rats were given 1 mL EVOO kg-1 b.wt./day orally (pregnancy 13-19), PE+H: PE rats were given nano herbal haramonting 100 mg kg-1 b.wt. (pregnancy 13-19 days). PE+E+H: PE rats were given EVOO 0.5 mL kg-1 b.wt. and nano herbal haramonting 50 mg kg-1 b.wt. (pregnancy 13-19 day). Surgery was performed by taking blood from the heart for the SGOT/SGPT parameters, creatinine and HSP70.

RESULTS

A significant difference was observed in all groups with the value p<0.0001 and HSP-70 Expressions affect in preeclamptic rats after given this herbal. The value of SGOT, SGPT and creatinine can affect preeclamptic rats and can be as a biomarker of preeclampsia. A significant difference also in fetus weight (p<0.01) but an insignificant difference in placental weight (p>0.05).

CONCLUSION

These findings indicate that Nano herbal haramonting and EVOO possess antioxidative effects and a promising drug for the future in the treatment of preeclampsia.

Placental pathology and maternal factors associated with stillbirth: An institutional based case-control study in Northern Tanzania

OBJECTIVE

To determine the placental pathologies and maternal factors associated with stillbirth at Kilimanjaro Christian Medical Centre, a tertiary referral hospital in Northern Tanzania.

METHODS

A 1:2 unmatched case-control study was carried out among deliveries over an 8-month period. Stillbirths were a case group and live births were the control group. Respective placentas of the newborns from both groups were histopathologically analyzed. Maternal information was collected via chart review. Mean and standard deviation were used to summarize the numerical variables while frequency and percentage were used to summarize categorical variables. Crude and adjusted logistic regressions were done to test the association between each variable and the risk of stillbirth.

RESULTS

A total of 2305 women delivered during the study period. Their mean age was 30 ± 5.9 years. Of all deliveries, 2207 (95.8%) were live births while 98 (4.2%) were stillbirths. Of these, 96 stillbirths (cases) and 192 live births (controls) were enrolled. The average gestational age for the enrolled cases was 33.8 ±3.2 weeks while that of the controls was 36.3±3.6 weeks, (p-value 0.244). Of all stillbirths, nearly two thirds 61(63.5%) were males while the females were 35(36.5%). Of the stillbirth, 41were fresh stillbirths while 55 were macerated. The risk of stillbirth was significantly associated with lower maternal education [aOR (95% CI): 5.22(2.01-13.58)], history of stillbirth [aOR (95%CI): 3.17(1.20-8.36)], lower number of antenatal visits [aOR (95%CI): 6.68(2.71-16.48), pre/eclampsia [aOR (95%CI): 4.06(2.03-8.13)], and ante partum haemorrhage [OR (95%CI): 2.39(1.04-5.53)]. Placental pathology associated with stillbirth included utero-placental vascular pathology and acute chorioamnionitis.

CONCLUSIONS

Educating the mothers on the importance of regular antenatal clinic attendance, monitoring and managing maternal conditions during antenatal periods should be emphasized. Placentas from stillbirths should be histo-pathologically evaluated to better understand the possible aetiology of stillbirths.

Pregnancy-Induced High Plasma Levels of Soluble Endoglin in Mice Lead to Preeclampsia Symptoms and Placental Abnormalities

Preeclampsia is a pregnancy-specific disease of high prevalence characterized by the onset of hypertension, among other maternal or fetal signs. Its etiopathogenesis remains elusive, but it is widely accepted that abnormal placentation results in the release of soluble factors that cause the clinical manifestations of the disease. An increased level of soluble endoglin (sEng) in plasma has been proposed to be an early diagnostic and prognostic biomarker of this disease. A pathogenic function of sEng involving hypertension has also been reported in several animal models with high levels of plasma sEng not directly dependent on pregnancy. The aim of this work was to study the functional effect of high plasma levels of sEng in the pathophysiology of preeclampsia in a model of pregnant mice, in which the levels of sEng in the maternal blood during pregnancy replicate the conditions of human preeclampsia. Our results show that wild type pregnant mice carrying human sEng-expressing transgenic fetuses (fWT(hsEng⁺)) present high plasma levels of sEng with a timing profile similar to that of human preeclampsia. High plasma levels of human sEng (hsEng) are associated with hypertension, proteinuria, fetal growth restriction, and the release of soluble factors to maternal plasma. In addition, fWT(hsEng⁺) mice also present placental alterations comparable to those caused by the poor remodeling of the spiral arteries characteristic of preeclampsia. In vitro and ex vivo experiments, performed in a human trophoblast cell line and human placental explants, show that sEng interferes with trophoblast invasion and the associated pseudovasculogenesis, a process by which cytotrophoblasts switch from an epithelial to an endothelial phenotype, both events being related to remodeling of the spiral arteries. Our findings provide a novel and useful animal model for future research in preeclampsia and reveal a much more relevant role of sEng in preeclampsia than initially proposed.

The Role of the Adipokines in the Most Common Gestational Complications

Adipocytokines are hormonally active molecules that are believed to play a key role in the regulation of crucial biological processes in the human body. Numerous experimental studies established significant alterations in the adipokine secretion patterns throughout pregnancy. The exact etiology of various gestational complications, such as gestational diabetes, preeclampsia, and fetal growth abnormalities, needs to be fully elucidated. The discovery of adipokines raised questions about their potential contribution to the molecular pathophysiology of those diseases. Multiple studies analyzed their local mRNA expression and circulating protein levels. However, most studies report conflicting results. Several adipokines such as leptin, resistin, irisin, apelin, chemerin, and omentin were proposed as potential novel early markers of heterogeneous gestational complications. The inclusion of the adipokines in the standard predictive multifactorial models could improve their prognostic values. Nonetheless, their independent diagnostic value is mostly insufficient to be implemented into standard clinical practice. Routine assessments of adipokine levels during pregnancy are not recommended in the management of both normal and complicated pregnancies. Based on the animal models (e.g., apelin and its receptors in the rodent preeclampsia models), future implementation of adipokines and their receptors as new therapeutic targets appears promising but requires further validation in humans.

Effects of Nanoherbal Haramonting (<i>Rhodomyrtus tomentosa</i>) and Extra Virgin Olive Oil on Histology of Liver and Kidney of Preeclamptic Rats

BACKGROUND AND OBJECTIVE

Preeclampsia (PE) is a life threatening disease prevailing in pregnant women in Indonesia. Impaired kidneys and livers function in PE has a high risk during pregnancy. This study aimed to determine the role of nanoherbal haramonting and Extra Virgin Olive Oil (EVOO) on kidney and liver safety in preeclampsia rats. Nanoherbal Rhodomyrtus tomentosa is a medicinal plant with antioxidant activity such as EVOO which acts as inhibitor of oxidation, reduces lipid peroxidation and increases the speed of epithelialization.

MATERIALS AND METHODS

This study used pregnant rats (Ratus norvegicus) consisting of 5 treatments. Animal models of preeclampsia were made by injection of NaCl 6% 3 mL/day/kg b.wt., subcutaneously in pregnancy of 6-12 days and then given herbs in pregnancy at 13-19 days. The study group consisted of, C-: Normal pregnant rats, C+: PE rats, T1: PE rats were given EVOO, T2: PE rats were given nanoherbal haramonting and T3: PE rats were given EVOO and nanoherbal haramonting. Tissue histology was made by the paraffin method and staining Hematoxylin Eosin which was dissected on the 20th day of pregnancy.

RESULTS

There was no significant difference in weight of the liver and kidneys after administration of EVOO and nanoherbal haramonting. The administration of this herb significantly decreased the narrowing of the kidney tubules and the glomerular diameters. Both of these herbs also repaired preeclamptic liver damage (p<0.05) in normal hepatocyte cells, parenchymal degeneration and necrosis.

CONCLUSION

The EVOO and nanoherbal haramonting repaired preeclamptic liver and kidney damage.

Exploring the role of LC-PUFA metabolism in pregnancy complications

Maternal nutrition during pregnancy plays a significant role in growth and development of the placenta and influencing pregnancy outcome. Suboptimal nutritional status during early gestational period compromises the normal course of pregnancy leading to adverse maternal and fetal outcomes. Omega-3 and omega-6 long chain polyunsaturated fatty acids (LC-PUFA) are important for the growth and development of the placenta. Maternal fatty acids and their metabolites influence the normal course of pregnancy by regulating cell growth and development, cell signaling, regulate angiogenesis, modulate inflammatory responses and influence various structural and functional processes. Alterations in LC-PUFA and their metabolites may result in inadequate spiral artery remodeling or placental angiogenesis leading to structural and functional deficiency of the placenta which contributes to several pregnancy complications like preeclampsia, gestational diabetes mellitus, intrauterine growth restriction, and results in adverse birth outcomes. In this review, we summarize studies examining the role of fatty acids and their metabolites in pregnancy. We also discuss the possible molecular mechanisms through which LC-PUFA influences placental growth and development. Studies have demonstrated that omega-3 fatty acid supplementation lowers the incidence of preterm births, but its effect on reducing pregnancy complications are inconclusive.

The Function of Oncogene B-Cell Lymphoma 6 in the Regulation of the Migration and Invasion of Trophoblastic Cells

Human placentation is a highly invasive process. Deficiency in the invasiveness of trophoblasts is associated with a spectrum of gestational diseases, such as preeclampsia (PE). The oncogene B-cell lymphoma 6 (BCL6) is involved in the migration and invasion of various malignant cells. Intriguingly, its expression is deregulated in preeclamptic placentas. We have reported that BCL6 is required for the proliferation, survival, fusion, and syncytialization of trophoblasts. In the present work, we show that the inhibition of BCL6, either by its gene silencing or by using specific small molecule inhibitors, impairs the migration and invasion of trophoblastic cells, by reducing cell adhesion and compromising the dynamics of the actin cytoskeleton. Moreover, the suppression of BCL6 weakens the signals of the phosphorylated focal adhesion kinase, Akt/protein kinase B, and extracellular regulated kinase 1/2, accompanied by more stationary, but less migratory, cells. Interestingly, transcriptomic analyses reveal that a small interfering RNA-induced reduction of BCL6 decreases the levels of numerous genes, such as p21 activated kinase 1, myosin light chain kinase, and gamma actin related to cell adhesion, actin dynamics, and cell migration. These data suggest BCL6 as a crucial player in the migration and invasion of trophoblasts in the early stages of placental development through the regulation of various genes associated with the migratory machinery.

Upregulation of METTL3 expression and m6A RNA methylation in placental trophoblasts in preeclampsia

INTRODUCTION

N6-methyladenosine (m6A) has been recognized as one of the most abundant and functionally relevant modifications of RNAs and plays critical roles in biological and pathological processes. Placental trophoblast dysfunction significantly contributes to the pathogenesis of preeclampsia. The present study aimed to determine if altered m6A expression occurs in placental trophoblasts in preeclampsia. Expression of m6A methyltransferase (methyltransferase like 3 (METTL3)), m6A demethylases (fat mass and obesity-associated protein (FTO) and AlkB homolog 5 (ALKBH5)), and m6A reader protein, heterogeneous nuclear ribonucleoprotein C1/C2 (hnRNPC1/C2), were also examined.

METHODS

A total of 43 placentas (20 normal term, 5 normotensive preterm, and 18 preeclamptic) were used in the study. Expression of m6A, METTL3, FTO, ALKBH5, and hnRNPC1/C2 were examined by immunostaining in villous tissue sections and/or by Western blot of total cellular protein in trophoblasts isolated from normotensive and preeclamptic placentas. Total RNA extracted from trophoblasts was used to measure m6A RNA methylation. Effects of METTL3 on m6A RNA methylation and hnRNPC1/C2 expression were assessed by transfection of METTL3 siRNA in trophoblasts from preeclamptic placentas.

RESULTS

Expression of m6A and m6A RNA methylation were significantly increased in trophoblasts from preeclamptic vs. normotensive placentas, p < 0.05. Expression of METTL3 and hnRNPC1/C2, but not FTO and ALKBH5, was significantly upregulated in trophoblasts from preeclamptic vs. normotensive placentas, p < 0.01. Transfection of METTL3 siRNA significantly reduced the level of m6A RNA methylation and hnRNPC1/C2 expression in trophoblasts from preeclamptic placentas, p < 0.05.

CONCLUSION

The finding of increased METTL3 expression and m6A RNA methylation associated with increased hnRNPC1/C2 expression provides a new posttranscriptional mechanism that aberrant m6A modification may contribute to trophoblast dysfunction in preeclampsia.