Acute Atherosis Lesions at the Fetal-Maternal Border: Current Knowledge and Implications for Maternal Cardiovascular Health

Identification of immune-related genes and molecular subtypes associated with preeclampsia via bioinformatics analysis and experimental validation

BACKGROUND

Preeclampsia (PE) is a pregnancy disorder that occurs after 20 weeks of pregnancy. The objective of this study was to identify potential immune-related biomarkers and molecular subtypes for the treatment of PE.

METHODS

Three datasets of GSE10588, GSE25906 and GSE48424 were downloaded from the Gene Expression Omnibus (GEO) database. The names of immune-related genes were retrieved from the ImmPort immune database. To screen the differentially expressed immune-related genes, the "limma" R package was used. An analysis of logistic regression was used to identify the key genes and a nomogram was constructed using these key genes. These key gene expression profiles were further validated using qRT-PCR. In addition, the landscape of immune cell infiltration was investigated using the CIBERSORTX software. The potential molecular subtypes of PE were also investigated using the "ConsensusClusterPlus" R package.

RESULTS

The 103 immune-related genes differentially expressed were identified, including 47 up-regulated genes and 56 down-regulated genes. Univariate and multivariate logistic regression analysis was used to screen five key genes, including CCL24, ENG, LCP2, GNAI1 and FLT3. The key genes were strongly associated with immune cell infiltration. Two molecular subtypes (C1 and C2) were identified. Both exhibited distinct levels of immune cell infiltration and gene expression.

CONCLUSION

This study identified five key genes, as well as immune-related subtypes, that could provide potential therapeutic targets and aid in the design of more precise PE immunotherapy.

PlacEntal Acute atherosis RefLecting Subclinical systemic atherosclerosis in women up to 20 years after pre-eclampsia (PEARLS): research protocol for a cohort study

INTRODUCTION

Despite being a leading cause of female morbidity and mortality, female-specific cardiovascular disease (CVD) is understudied, underdiagnosed and undertreated. Pregnancy complications involving the placenta, including pre-eclampsia, pregnancy-induced hypertension and foetal growth restriction, are thought to reflect global maternal vascular derangements that indicate a twofold to eightfold increased risk of future CVD. This calls for a better understanding of female cardiovascular pathophysiology to allow development of targeted screening and prevention strategies.Acute atherosis is a placental vascular lesion, which histologically resembles systemic atherosclerosis. The PlacEntal Acute atherosis RefLecting Subclinical atherosclerosis study investigates the association between placental acute atherosis lesions and subclinical systemic atherosclerosis up to 20 years postpartum.This study will improve our understanding of the relationship between pregnancy complications and CVD to identify potential prevention targets and treatments. In addition, it could determine whether the placenta can improve identification of young women at high risk of CVD. These women could benefit from risk-reducing interventions.

METHODS AND ANALYSIS

This longitudinal prospective cohort study will include women who are either currently pregnant or from a historical cohort. Both groups will have placental histopathology and a single postpartum CVD assessment. The CVD assessment will include medical history taking, blood tests, electrocardiography and echocardiography. Additionally, coronary CT angiography focusing on the presence of atherosclerotic plaques and calcium score will be carried out.The currently pregnant women will either have a pre-eclamptic pregnancy (pre-eclamptic group) or an uncomplicated normotensive pregnancy (uncomplicated group), and their placenta will be collected prospectively. The single CVD assessment will be carried out 6-36 months postpartum.Women from the historical cohort had a pre-eclamptic pregnancy 10-20 years ago. Placental tissue is available for reanalysis. The single CVD assessment will take place immediately and corresponds with 10-20 years postpartum.Exclusion criteria are contraindications to diagnostic assessment necessities: iodinated contrast, beta-blockers or glyceryl trinitrate. Women with uncomplicated pregnancies will be excluded if they have a pre-existing auto-immune condition, chronic hypertension or diabetes mellitus. In the pre-eclamptic group, there are no additional exclusion criteria.

ETHICS AND DISSEMINATION

Ethical approval was granted by the Medical Ethics Committee in Maastricht University Medical Centre+ (NL52556.068.15/METC152019). Participants will give written informed consent. Results will be shared in peer-reviewed journals and conference presentations.

TRIAL REGISTRATION NUMBER

NCT05500989; ClinicalTrials.gov Identifier.

Incorporating placental pathology into clinical care and research

Despite recent standardization of placental evaluation and establishment of criteria for diagnosis of major patterns of placental injury, placental pathological examination remains undervalued and under-utilized. The placenta can harbor a significant amount of information relevant to both the pregnant person and offspring. Placental pathology can also provide a significant context for pathophysiological study of adverse pregnancy outcomes, helping to optimally subcategorize the 'great obstetric syndromes' of pre-eclampsia (PE), spontaneous preterm birth (sPTB), and fetal growth restriction (FGR), and to identify causes of stillbirth. We hereby propose that placental evaluation should be incorporated into routine delivery of obstetric and neonatal care, and further suggest that its integration into clinical, translational, and basic research could significantly advance our understanding of pregnancy complications and adverse neonatal outcomes.

Identification of Preeclamptic Placenta in Whole Slide Images Using Artificial Intelligence Placenta Analysis

BACKGROUND

Preeclampsia (PE) is a hypertensive pregnancy disorder linked to placental dysfunction, often involving pathological lesions like acute atherosis, decidual vasculopathy, accelerated villous maturation, and fibrinoid deposition. However, there is no gold standard for the pathological diagnosis of PE and this limits the ability of clinicians to distinguish between PE and non-PE pregnancies. Recent advances in computational pathology have provided the opportunity to automate pathological analysis for diagnosis, classification, prediction, and prediction of disease progression. In this study, we assessed whether computational pathology could be used to identify PE placentas.

METHODS

A total of 168 placental whole-slide images (WSIs) of patients from Seoul National University Hospital (comprising 84 PE cases and 84 normal controls) were used for model development and internal validation. For external validation of the model, 76 placental slides (including 38 PE cases and 38 normal controls) were obtained from the Boramae Medical Center (BMC). To establish standard criteria for diagnosing PE and distinguishing it from controls using placental WSIs, patch characteristics and quantification of terminal and intermediate villi were employed. In unsupervised learning, K-means clustering was conducted as a feature obtained through an Auto Encoder to extract the ratio of each cluster for each WSI. For supervised learning, quantitative assessments of the villi were obtained using a U-Net-based segmentation algorithm. The prediction model was developed using an ensemble method and was compared with a clinical feature model developed by using placental size features.

RESULTS

Using ensemble modeling, we developed a model to identify PE placentas. The model showed good performance (area under the precision-recall curve [AUPRC], 0.771; 95% confidence interval [CI], 0.752-0.790), with 77.3% of sensitivity and 71.1% of specificity, whereas the clinical feature model showed an AUPRC 0.713 (95% CI, 0.694-0.732) with 55.6% sensitivity and 86.8% specificity. External validation of the predictive model employing the BMC-derived set of placental slides also showed good discrimination (AUPRC, 0.725; 95% CI, 0.720-0.730).

CONCLUSION

The proposed computational pathology model demonstrated a strong ability to identify preeclamptic placentas. Computational pathology has the potential to improve the identification of PE placentas.

Prevalence of placental bed spiral artery pathology in preeclampsia and fetal growth restriction: A prospective cohort study

BACKGROUND

Preeclampsia and fetal growth restriction (PE/FGR) are pregnancy complications known to be associated with poor utero-placental function due to abnormal "physiological" remodeling of spiral arteries and unfavorable maternal cardiovascular health. However, the prevalence and degree of impaired spiral artery remodeling has not been clearly established.

METHOD

Prospective, multi-center observational cohort study to assess the prevalence of lesions associated with abnormal development of spiral arteries in placental bed biopsies systematically obtained from 121 women undergoing Caesarian section for PE/FGR compared with a reference group of 149 healthy controls.

RESULTS

PE/FGR was associated with a high prevalence of impaired spiral artery remodeling compared with controls (63.6 vs 10.1 %, p < 0.001), and a higher prevalence of non-remodeled spiral arteries without the presence of intramural trophoblast (45.5 vs 6.7 %, p < 0.001), despite abundant interstitial trophoblast invasion in surrounding decidua and myometrium. Normal remodeling was associated with circumferential presence of intramural trophoblast and hardly any trophoblast in surrounding tissue. Acute atherosis (28.9 vs 3.4 %, p < 0.001) and thrombosis (16.5 vs 5.4 %, p = 0.003) lesions were significantly more prevalent in PE/FGR. Impaired remodeling, acute atherosis and thrombosis lesions were equally present in both decidual and myometrial segments of the spiral arteries in both groups. Impaired remodeling was most prominent in the groups with FGR (with or without PE) and thrombosis was most often seen in the group with PE and FGR.

CONCLUSION

PE/FGR is associated with a high prevalence of impaired physiological remodeling and vascular lesions of the uterine spiral arteries in the placental bed.

Placental growth factor mediates pathological uterine angiogenesis by activating the NFAT5-SGK1 signaling axis in the endometrium: implications for preeclampsia development

After menstruation the uterine spiral arteries are repaired through angiogenesis. This process is tightly regulated by the paracrine communication between endometrial stromal cells (EnSCs) and endothelial cells. Any molecular aberration in these processes can lead to complications in pregnancy including miscarriage or preeclampsia (PE). Placental growth factor (PlGF) is a known contributing factor for pathological angiogenesis but the mechanisms remain poorly understood. In this study, we investigated whether PlGF contributes to pathological uterine angiogenesis by disrupting EnSCs and endothelial paracrine communication. We observed that PlGF mediates a tonicity-independent activation of nuclear factor of activated T cells 5 (NFAT5) in EnSCs. NFAT5 activated downstream targets including SGK1, HIF-1α and VEGF-A. In depth characterization of PlGF - conditioned medium (CM) from EnSCs using mass spectrometry and ELISA methods revealed low VEGF-A and an abundance of extracellular matrix organization associated proteins. Secreted factors in PlGF-CM impeded normal angiogenic cues in endothelial cells (HUVECs) by downregulating Notch-VEGF signaling. Interestingly, PlGF-CM failed to support human placental (BeWo) cell invasion through HUVEC monolayer. Inhibition of SGK1 in EnSCs improved angiogenic effects in HUVECs and promoted BeWo invasion, revealing SGK1 as a key intermediate player modulating PlGF mediated anti-angiogenic signaling. Taken together, perturbed PlGF-NFAT5-SGK1 signaling in the endometrium can contribute to pathological uterine angiogenesis by negatively regulating EnSCs-endothelial crosstalk resulting in poor quality vessels in the uterine microenvironment. Taken together the signaling may impact on normal trophoblast invasion and thus placentation and, may be associated with an increased risk of complications such as PE.

Behind the Curtain of Abnormal Placentation in Pre-Eclampsia: From Molecular Mechanisms to Histological Hallmarks

Successful human pregnancy needs several highly controlled steps to guarantee an oocyte's fertilization, the embryo's pre-implantation development, and its subsequent implantation into the uterine wall. The subsequent placenta development ensures adequate fetal nutrition and oxygenation, with the trophoblast being the first cell lineage to differentiate during this process. The placenta sustains the growth of the fetus by providing it with oxygen and nutrients and removing waste products. It is not surprising that issues with the early development of the placenta can lead to common pregnancy disorders, such as recurrent miscarriage, fetal growth restriction, pre-eclampsia, and stillbirth. Understanding the normal development of the human placenta is essential for recognizing and contextualizing any pathological aberrations that may occur. The effects of these issues may not become apparent until later in pregnancy, during the mid or advanced stages. This review discusses the process of the embryo implantation phase, the molecular mechanisms involved, and the abnormalities in those mechanisms that are thought to contribute to the development of pre-eclampsia. The review also covers the histological hallmarks of pre-eclampsia as found during the examination of placental tissue from pre-eclampsia patients.

Pregnancy-related maternal physiological adaptations and fetal chemical exposure

Prenatal life represents a susceptible window of development during which chemical exposures can permanently alter fetal development, leading to an increased likelihood of disease later in life. Therefore, it is essential to assess exposure in the fetus. However, direct assessment in human fetuses is challenging, so most research measures maternal exposure. Pregnancy induces a range of significant physiological changes in women that may affect chemical metabolism and responses. Moreover, placental function, fetal sex, and pregnancy complications may further modify these exposures. The purpose of this narrative review is to give an overview of major pregnancy-related physiological changes, including placental function and impacts of pregnancy complications, to summarize existing studies assessing chemical exposure in human fetal organs, and to discuss possible interactions between physiological changes and exposures. Our review reveals major knowledge gaps in factors affecting fetal chemical exposure, highlighting the need to develop more sophisticated tools for chemical health risk assessment in fetuses.

Obliterative foam-cell arteriopathy. A unifying concept embracing several entities previously described as radiation, decidual, transplant, and intratumoral-associated arteriopathy

This review article aimed to postulate the existence of a specific arterial injury having as its histological hallmark a collection of macrophages loaded with lipids in the intima of small-sized and medium-sized arteries causing narrowing or complete obstruction. The proposal is made that a series of previously described entities, such as ionizing radiation arteriopathy, acute atherosis (foam-cell decidual arteriopathy), transplant chronic arteriopathy of solid organ allografts, and intratumoral-associated foam-cell arteriopathy constitute different manifestations of the same basic morphological process identified as obliterative foam-cell arteriopathy (OFCA). OFCA is a local (single-organ) lesion in the aforementioned diverse processes with variable etiopathogenesis but converges in a single morphological marker. This arteriopathy is essentially an intimal disease. The processes in which the OFCA appears are known under a variety of names partly dependent on the location of the lesion. The basic unifying mechanism of the different entities is endothelial activation and dysfunction (local arterial endotheliopathy), preferably in small-sized or medium-sized arteries (100 to 500 μm in external diameter).

Fetal microchimerism and the two-stage model of preeclampsia

Fetal cells cross the placenta during pregnancy and some have the ability to persist in maternal organs and circulation long-term, a phenomenon termed fetal microchimerism. These cells often belong to stem cell or immune cell lineages. The long-term effects of fetal microchimerism are likely mixed, potentially depending on the amount of fetal cells transferred, fetal-maternal histocompatibility and fetal cell-specific properties. Both human and animal data indicate that fetal-origin cells partake in tissue repair and may benefit maternal health overall. On the other hand, these cells have been implicated in inflammatory diseases by studies showing increased fetal microchimerism in women with autoimmune diseases such as systemic lupus erythematosus and rheumatoid arthritis. During pregnancy, preeclampsia is associated with increased cell-transfer between the mother and fetus, and an increase in immune cell subsets. In the current review, we discuss potential mechanisms of transplacental transfer, including passive leakage across the compromised diffusion barrier and active recruitment of cells residing in the placenta or fetal circulation. Within the conceptual framework of the two-stage model of preeclampsia, where syncytiotrophoblast stress is a common pathophysiological pathway to maternal and fetal clinical features of preeclampsia, we argue that microchimerism may represent a mechanistic link between stage 1 placental dysfunction and stage 2 maternal cardiovascular inflammation and endothelial dysfunction. Finally, we postulate that fetal microchimerism may contribute to the known association between placental syndromes and increased long-term maternal cardiovascular disease risk. Fetal microchimerism research represents an exciting opportunity for developing new disease biomarkers and targeted prophylaxis against maternal diseases.

Placental syndromes and maternal cardiovascular health

The placental syndromes gestational hypertension, preeclampsia and intrauterine growth restriction are associated with an increased cardiovascular risk to the mother later in life. In this review, we argue that a woman's pre-conception cardiovascular health drives both the development of placental syndromes and long-term cardiovascular risk but acknowledge that placental syndromes can also contribute to future cardiovascular risk independent of pre-conception health. We describe how preclinical studies in models of preeclampsia inform our understanding of the links with later cardiovascular disease, and how current pre-pregnancy studies may explain relative contributions of both pre-conception factors and the occurrence of placental syndromes to long-term cardiovascular disease.

Maternal and Child Health, Non-Communicable Diseases and Metabolites

Mothers influence the health and disease trajectories of their children, particularly during the critical developmental windows of fetal and neonatal life reflecting the gestational-fetal and lactational-neonatal phases. As children grow and develop, they are exposed to various stimuli and insults, such as metabolites, that shape their physiology and metabolism to impact their health. Non-communicable diseases, such as diabetes, cardiovascular disease, cancer and mental illness, have high global prevalence and are increasing in incidence. Non-communicable diseases often overlap with maternal and child health. The maternal milieu shapes progeny outcomes, and some diseases, such as gestational diabetes and preeclampsia, have gestational origins. Metabolite aberrations occur from diets and physiological changes. Differential metabolite profiles can predict the onset of non-communicable diseases and therefore inform prevention and/or better treatment. In mothers and children, understanding the metabolite influence on health and disease can provide insights for maintaining maternal physiology and sustaining optimal progeny health over the life course. The role and interplay of metabolites on physiological systems and signaling pathways in shaping health and disease present opportunities for biomarker discovery and identifying novel therapeutic agents, particularly in the context of maternal and child health, and non-communicable diseases.

Liver X Receptor Activation Attenuates Oxysterol-Induced Inflammatory Responses in Fetoplacental Endothelial Cells

Oxysterols are oxidized cholesterol derivatives whose systemic levels are found elevated in pregnancy disorders such as gestational diabetes mellitus (GDM). Oxysterols act through various cellular receptors and serve as a key metabolic signal, coordinating inflammation. GDM is a condition of low-grade chronic inflammation accompanied by altered inflammatory profiles in the mother, placenta and fetus. Higher levels of two oxysterols, namely 7-ketocholesterol (7-ketoC) and 7β-hydroxycholesterol (7β-OHC), were observed in fetoplacental endothelial cells (fpEC) and cord blood of GDM offspring. In this study, we tested the effects of 7-ketoC and 7β-OHC on inflammation and investigated the underlying mechanisms involved. Primary fpEC in culture treated with 7-ketoC or 7β-OHC, induced the activation of mitogen-activated protein kinase (MAPK) and nuclear factor kappa B (NFκB) signaling, which resulted in the expression of pro-inflammatory cytokines (IL-6, IL-8) and intercellular cell adhesion molecule-1 (ICAM-1). Liver-X receptor (LXR) activation is known to repress inflammation. Treatment with LXR synthetic agonist T0901317 dampened oxysterol-induced inflammatory responses. Probucol, an inhibitor of LXR target gene ATP-binding cassette transporter A-1 (ABCA-1), antagonized the protective effects of T0901317, suggesting a potential involvement of ABCA-1 in LXR-mediated repression of inflammatory signaling in fpEC. TLR-4 inhibitor Tak-242 attenuated pro-inflammatory signaling induced by oxysterols downstream of the TLR-4 inflammatory signaling cascade. Taken together, our findings suggest that 7-ketoC and 7β-OHC contribute to placental inflammation through the activation of TLR-4. Pharmacologic activation of LXR in fpEC decelerates its shift to a pro-inflammatory phenotype in the presence of oxysterols.

Serum amyloid A1 and pregnancy zone protein in pregnancy complications and correlation with markers of placental dysfunction

BACKGROUND

Hypertensive disorders of pregnancy (preeclampsia, gestational hypertension, and chronic hypertension), diabetes mellitus, and placental dysfunction confer an increased risk of long-term maternal cardiovascular disease. Preeclampsia is also associated with acute atherosis that involves lesions of uteroplacental spiral arteries, resembling early stages of atherosclerosis. Serum amyloid A1 is involved in hypercoagulability and atherosclerosis and may aggregate into amyloid-aggregations of misfolded proteins. Pregnancy zone protein may inhibit amyloid aggregation. Amyloid is involved in Alzheimer's disease and cardiovascular disease; it has been identified in preeclampsia, but its role in preeclampsia pathophysiology is unclear.

OBJECTIVE

We hypothesized that serum amyloid A1 would be increased and pregnancy zone protein decreased in hypertensive disorders of pregnancy and diabetic pregnancies and that serum amyloid A1 and pregnancy zone protein would correlate with placental dysfunction markers (fetal growth restriction and dysregulated angiogenic biomarkers) and acute atherosis.

STUDY DESIGN

Serum amyloid A1 is measurable in both the serum and plasma. In our study, plasma from 549 pregnancies (normotensive, euglycemic controls: 258; early-onset preeclampsia: 71; late-onset preeclampsia: 98; gestational hypertension: 30; chronic hypertension: 9; diabetes mellitus: 83) was assayed for serum amyloid A1 and pregnancy zone protein. The serum levels of angiogenic biomarkers soluble fms-like tyrosine kinase-1 and placental growth factor were available for 547 pregnancies, and the results of acute atherosis evaluation were available for 313 pregnancies. The clinical characteristics and circulating biomarkers were compared between the pregnancy groups using the Mann-Whitney U, chi-squared, or Fisher exact test as appropriate. Spearman's rho was calculated for assessing correlations.

RESULTS

In early-onset preeclampsia, serum amyloid A1 was increased compared with controls (17.1 vs 5.1 µg/mL, P<.001), whereas pregnancy zone protein was decreased (590 vs 892 µg/mL, P=.002). Pregnancy zone protein was also decreased in diabetes compared with controls (683 vs 892 µg/mL, P=.01). Serum amyloid A1 was associated with placental dysfunction (fetal growth restriction, elevated soluble fms-like tyrosine kinase-1 to placental growth factor ratio). Pregnancy zone protein correlated negatively with soluble fms-like tyrosine kinase-1 to placental growth factor ratio in all study groups. Acute atherosis was not associated with serum amyloid A1 or pregnancy zone protein.

CONCLUSION

Proteins involved in atherosclerosis, hypercoagulability, and protein misfolding are dysregulated in early-onset preeclampsia and placental dysfunction, which links them and potentially contributes to future maternal cardiovascular disease.

Preeclampsia and Fetal Growth Restriction as Risk Factors of Future Maternal Cardiovascular Disease-A Review

Cardiovascular diseases (CVDs) remain the leading cause of death in women worldwide. Although traditional risk factors increase later-life CVD, pregnancy-associated complications additionally influence future CVD risk in women. Adverse pregnancy outcomes, including preeclampsia and fetal growth restriction (FGR), are interrelated disorders caused by placental dysfunction, maternal cardiovascular maladaptation to pregnancy, and maternal abnormalities such as endothelial dysfunction, inflammation, hypercoagulability, and vasospasm. The pathophysiologic pathways of some pregnancy complications and CVDs might be linked. This review aimed to highlight the associations between specific adverse pregnancy outcomes and future CVD and emphasize the importance of considering pregnancy history in assessing a woman's CVD risk. Moreover, we wanted to underline the role of maternal cardiovascular maladaptation in the development of specific pregnancy complications such as FGR.

Dissecting the Roles of Lipids in Preeclampsia

Preeclampsia is a multisystem pregnancy disorder that is characterized by different degrees of placental malperfusion, with release of antiangiogenic factors into the circulation, leading to maternal vascular endothelial injury and high blood pressure. As a major cause of maternal and perinatal mortality and morbidity worldwide, once preeclampsia has been diagnosed, there are no curative treatments except for delivery. Lipids serve as ubiquitous and multifunctional metabolites that are integral and essential to many diverse functions on both a cellular and organismal level. Lipid metabolic abnormalities have emerged as potential risk factors for the development and progression of preeclampsia. This review comprehensively examines decades of discovery to illuminate the roles of lipids and dysregulation in the levels of various lipid classes in preeclampsia. In addition, the roles of lipids are summarized to further understand the pathogenic mechanisms of preeclampsia. Overall, the review highlights the promising potential of pathophysiology and lipid-targeting therapeutic strategies in preeclampsia.