Cytokine concentrations direct endothelial function in pregnancy and preeclampsia

Preeclampsia at term: evidence of disease heterogeneity based on the profile of circulating cytokines and angiogenic factors

BACKGROUND

Intravascular inflammation and an antiangiogenic state have been implicated in the pathophysiology of preeclampsia. On the basis of the profiles of their angiogenic/antiangiogenic factors, women with preeclampsia at term may be classified into 2 subgroups with different characteristics and prevalence of adverse outcomes. This study was undertaken to examine whether these 2 subgroups of preeclampsia at term also show differences in their profiles of intravascular inflammation.

OBJECTIVE

This study aimed to determine the plasma profiles of cytokines and chemokines in women with preeclampsia at term who had a normal or an abnormal angiogenic profile.

STUDY DESIGN

A nested case-control study was conducted to include women classified into 3 groups: women with an uncomplicated pregnancy (n=213) and women with preeclampsia at term with a normal (n=55) or an abnormal (n=41) angiogenic profile. An abnormal angiogenic profile was defined as a plasma ratio of placental growth factor and soluble fms-like tyrosine kinase-1 multiple of the median <10th percentile for gestational age. Concentrations of cytokines were measured by multiplex immunoassays.

RESULTS

Women with preeclampsia at term and an abnormal angiogenic profile showed evidence of the greatest intravascular inflammation among the study groups. These women had higher plasma concentrations of 5 cytokines (interleukin-6, interleukin-8, interleukin-12/interleukin-23p40, interleukin-15, and interleukin-16) and 7 chemokines (eotaxin, eotaxin-3, interferon-γ inducible protein-10, monocyte chemotactic protein-4, macrophage inflammatory protein-1β, macrophage-derived chemokine, and thymus and activation-regulated chemokine compared to women with an uncomplicated pregnancy. By contrast, women with preeclampsia at term and a normal angiogenic profile, compared to women with an uncomplicated pregnancy, had only a higher plasma concentration of monocyte chemotactic protein-4. A correlation between severity of the antiangiogenic state, blood pressure, and plasma concentrations of a subset of cytokines was observed.

CONCLUSION

Term preeclampsia can be classified into 2 clusters. One is characterized by an antiangiogenic state coupled with an excessive inflammatory process, whereas the other has neither of these features. These findings further support the heterogeneity of preeclampsia at term and may explain the distinct clinical outcomes.

Immune cells and inflammatory mediators cause endothelial dysfunction in a vascular microphysiological system

Functional assessment of endothelium serves as an important indicator of vascular health and is compromised in vascular disorders including hypertension, atherosclerosis, and preeclampsia. Endothelial dysfunction in these cases is linked to dysregulation of the immune system involving both changes to immune cells and increased secretion of inflammatory cytokines. Herein, we utilize a well-established microfluidic device to generate a 3-dimensional vascular microphysiological system (MPS) consisting of a tubular blood vessel lined with human umbilical vein endothelial cells (HUVECs) to evaluate endothelial function measured via endothelial permeability and Ca2+ signaling. We evaluated the effect of a mixture of factors associated with inflammation and cardiovascular disease (TNFα, VEGF-A, IL-6 at 10 ng ml-1 each) on vascular MPS and inferred that inflammatory mediators contribute to endothelial dysfunction by disrupting the endothelial barrier over a 48 hour treatment and by diminishing coordinated Ca2+ activity over a 1 hour treatment. We also evaluated the effect of peripheral blood mononuclear cells (PBMCs) on endothelial permeability and Ca2+ signaling in the HUVEC MPS. HUVECs were co-cultured with PBMCs either directly wherein PBMCs passed through the lumen or indirectly with PBMCs embedded in the supporting collagen hydrogel. We revealed that phytohemagglutinin (PHA)-M activated PBMCs cause endothelial dysfunction in MPS both through increased permeability and decreased coordinated Ca2+ activity compared to non-activated PBMCs. Our MPS has potential applications in modeling cardiovascular disorders and screening for potential treatments using measures of endothelial function.

Src kinase partially mediates cytokine-induced endothelial dysfunction

OBJECTIVES

Endothelial dysfunction is known to be a key characteristic of preeclampsia (PE) and can contribute to progression of symptoms and injury to multiple organ systems. Delivery is the only treatment for progression of PE, but development of an endothelial-based therapy for PE presents a promising strategy. Growth factors and cytokines are dysregulated in PE and can impact endothelial function, manifesting changes in Ca2+ signaling and interruptions in monolayer barrier function that contribute to symptoms of hypertension, proteinuria, and edema. In this study, we highlight Src kinase as a partial mediator of growth factor and cytokine mediated endothelial dysfunction.

STUDY DESIGN

Fura-2 Ca2+ imaging and Electrical Cell Impedance Sensing (ECIS) assays are performed on growth factor or cytokine exposed human umbilical vein endothelial cells (HUVECs). Inhibitors to MEK/ERK (U0126) or Src (PP2) are used to determine the contribution of kinase signaling pathways.

MAIN OUTCOME MEASURES

Decreases in HUVEC Ca2+ signaling or monolayer resistance measure endothelial dysfunction. Reversal of endothelial dysfunction by kinase inhibitors reveals the respective contibutions of MEK/ERK and Src kinase.

RESULTS

We show that Src inhibition protects Ca2+ signaling responses against insults induced by VEGF165, bFGF, PlGF, TNFα, and IL-1β. Additionally, we show that Src inhibition protects the endothelial monolayer from the full impact of TNFα insult. Further, we find that MEK/ERK inhibition does not offer protection from growth factor-mediated endothelial dysfunction.

CONCLUSIONS

The results of this study suggest cytokine and growth factor-stimulated Src kinase plays a partial role on promoting endothelial dysfunction in HUVECs.

Identification of novel first-trimester serum biomarkers for early prediction of preeclampsia

BACKGROUND

Preeclampsia (PE) is a leading cause of maternal and perinatal mortality and morbidity worldwide, but effective early prediction remains a challenge due to the lack of reliable biomarkers.

METHODS

Based on the extensive human biobank of our large-scale assisted reproductive cohort platform, the first-trimester serum levels of 48 cytokines, total immunoglobulins (Igs), anti-phosphatidylserine (aPS) antibodies, and several previously reported PE biomarkers [including placental growth factor (PlGF), soluble fms-like tyrosine kinase-1 (sFlt-1), and activin A] were measured in 34 women diagnosed with PE and 34 matched normotensive controls.

RESULTS

The PE group has significantly higher first-trimester serum levels of interleukin (IL)-2Rα, IL-9, tumor necrosis factor-β (TNF-β), RANTES, hepatocyte growth factor (HGF), total IgM, and total IgG, and aPS IgG optical density (OD) value, as well as lower first-trimester serum levels of PlGF and total IgA and aPS-IgG immune complexes (IC) OD value than the control group. Combining top five first-trimester serum biomarkers (total IgM, total IgG, PlGF, aPS IgG, and total IgA) achieved superior predictive value [area under the curve (AUC) and 95% confidence interval (CI) 0.983 (0.952-1.000), with a sensitivity of 100% and a specificity of 94.1%] for PE development compared to PlGF and PlGF/sFlt-1 independently [AUC and 95% CI 0.825 (0.726-0.924) and 0.670 (0.539-0.800), respectively].

CONCLUSION

We identified novel first-trimester serum biomarkers and developed an effective first-trimester prediction model using immune-related factors and PlGF for PE, which could facilitate the development of early diagnostic strategies and provide immunological insight into the further mechanistic exploration of PE.

Mononuclear Cells Negatively Regulate Endothelial Ca2+ Signaling

Endothelial Ca2+ signaling has important roles to play in maintaining pregnancy associated vasodilation in the utero-placenta. Inflammatory cytokines, often elevated in vascular complications of pregnancy, negatively regulate ATP-stimulated endothelial Ca2+ signaling and associated nitric oxide production. However, the role of direct engagement of immune cells on endothelial Ca2+ signaling and therefore endothelial function is unclear. To model immune-endothelial interactions, herein, we evaluate the effects of peripheral blood mononuclear cells (PBMCs) in short-term interaction with human umbilical vein endothelial cells (HUVECs) on agonist-stimulated Ca2+ signaling in HUVECs. We find that mononuclear cells (10:1 and 25:1 mononuclear: HUVEC) cause decreased ATP-stimulated Ca2+ signaling; worsened by activated mononuclear cells possibly due to increased cytokine secretion. Additionally, monocytes, natural killers, and T-cells cause decrease in ATP-stimulated Ca2+ signaling using THP-1 (monocyte), NKL (natural killer cells), and Jurkat (T-cell) cell lines, respectively. PBMCs with Golgi-restricted protein transport prior to interaction with endothelial cells display rescue in Ca2+ signaling, strongly suggesting that secreted proteins from PBMCs mediate changes in HUVEC Ca2+ signaling. We propose that endothelial cells from normal pregnancy interacting with PBMCs may model preeclamptic endothelial-immune interaction and resultant endothelial dysfunction.

NLRP3 inflammasome in peripheral blood monocytes as a risk factor for early -onset preeclampsia

INTRODUCTION

As a leading cause of pregnancy and fetal mortality, pre-eclampsia impacts about 5-8% of pregnancies globally. To date, few studies have focused on the role played by (NOD)-like receptors protein 3 (NLRP3) in peripheral blood in early-onset pre-eclampsia (PE). In this study, we investigated whether NLRP3 expression in monocytes before 20 weeks of gestation was associated with an increased risk of early-onset PE.

METHODOLOGY

During the study period from 2019 to 2021, women with singleton pregnancies were enrolled in this prospective study at the General Hospital of Northern Theater Command. A generalized additive model (GAM) and logistic regression models were applied to determine any association between NLRP3 and the risk of early-onset PE.

RESULTS

In total, 571 and 48 subjects were included in the control and pre-eclampsia groups, respectively. The GAM and logistic regression models showed that NLRP3 was a significant factor for PE occurrence. The area under the curve, accuracy, specificity, sensitivity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio were 0.86, 0.82, 0.95, 0.72, 15.17, 0.29, and 52.0, respectively.

CONCLUSION

The monitoring for NLRP3 in peripheral blood may be a potential, prospectively identifying risk factor for preeclampsia.

Association of IL-27 gene rs153109 and rs17855750 polymorphisms with preeclampsia susceptibility and severity: Meta-analysis and trial sequential analysis

BACKGROUND

The aim of this meta-analysis is to evaluate the association of interleukin-27 gene rs153109 and rs17855750 polymorphisms with preeclampsia susceptibility and severity.

METHODS

Web of Science, PubMed, Embase, CBM, WanFang Data, CNKI, and VIP database were used for retrieving. After screening with our inclusion and exclusion criteria, data extraction and quantity evaluation were performed by 2 independent authors. Included case-control studies were used for meta-analysis by RevMan 5.4, and sensitivity analysis was carried out through 1-by-1 exclusion procedure. If heterogeneity exists, then random effects model was used; otherwise, fixed effect model was used. Publication bias analysis was performed using Begg test and Egger test. Trial sequential analysis was performed using trial sequential analysis 0.9.5.10 Beta.

RESULTS

A total of 5 articles were included. The heterogeneity was high across most models during the meta-analysis. Meta-analysis results related to preeclampsia susceptibility showed that P values of all the models were higher than .05, while for meta-analysis results related to preeclampsia severity showed that P values of all the models were higher than .05 except for TT versus TG + GG and TT versus TG models of rs17855750 group. The sensitivity of the meta-analysis was high, and trial sequential analysis showed the possibility of false negative results. No obvious publication bias was found.

CONCLUSIONS

There is no obvious association between interleukin-27 gene rs153109 and rs17855750 polymorphisms and preeclampsia susceptibility or severity. However, more multi-center and large sample case-control studies are expected to be carried out to verify our conclusion in the future.

Distinct cytokine profiles in patients with preeclampsia

OBJECTIVE

Preeclampsia (PE) is a common but serious pregnancy complication that adversely affects both maternal and fetal health. However, the mechanisms of its pathogenesis remain unclear, and effective biomarkers for early diagnosis are still lacking.

METHODS

In this retrospective study, comprehensive bioinformatic analysis and logistic regression analysis were used to compare profiles of 48 serum cytokines in 27 PE patients with those in 41 normotensive pregnant subjects.

RESULTS

The results revealed that serum cytokine profiles accumulated to different levels between the two groups, which had significant correlations with the clinical features of PE. Nine cytokines with high discriminatory capacity for diagnosising PE (AUC ≥ 0.7) were selected for inclusion in a multivariate logistic regression model for PE and calculated as a probability diagnostic formula. This model constructed from the panel of nine cytokines had better diagnostic performance than any individual cytokine (AUC = 0.97, 95% CI 0.94-1.00, P < 0.0001), with a sensitivity of 96.30% and a specificity of 90.24%.

CONCLUSIONS

The set of cytokine profiles and risk assessment model described here can serve as a basis for developing early clinical diagnostic and therapeutic strategies for PE.

Fatty acids in normal and pathological pregnancies

Long chain fatty acids, namely omega-3 and omega-6, are essential fatty acids and are necessary for proper pregnancy progression and fetal growth and development. Maternal fatty acid consumption and release of fatty acids from lipid stores provide increased availability of fatty acids for the placenta to transport to the growing fetus. Both omega-3 and omega-6 fatty acids are then utilized for generation of signaling molecules, such as eicosanoids, and for promoting of growth and developmental, most notably in the nervous system. Perturbations in fatty acid concentration and fatty acid signaling have been implicated in three major pregnancy complications - gestational diabetes, preeclampsia, and preterm birth. In this review we discuss the growing literature surrounding the role of fatty acids in normal and pathological pregnancies. Differences in maternal, placental, and fetal fatty acids and molecular regulation of fatty acid signaling and transport are presented. A look into novel fatty acid-based therapies for each of the highlighted disorders are discussed, and may present exciting bench to bedside alternatives to traditional pharmacological intervention.

Identification of mRNA-, circRNA- and lncRNA- Associated ceRNA Networks and Potential Biomarkers for Preeclampsia From Umbilical Vein Endothelial Cells

Objective

The etiology and pathogenesis of preeclampsia (PE) remain unclear, and ideal biomarkers for the early detection of PE are scarce. The involvement of the competing endogenous RNA (ceRNA) hypothesis in PE is only partially understood. The present study aimed to delineate a regulatory network in PE comprised of messenger RNAs (mRNAs), circular RNAs (circRNAs), long non-coding RNAs (lncRNAs), and microRNAs (miRNAs) via ceRNA profiles from human umbilical vein endothelial cells (HUVECs) to further reveal the pathogenesis of PE and potential biomarkers.

Methods

Differentially expressed mRNAs, circRNAs, and lncRNAs were detected in HUVECs from early onset preeclampsia (EOPE) cases (n = 4) and normal pregnancies (n = 4) by microarray analysis. Bioinformatics analysis was performed to systematically analyze the data, and a relevant ceRNA network was constructed. RNAs (ANGPT2, LIPG, hsa_circ_0025992, hsa_circ_0090396, hsa_circ_0066955, hsa_circ_0041203, hsa_circ_0018116, lnc-C17orf64-1:1, lnc-SLC27A2-2:1, and lnc-UEVLD-5:1) were validated by quantitative real-time PCR (qRT-PCR) in 10 pairs of HUVECs and placental tissues from PE patients and normal pregnancies. Furthermore, expression of hsa_circ_0025992 was detected in maternal peripheral blood samples from PE patients (n = 24) and normal pregnancies (n = 30) to confirm its potential as a novel biomarker. The receiver operating characteristic (ROC) curve was applied to analyze its diagnostic value.

Results

Compared with HUVECs from normal pregnancies, HUVECs from EOPE cases had 33 differentially expressed mRNAs (DEmRNAs), 272 DEcircRNAs, and 207 DElncRNAs. GO and KEGG analyses of the DERNAs revealed the biological processes and pathways involved in PE. Based on the microarray data and the predicted miRNAs, a ceRNA network was constructed with four mRNAs, 34 circRNAs, nine lncRNAs, and 99 miRNAs. GO and KEGG analyses of the network reinforced the crucial roles of metabolic disorders, the p53 and JAK/STAT signaling pathways in PE. In addition, ROC analysis indicated that hsa_circ_0025992 could be used as a novel biomarker for PE.

Conclusion

A novel ceRNA network was revealed in PE, and the potential of hsa_circ_0025992 to serve as a new biomarker was confirmed.