Negative regulation of soluble Flt-1 and soluble endoglin release by heme oxygenase-1

Prevention of preeclampsia

Preeclampsia is a relatively common pregnancy complication and constitutes a major cause of morbidity and mortality for mothers and children worldwide. It disproportionally affects low-resource countries. Appropriate identification of individuals at increased risk and prevention of the disease and its complications remain healthcare and research priorities, and the investigation of potential interventions to prevent preeclampsia has driven much of the obstetric research in recent decades. In this article, we review the scientific literature on the topic, highlighting established benefits and remaining questions regarding different non-pharmacological and pharmacological strategies, including exercise, the timing of birth, aspirin and calcium use, among others, as well as potential novel therapies under investigation.

Absence of Heme Oxygenase-1 Affects Trophoblastic Spheroid Implantation and Provokes Dysregulation of Stress and Angiogenesis Gene Expression in the Uterus

The enzyme heme oxygenase-1 (HO-1) is pivotal in reproductive processes, particularly in placental and vascular development. This study investigated the role of HO-1 and its byproduct, carbon monoxide (CO), in trophoblastic spheroid implantation. In order to deepen our understanding of the role of HO-1 during implantation, we conducted in vivo experiments on virgin and pregnant mice, aiming to unravel the cellular and molecular mechanisms. Using siRNA, HO-1 was knocked down in JEG-3 and BeWo cells and trophoblastic spheroids were generated with or without CO treatment. Adhesion assays were performed after transferring the spheroids to RL-95 endometrial epithelial cell layers. Additionally, angiogenesis, stress, and toxicity RT2-Profiler™ PCR SuperArray and PCR analyses were performed in uterine murine samples. HO-1 knockdown by siRNA impeded implantation in the 3D culture model, but this effect could be reversed by CO. Uteruses from virgin Hmox1-/- females exhibited altered expression of angiogenesis and stress markers. Furthermore, there was a distinct expression pattern of cytokines and chemokines in uteruses from gestation day 14 in Hmox1-/- females compared to Hmox1+/+ females. This study strongly supports the essential role of HO-1 during implantation. Moreover, CO appears to have the potential to compensate for the lack of HO-1 during the spheroid attachment process. The absence of HO-1 results in dysregulation of angiogenesis and stress-related genes in the uterus, possibly contributing to implantation failure.

INOVASIA Study: A Randomized Open Controlled Trial to Evaluate Pravastatin to Prevent Preeclampsia and Its Effects on sFlt1/PlGF Levels

OBJECTIVES

 This study aimed to evaluate the effect of pravastatin to prevent preeclampsia (PE) in pregnant women at a high risk of developing PE and the maternal and perinatal outcomes and the soluble fms-like tyrosine kinase 1/placental growth factor (sFlt1/PlGF) ratio.

STUDY DESIGN

 This is an open-labeled randomized controlled trial (RCT), a part of INOVASIA (Indonesia Pravastatin to Prevent Preeclampsia study) trial. Pregnant women at a high risk of developing PE were recruited and randomized into an intervention group (40) and a control group (40). The inclusion criteria consisted of pregnant women with positive clinical risk factor and abnormal uterine artery Doppler examination at 10 to 20 weeks' gestational age. The control group received low dose aspirin (80 mg/day) and calcium (1 g/day), while the intervention group received additional pravastatin (20-mg twice daily) starting from 14 to 20 weeks' gestation until delivery. Research blood samples were collected before the first dose of pravastatin and before delivery. The main outcome was the rate of maternal PE, maternal-perinatal outcomes, and sFlt-1, PlGF, sFlt-1/PlGF ratio, and soluble endoglin (sEng) levels.

RESULTS

 The rate of PE was (nonsignificantly) lower in the pravastatin group compared with the control group (17.5 vs. 35%). The pravastatin group also had a (nonsignificant) lower rate of severe PE, HELLP (hemolysis, elevated liver enzymes and low platelets) syndrome, acute kidney injury, and severe hypertension. The rate of (iatrogenic) preterm delivery was significantly (p = 0.048) lower in the pravastatin group (n = 4) compared with the controls (n = 12). Neonates in the pravastatin group had significantly higher birth weights (2,931 ± 537 vs. 2,625 ± 872 g; p = 0.006), lower Apgar's scores < 7 (2.5 vs. 27.5%, p = 0.002), composite neonatal morbidity (0 vs. 20%, p = 0.005), and NICU admission rates (0 vs. 15%, p = 0.026). All biomarkers show a significant deterioration in the control group compared with nonsignificant changes in the pravastatin group.

CONCLUSION

 Pravastatin holds promise in the secondary prevention of PE and placenta-mediated adverse perinatal outcomes by improving the angiogenic imbalance.

KEY POINTS

· Prophylactic pravastatin was associated with a significantly lower rate of adverse perinatal outcome.. · The sFlt1/PlGF ratio stabilized in the pravastatin group compared with a deterioration in the control group.. · Pravastatin holds promise in the secondary prevention of PE and placenta-mediated adverse perinatal outcomes..

Do Genetic Variants Modify the Effect of Smoking on Risk of Preeclampsia in Pregnancy?

OBJECTIVE

 Maternal smoking is associated with as much as a 50% reduced risk of preeclampsia, despite increasing risk of other poor pregnancy outcomes that often co-occur with preeclampsia, such as preterm birth and fetal growth restriction. Researchers have long sought to understand whether this perplexing association is biologically based, or a result of noncausal mechanisms. We examined whether smoking-response genes modify the smoking-preeclampsia association to investigate potential biological explanations.

STUDY DESIGN

 We conducted a nested case-control study within the Norwegian Mother, Father and Child Birth Cohort (1999-2008) of 2,596 mother-child dyads. We used family-based log-linear Poisson regression to examine modification of the maternal smoking-preeclampsia relationship by maternal and fetal single nucleotide polymorphisms involved in cellular processes related to components of cigarette smoke (n = 1,915 with minor allele frequency ≥10%). We further investigated the influence of smoking cessation during pregnancy.

RESULTS

 Three polymorphisms showed overall (p < 0.001) multiplicative interaction between smoking and maternal genotype. For rs3765692 (TP73) and rs10770343 (PIK3C2G), protection associated with smoking was reduced with two maternal copies of the risk allele and was stronger in continuers than quitters (interaction p = 0.02 for both loci, based on testing 3-level smoking by 3-level genotype). For rs2278361 (APAF1) the inverse smoking-preeclampsia association was eliminated by the presence of a single risk allele, and again the trend was stronger in continuers than in quitters (interaction p = 0.01).

CONCLUSION

 Evidence for gene-smoking interaction was limited, but differences by smoking cessation warrant further investigation. We demonstrate the potential utility of expanded dyad methods and gene-environment interaction analyses for outcomes with complex relationships between maternal and fetal genotypes and exposures.

KEY POINTS

· Maternal and fetal genotype may differentially influence preeclampsia.. · Smoking-related genes did not strongly modify smoking-preeclampsia association.. · Smoking cessation reduced strength of gene by smoking interactions..

Upregulation of autotaxin by oxidative stress via Nrf2 activation: A novel insight into the compensation mechanism in preeclamptic placenta

The response of autotaxin (ATX)-lysophosphatidic acid (LPA) signaling system to placental oxidative stress (OS) and its significance to preeclampsia were investigated. For this purpose, oxidative stress index (OSI) and ATX levels were measured in the serum of pregnant women with preeclampsia. The expression levels of ATX and LPA receptors were assessed in trophoblast cells under high OS and glucose deprivation/re-oxygenation (OGD/R) conditions, with particular emphasis on the antioxidative nuclear factor erythroid 2-related factor 2 (NRF2) pathway. The influence of ATX-LPA signaling on cell migration was also evaluated using the wound healing assay. ATX concentrations and OSI in the serum were found to be elevated in preeclamptic women. The serum ATX levels were also positively correlated with OSI. Trophoblast cells responded to OS by increasing ATX mRNA expression concomitantly with intranuclear translocation of Nrf2, whereas inhibition of Nrf2 activation reverted this effect. The ATX-LPA signaling pathway facilitated trophoblast cell motility after Nrf2 activation. In conclusion, OS accumulation in preeclamptic placenta may activate the ATX-LPA system in trophoblasts via the Nrf2 pathway to sustain trophoblast functionality.

Long-term neurodevelopmental follow-up of children exposed to pravastatin in utero

BACKGROUND

Preeclampsia, especially before term, increases the risk of child neurodevelopmental adverse outcomes. Biological plausibility, preclinical studies, and pilot clinical trials conducted by the Eunice Kennedy Shriver National Institute of Child Health and Human Development and the Obstetric-Fetal Pharmacology Research Centers Network support the safety and use of pravastatin to prevent preeclampsia.

OBJECTIVE

This study aimed to determine the effect of antenatal pravastatin treatment in high-risk pregnant individuals on their child's health, growth, and neurodevelopment.

STUDY DESIGN

This was an ancillary follow-up cohort study of children born to mothers who participated in the Obstetric-Fetal Pharmacology Research Centers Network pilot trials of pravastatin vs placebo in individuals at high risk of preeclampsia (ClinicalTrials.gov; identifier NCT01717586). After obtaining written informed consent (and assent as appropriate), the parent was instructed to complete the Child Behavior Checklist. To assess the child's motor, cognitive, and developmental outcomes, a certified and blinded study psychologist completed child motor, cognitive, emotional, and behavioral assessments using validated tools. Given the small number of individuals in the studies, the 10- and 20-mg pravastatin groups were combined into 1 group, and the results of the pravastatin group were compared with that of the placebo group.

RESULTS

Of 40 children born to mothers in the original trial, 30 (15 exposed in utero to pravastatin and 15 to placebo) were enrolled in this follow-up study. The time of follow-up, which was 4.7 years (interquartile range, 2.5-6.9), was not different between children in the pravastatin group and children in the placebo group. There was no difference in the child's body mass index percentiles per sex and corrected age, the rates of extremes of body mass index percentiles, or the report of any other medical or developmental complications between the 2 groups. No child born in the pravastatin group had any limitation in motor assessment compared with 2 children (13.3%) who walked with difficulty and 4 children (26.7%) who had reduced manual abilities in the placebo group. Moreover, children born to mothers who received pravastatin had a higher general mean conceptual ability score (98.2±16.7 vs 89.7±11.0; P=.13) and a lower frequency (15.4% vs 35.7%; P=.38) of having a score of <85 (ie, 1 standard deviation lower than the mean) compared with those in the placebo group. Finally, there was no difference in the parents' report on the Child Behavior Checklist between the 2 groups.

CONCLUSION

This study reported on the long-term neuromotor, cognitive, and behavioral outcomes among children exposed to pravastatin in utero during the second and third trimesters of pregnancy. Although the data were limited by the original trial's sample size, no identifiable long-term neurodevelopmental safety signal was evident with the use of pravastatin during pregnancy. This favorable neonatal risk-benefit analysis justifies continued research using pravastatin in clinical trials.

New Ideas for the Prevention and Treatment of Preeclampsia and Their Molecular Inspirations

Preeclampsia (PE) is a pregnancy-specific disorder affecting 4-10% of all expectant women. It greatly increases the risk of maternal and foetal death. Although the main symptoms generally appear after week 20 of gestation, scientific studies indicate that the mechanism underpinning PE is initiated at the beginning of gestation. It is known that the pathomechanism of preeclampsia is strongly related to inflammation and oxidative stress, which influence placentation and provoke endothelial dysfunction in the mother. However, as of yet, no "key players" regulating all these processes have been discovered. This might be why current therapeutic strategies intended for prevention or treatment are not fully effective, and the only effective method to stop the disease is the premature induction of delivery, mostly by caesarean section. Therefore, there is a need for further research into new pharmacological strategies for the treatment and prevention of preeclampsia. This review presents new preventive methods and therapies for PE not yet recommended by obstetrical and gynaecological societies. As many of these therapies are in preclinical studies or under evaluation in clinical trials, this paper reports the molecular targets of the tested agents or methods.

Understanding the molecular mechanisms of statin pleiotropic effects

Statins represent the cornerstone of pharmacotherapy for the prevention of atherosclerotic cardiovascular disease. These medications not only reduce low-density lipoprotein cholesterol (LDL-C) via inhibition of 3-hydroxy-3-methylglutarate attached to CoA reductase, the key rate-limiting step in the cholesterol biosynthetic pathway, but also upregulate expression of the low-density lipoprotein receptor, improving serum clearance. Given LDL-C is a causal risk factor for the development of atherosclerosis, these complementary mechanisms largely explain why statin therapy leads to reductions in major adverse cardiovascular events. However, decades of basic and clinical research have suggested that statins may exert other effects independent of LDL-C lowering, termed pleiotropic effects, which have become a topic of debate among the scientific community. While some literature suggests statins may improve plaque stability, reduce inflammation and thrombosis, decrease oxidative stress, and improve endothelial function and vascular tone, other studies have suggested potential harmful pleiotropic effects related to increased risk of muscle-related side effects, diabetes, hemorrhagic stroke, and cognitive decline. Furthermore, the introduction of newer, non-statin LDL-C lowering therapies, including ezetimibe, proprotein convertase subtilisin/Kexin Type 9, and bempedoic acid, have challenged the statin pleiotropy theory. This review aims to provide a historical background on the development of statins, explore the mechanistic underpinnings of statin pleiotropy, review the available literature, and provide up to date examples that suggest statins may exert effects outside of LDL-C lowering and the cardiovascular system.

sFlt-1-enriched exosomes induced endothelial cell dysfunction and a preeclampsia-like phenotype in mice

Preeclampsia (PE) is a hypertensive disorder of pregnancy characterized by maternal endothelial dysfunction and end-organ damage. Our previous work demonstrated that PE patient-derived exosomes contained higher levels of soluble FMS-like tyrosine kinase-1 (sFlt-1) and significantly induced endothelial dysfunction and PE development. However, the mechanisms underlying the effect of sFlt-1-enriched exosomes (sFlt-1-Exo) on PE development are poorly characterized. Here, we revealed that trophoblast-derived sFlt-1-Exo treatment induced significant inhibition of human umbilical vein endothelial cell (HUVEC) migration and tube formation, as well as an increase in sFlt-1 secretion. Mechanistically, we found that the increased sFlt-1 secretion in the cell culture medium was attributed to enhanced transcription of sFlt-1 in HUVECs. Importantly, we observed that treating pregnant mice with sFlt-1-Exo or recombinant mouse sFlt-1 triggered a preeclampsia-like phenotype, characterized by elevated blood pressure, proteinuria, increased plasma sFlt-1 and adverse pregnancy outcomes. These results strongly suggested that sFlt-1-Exo-induced endothelial dysfunction could be partially attributed to the upregulation of sFlt-1 in endothelial cells, potentially leading to the development of a preeclampsia-like phenotype in mice.

Vitamin E protects against the modulation of TNF-α-AMPK axis and inhibits pancreas injury in a rat model of L-arginine-induced acute necrotising pancreatitis

BACKGROUND

Acute pancreatitis (AP) associated with the modulation of TNF-α-AMPK axis in the presence and absence of vitamin E has not been investigated before.

MATERIAL AND METHODS

Rats were either injected with L-arginine (2.5 gm/kg) before being sacrificed after 48 h or were pre-treated with vitamin E (60 mg/kg) and continued receiving vitamin E until the end of the experiment.

RESULTS

AP was developed as demonstrated by infiltration of inflammatory cells and profound pancreas tissue damage, which were substantially protected by vitamin E. In addition, L-arginine injections significantly (p < .0001) increased the expression of TNF-α mRNA and protein, and decreased phospho-AMPK and IL-10 mRNA and protein that was significantly (p < .0001) protected by vitamin E. Furthermore, vitamin E inhibited L-arginine-induced blood levels of LDH, amylase, and myeloperoxidase.

CONCLUSIONS

L-arginine-induced acute pancreatitis modulates TNF-α-AMPK axis, IL-10 and other AP biomarkers, which is protected by vitamin E; thus, may offer therapeutic potential in humans.

Statins in pre-eclampsia or fetal growth restriction: A systematic review and meta-analysis on maternal blood pressure and fetal growth across species

BACKGROUND

Several human randomised controlled trials (RCTs) are investigating the effects of statins on pre-eclampsia (PE) and fetal growth restriction (FGR). This cross-species meta-analysis summarises the preclinical evidence of statin use for PE and FGR.

OBJECTIVES

Evaluate the effects of statins on maternal blood pressure (MBP) and birthweight (BW) in pregnancies complicated by PE or FGR.

SEARCH STRATEGY

PubMed and Embase.com were searched on 10 May 2022 using 'statins' and 'pregnancy'.

SELECTION CRITERIA

We included RCTs and cohorts with matched control groups as well as animal studies.

DATA COLLECTION AND ANALYSIS

The main outcomes were MBP in mmHg and BW in grams. The standardised mean difference (SMD) with a 95% confidence interval (CI) was calculated. Subgroup analyses on species, statin, dose, timing and route of administration were performed if subgroups included at least three studies.

MAIN RESULTS

Our data included one human and 12 animal studies. Prenatal administration of statins significantly reduced MBP during pregnancy (SMD  -2.49 mmHg [95% CI -4.26 to -0.71], p = 0.01). There was no significant effect of statins on BW (SMD 0.69 [95% CI -0.65 to 2.03], p = 0.28). Our subgroup analyses showed no effect on MBP of different doses, species or route of administration.

CONCLUSIONS

Our cross-species meta-analyses demonstrate that statins only reduce maternal blood pressure in rodent pregnancies complicated by pre-eclampsia or fetal growth restriction and have no effect on birthweight across species. The broad confidence intervals, inconsistent direction of the observed effects across the studies and large risk of bias lead us to conclude that a solid base for further human RCTs is lacking.

Pre-Existing Diabetes Mellitus, Hypertension and KidneyDisease as Risk Factors of Pre-Eclampsia: A Disease of Theories and Its Association with Genetic Polymorphism

Pre-existing diabetes, hypertension and kidney disorders are prominent risk factors of pre-eclampsia (PE). It is a multifactorial pregnancy disorder associated with high blood pressure, proteinuria, and multiorgan failure, which develops after the 20th week of pregnancy. It is one of the most feared pregnancy disorders, as it consumes thousands of fetomaternal lives per annum. According to clinical and pathological studies, the placenta appears to be a key player in the pathogenesis of PE; however, the exact origin of this disorder is still under debate. Defective placentation and angiogenesis are the hallmarks of PE progression. This angiogenic imbalance, together with maternal susceptibility, might determine the severity and clinical presentation of PE. This article comprehensively examines the mechanisms of pathogenesis of PE and current evidence of the factors involved in its progression. Finally, this article will explore the genetic association of PE, various candidate genes, their proposed mechanisms and variants involved in its pathogenesis.

Pravastatin and placental insufficiency associated disorders: A systematic review and meta-analysis

Background: Uteroplacental insufficiency associated disorders, such as preeclampsia, fetal growth restriction and obstetrical antiphospholipid syndrome, share pathophysiology and risk factors with cardiovascular diseases treated with statins. Objective: To evaluate pregnancy outcomes among women with uteroplacental insufficiency disorders who were treated with statins. Search Strategy: Electronic databases were searched from inception to January 2022 Selection Criteria: Cohort studies and randomized controlled trials. Data collection and analysis: Pooled odds ratios were calculated using a random-effects model; meta-regression was utilized when applicable. Main Results: The analysis included ten studies describing 1,391 women with uteroplacental insufficiency disorders: 703 treated with pravastatin and 688 not treated with statins. Women treated with pravastatin demonstrated significant prolongation of pregnancy (mean difference 0.44 weeks, 95%CI:0.01-0.87, p = 0.04, I2 = 96%) and less neonatal intensive care unit admissions (OR = 0.42, 95%CI: 0.23-0.75, p = 0.004, I2 = 25%). In subgroup analysis, prolongation of pregnancy from study entry to delivery was statistically significant in cohort studies (mean difference 8.93 weeks, 95%CI:4.22-13.95, p = 0.00) but not in randomized control studies. Trends were observed toward a decrease in preeclampsia diagnoses (OR = 0.54, 95%CI:0.27-1.09, p = 0.09, I = 44%), perinatal death (OR = 0.32, 95%CI:0.09-1.13, p = 0.08, I2 = 54%) and an increase in birth weight (mean difference = 102 g, 95%CI: -14-212, p = 0.08, I2 = 96%). A meta-regression analysis demonstrated an association between earlier gestational age at initiation of treatment and a lower risk of preeclampsia development (R2 = 1). Conclusion: Pravastatin treatment prolonged pregnancy duration and improved associated obstetrical outcomes in pregnancies complicated with uteroplacental insufficiency disorders in cohort studies. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/ identifier CRD42020165804 17/2/2020.

Emerging pharmacologic interventions for pre-eclampsia treatment

INTRODUCTION

Pre-eclampsia is a serious pregnancy complication and a major global concern for the mortality of both mother and fetus. Existing symptomatic treatments do not delay disease progression; thus, timely delivery of the baby is the most effective measure. However, the risk of various maternal and fetal injuries remains.

AREAS COVERED

In this review, we summarize the potential strategies for pharmacologic interventions in pre-eclamptic therapy. Specifically, we discuss the pathophysiological process of various effective candidate therapeutics that act on potential pathways and molecular targets to inhibit key stages of the disease. We refer to this pathogenesis-focused drug discovery model as a pathogenesis-target-drug (P-T-D) strategy. Finally, we discuss the introduction of nanotechnologies to improve the safety and efficacy of therapeutics via their specific placental targeting ability and placental retention effects.

EXPERT OPINION

Despite the active development of novel pharmacological treatments based on our current knowledge of pre-eclamptic pathogenesis, investigations are still in the early phase. Thus, further exploration of the pathological mechanisms, integrated with the P-T-D strategy and novel nanosystems, could encourage the development of more effective and safer strategies. Such advances could lead to a shift from expectant management to mechanistic-based therapy for pre-eclampsia.

The preventive effect of low-dose aspirin in a PPAR-γ antagonist treated mouse model of preeclampsia

Background

Preeclampsia (PE) is one of the leading causes of maternal and perinatal mortality and morbidity. Low-dose aspirin (LDA) is the most widely used drug to prevent PE, but the recommended dose of LDA varies according to different guidelines. Peroxisome proliferator-activated receptor (PPAR)-γ is involved in the formation of the placenta during pregnancy and is expressed in women with severe PE. In the present study, Our purpose was to investigate whether aspirin intervention in preeclampsia was related to PPAR-γ.

Methods

We administered pregnant mice with PPAR-γ-specific antagonist(T0070907) 2 mg/kg/d at 8.5–12.5 days of pregnancy. Mice treated with T0070907 developed key features of preeclampsia. Two doses of LDA (10 mg/kg/d and 20 mg/kg/d) were administered to the mice with a PE phenotype for intervention.

Results

LDA effectively decreased the increase in blood pressure in mice caused by T0070907 and decreased urinary protein levels and the urinary protein/creatinine ratio. LDA also inhibited the overexpression of endoglin and IL-β treated by T0070907. In addition, LDA evidently increased the placental weight and alleviates the degree of placental lesions of placenta and kidney. LDA alleviated the inhibition of PPAR-γ mRNA expression. The beneficial effect of 20 mg LDA was significantly better than that of 10 mg.

Conclusions

(1) LDA has a preventive effect against PE treated by PPAR-γ antagonist. (2) The preventive effect of LDA against PE is dose-dependent.

The effect of nicotine-containing products and fetal sex on placenta-associated circulating midpregnancy biomarkers

Background

In utero exposure to nicotine, largely assessed by smoking, is a risk factor for impaired offspring health, while potential effects of non-combustible nicotine use such as snus (oral moist tobacco), are less well-known. Maternal serum concentrations of placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1) may be viewed as “placenta health markers”, known to differ by fetal sex. Maternal smoking during pregnancy has been associated with lower levels of circulating sFlt-1, while the effect of snus on placenta-associated angiogenic factors is unknown. Our aim was to explore if snus and/or smoking exposure was associated with midpregnancy maternal levels of sFlt-1, PlGF and sFlt-1/PlGF ratio if these associations were modified by fetal sex.

Methods

Midpregnancy (16–22 gestational weeks) serum from 2603 Scandinavian women enrolled in the population-based multi-center PreventADALL (Preventing Atopic Dermatitis and ALLergies in children) study was analysed for sFlt-1 and PlGF concentrations by electrochemiluminescence, deriving the sFlt-1/PGF ratio. Nicotine use was assessed by electronic questionnaires at enrollment in 2278 of the women. Univariable and multivariable linear regression models on log transformed outcomes were used to assess the association between nicotine use and biomarker levels. Interaction terms were included to identify whether the associations were modified by fetal sex.

Results

Median sFlt-1, PlGF and sFlt-1/PlGF ratios among women with nicotine exposure information were similar to those of all included women and differed by fetal sex. Current snus use was significantly associated with reduced maternal circulating PlGF levels in adjusted analyses [β − 0.12, (95% CI − 0.20; 0.00) compared to never use, p = 0.020]. A significant interaction between fetal sex and snus exposure was observed for PIGF (p = 0.031). Prior or periconceptional snus use was significantly associated with PIGF in male fetus pregnancies [β − 0.05 (95% CI − 0.09 to (− 0.02)) and β − 0.07 (95% CI − 0.12 to (− 0.02)) compared to never use, p = 0.002]. Smoking was not significantly associated with any circulating biomarkers levels.

Conclusions

Midpregnancy maternal angiogenic profile differed by periconceptional snus use and fetal sex. Snus exposure, perceived as “safe” by users, before or during pregnancy seems to affect midpregnancy placental health in a sex dimorphic manner.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13293-022-00443-1.

Statins in Pregnancy: Can We Justify Early Treatment of Reproductive Aged Women?

PURPOSE OF REVIEW

Statins are the pillar of secondary prevention in reducing cardiovascular disease in high-risk adults. However, statin discontinuation is the standard recommendation in pregnant and lactating patients. This review evaluates whether we can justify the early treatment of reproductive aged women with statin therapy.

RECENT FINDINGS

Statins have several potential benefits including its antioxidant, anti-inflammatory, and anti-thrombogenic properties that may prevent the worsening of atherosclerosis in high-risk women. Nevertheless, most studies on statins and teratogenicity have a limited sample size and the effects of long-term statin use on fetal and neonatal health remain unknown. Not all statins may be safe and pravastatin's cholesterol-lowering properties may be too limited to provide much maternal benefit in pregnancy. While emerging evidence supports the use of pravastatin in pregnancy, we need to better assess the risk of early cardiovascular disease and acute progression of atherosclerosis before and during pregnancy to better understand the risks and benefits of statin use.

Systemic Maternal Human sFLT1 Overexpression Leads to an Impaired Foetal Brain Development of Growth-Restricted Foetuses upon Experimental Preeclampsia

The pregnancy disorder preeclampsia (PE) is characterized by maternal hypertension, increased level of circulating antiangiogenic soluble fms-like tyrosine kinase-1 (sFLT1), and reduced placental perfusion, leading to foetal growth restriction (FGR) and preterm birth. All these adverse effects are associated with neurocognitive disorders in the offspring. However, the direct interplay between increased antiangiogenesis during PE and disturbed foetal brain development independent of prematurity has not been investigated yet. To examine foetal brain development in sFLT1-related PE, hsFLT1/rtTA-transgenic mice with systemic (maternal or maternal/fetoplacental) human sFLT1 (hsFLT1) overexpression since 10.5 days postconception (dpc) were used, and histological and molecular analyses of foetal brains were performed at 18.5 dpc. Consequences of elevated hsFLT1 on placental/foetal vascularization and hypoxia of placentas and foetal brains were analysed using the hypoxia markers pimonidazole and hemeoxygenase-1 (HO-1). Immunohistochemical analysis revealed increased hypoxia in placentas of PE-affected pregnancies. Moreover, an increase in HO-1 expression was observed upon elevated hsFLT1 in placentas and foetal brains. PE foetuses revealed asymmetrical FGR by increased brain/liver weight ratio. The brain volume was reduced combined with a reduction in the cortical/hippocampal area and an increase of the caudate putamen and its neuroepithelium, which was associated with a reduced cell density in the cortex and increased cell density in the caudate putamen upon hsFLT1 overexpression. Mild influences were observed on brain vasculature shown by free iron deposits and mRNA changes in Vegf signalling. Of note, both types of systemic hsFLT1 overexpression (indirect: maternal or direct: maternal/fetoplacental) revealed similar changes with increasing severity of impaired foetal brain development. Overall, circulating hsFLT1 in PE pregnancies impaired uteroplacental perfusion leading to disturbed foetal oxygenation and brain injury. This might be associated with a disturbed cell migration from the caudate putamen neuroepithelium to the cortex which could be due to disturbed cerebrovascular adaption.

Procyanidin B2 ameliorates endothelial dysfunction and impaired angiogenesis via the Nrf2/PPARγ/sFlt-1 axis in preeclampsia

Preeclampsia is a severe complication of pregnancy characterized by variable degrees of placental malperfusion. A growing body of evidence indicates that soluble endoglin and soluble fms-like tyrosine kinase-1 (sFlt-1) play important pathophysiological roles in preeclampsia, causing endothelial dysfunction, hypertension, and multiorgan injury. A drug that is safe in pregnancy and inhibits placental sFlt-1 and soluble endoglin secretion would be an attractive treatment strategy for preeclampsia. Procyanidin B2, a bioactive food compound, has been reported to exert multiple beneficial functions. Placental explant cultures in vitro are useful for studying tissue functions including release of secretory components, pharmacology, toxicology, and disease processes. The reduced uterine perfusion pressure (RUPP) rat model has been widely used as a model of preeclampsia. We aimed to investigate the effect of procyanidin B2 on preeclampsia via using placental explant cultures and RUPP rat model. In this study, we demonstrated that procyanidin B2 reduced soluble endoglin and sFlt-1 secretion from human umbilical vein endothelial cells (HUVECs), primary trophoblasts, and placental explants from preeclamptic pregnancies. Moreover, procyanidin B2 alleviated endothelial dysfunction and impaired angiogenesis induced by sFlt-1, including increasing the migration, invasion and angiogenesis of endothelial cells and decreasing the expression of vascular cell adhesion molecule-1 (VCAM-1) and leukocyte adhesion on HUVECs. In addition, procyanidin B2 promoted nuclear factor erythroid 2-related factor 2 (Nrf2) nuclear accumulation and induced peroxisome proliferator-activated receptor γ (PPARγ) expression in primary placental tissues and endothelial cells. Importantly, Nrf2 specifically binds to the PPARγ promoter region (-1227/-1217) and enhances its transcriptional activity. Procyanidin B2 inhibits sFlt-1 secretion via the Nrf2/PPARγ axis. In the RUPP rat model of preeclampsia, procyanidin B2 attenuated RUPP-induced maternal angiogenic imbalance, hypertension and improved placental and fetal weight. Taken together, our results demonstrate that procyanidin B2 inhibits sFlt-1 secretion and ameliorates endothelial dysfunction and impaired angiogenesis via the Nrf2/PPARγ axis in preeclampsia. Procyanidin B2 may be a novel therapeutic agent for treatment of preeclampsia.

Pravastatin, proton-pump inhibitors, metformin, micronutrients, and biologics: new horizons for the prevention or treatment of preeclampsia

There has been increasing research momentum to identify new therapeutic agents for the prevention or treatment of preeclampsia, drugs that can affect the underlying disease pathophysiology. Molecular targets of candidate treatments include oxidative stress, antiangiogenic factors, and the angiotensin, nitric oxide, and proinflammatory pathways. The proposed treatments undergoing preclinical and clinical trial evaluation are thought to act on placental or endothelial disease or both. Most have adopted the pragmatic strategy of repurposing drugs. Of all the therapeutic agents proposed, pravastatin has received the most interest. There are preclinical studies showing that it has pleiotropic actions that favorably impact on multiple molecular targets and can resolve a preeclampsia phenotype in many animal models. An early phase clinical trial suggests that it may have therapeutic activity. Several large prevention trials are planned or ongoing and, when completed, could definitively address whether pravastatin can prevent preeclampsia. Proton-pump inhibitors, metformin, and sulfasalazine are other drugs with preclinical evidence of multiple molecular actions that could resolve the pathophysiology of preeclampsia. These agents are also currently being evaluated in clinical trials. There have been many recent preclinical studies identifying the potential of numerous natural compounds to treat preeclampsia, such as plant extracts and micronutrients that have potent anti-inflammatory or antioxidant activity. Recent preclinical studies have also proposed novel molecular-targeted strategies, such as monoclonal antibodies targeting tumor necrosis factor alpha, placental growth factor, and short interfering RNA technology, to silence the gene expression of soluble fms-like tyrosine kinase-1 or angiotensinogen. Other treatment approaches that have transitioned to human trials (ranging from single-arm to phase III trials that have been completed or are ongoing) include folic acid, nitric oxide donors (such as L-arginine), recombinant antithrombin III, digoxin immune antigen-binding fragment, and melatonin. There have been case series showing the removal of circulating soluble fms-like tyrosine kinase-1 may help stabilize the disease and prolong pregnancy. Interestingly, there are case reports suggesting that monoclonal antibody eculizumab (complement inhibitor) may have therapeutic potential. If new agents are discovered that are proven to be effective in preventing or treating preeclampsia, the potential to improve global maternal and perinatal health will be significant.

The role of statins in the prevention of preeclampsia

Preeclampsia is a common hypertensive disorder of pregnancy associated with considerable neonatal and maternal morbidities and mortalities. However, the exact cause of preeclampsia remains unknown; it is generally accepted that abnormal placentation resulting in the release of soluble antiangiogenic factors, coupled with increased oxidative stress and inflammation, leads to systemic endothelial dysfunction and the clinical manifestations of the disease. Statins have been found to correct similar pathophysiological pathways that underlie the development of preeclampsia. Pravastatin, specifically, has been reported in various preclinical and clinical studies to reverse the pregnancy-specific angiogenic imbalance associated with preeclampsia, to restore global endothelial health, and to prevent oxidative and inflammatory injury. Human studies have found a favorable safety profile for pravastatin, and more recent evidence does not support the previous teratogenic concerns surrounding statins in pregnancy. With reassuring and positive findings from pilot studies and strong biological plausibility, statins should be investigated in large clinical randomized-controlled trials for the prevention of preeclampsia.

Imbalances in circulating angiogenic factors in the pathophysiology of preeclampsia and related disorders

Preeclampsia is a devastating medical complication of pregnancy that can lead to significant maternal and fetal morbidity and mortality. It is currently believed that there is abnormal placentation in as early as the first trimester in women destined to develop preeclampsia. Although the etiology of the abnormal placentation is being debated, numerous epidemiologic and experimental studies suggest that imbalances in circulating angiogenic factors released from the placenta are responsible for the maternal signs and symptoms of preeclampsia. In particular, circulating levels of soluble fms-like tyrosine kinase 1, an antiangiogenic factor, are markedly increased in women with preeclampsia, whereas free levels of its ligand, placental, growth factor are markedly diminished. Alterations in these angiogenic factors precede the onset of clinical signs of preeclampsia and correlate with disease severity. Recently, the availability of automated assays for the measurement of angiogenic biomarkers in the plasma, serum, and urine has helped investigators worldwide to demonstrate a key role for these factors in the clinical diagnosis and prediction of preeclampsia. Numerous studies have reported that circulating angiogenic biomarkers have a very high negative predictive value to rule out clinical disease among women with suspected preeclampsia. These blood-based biomarkers have provided a valuable tool to clinicians to accelerate the time to clinical diagnosis and minimize maternal adverse outcomes in women with preeclampsia. Angiogenic biomarkers have also been useful to elucidate the pathogenesis of related disorders of abnormal placentation such as intrauterine growth restriction, intrauterine fetal death, twin-to-twin transfusion syndrome, and fetal hydrops. In summary, the discovery and characterization of angiogenic proteins of placental origin have provided clinicians a noninvasive blood-based tool to monitor placental function and health and for early detection of disorders of placentation. Uncovering the mechanisms of altered angiogenic factors in preeclampsia and related disorders of placentation may provide insights into novel preventive and therapeutic options.

The role of endoglin and its soluble form in pathogenesis of preeclampsia

Preeclampsia remains till today a leading cause of maternal and fetal morbidity and mortality. Pathophysiology of the disease is not yet fully elucidated, though it is evident that it revolves around placenta. Cellular ischemia in the preeclamptic placenta creates an imbalance between angiogenic and anti-angiogenic factors in maternal circulation. Endoglin, a transmembrane co-receptor of transforming growth factor β (TGF-β) demonstrating angiogenic effects, is involved in a variety of angiogenesis-dependent diseases with endothelial dysfunction, including preeclampsia. Endoglin expression is up-regulated in preeclamptic placentas, through mechanisms mainly induced by hypoxia, oxidative stress and oxysterol-mediated activation of liver X receptors. Overexpression of endoglin results in an increase of its soluble form in maternal circulation. Soluble endoglin represents the extracellular domain of membrane endoglin, cleaved by the action of metalloproteinases, predominantly matrix metalloproteinase-14. Released in circulation, soluble endoglin interferes in TGF-β1 and activin receptor-like kinase 1 signaling pathways and inhibits endothelial nitric oxide synthase activation, consequently deranging angiogenesis and promoting vasoconstriction. Due to these properties, soluble endoglin actively contributes to the impaired placentation observed in preeclampsia, as well as to the pathogenesis and manifestation of its clinical signs and symptoms, especially hypertension and proteinuria. The significant role of endoglin and soluble endoglin in pathophysiology of preeclampsia could have prognostic, diagnostic and therapeutic perspectives. Further research is essential to extensively explore the potential use of these molecules in the management of preeclampsia in clinical settings.

Iron Metabolism in Normal and Pathological Pregnancies and Fetal Consequences

Iron is required for energy production, DNA synthesis, and cell proliferation, mainly as a component of the prosthetic group in hemoproteins and as part of iron-sulfur clusters. Iron is also a critical component of hemoglobin and plays an important role in oxygen delivery. Imbalances in iron metabolism negatively affect these vital functions. As the crucial barrier between the fetus and the mother, the placenta plays a pivotal role in iron metabolism during pregnancy. Iron deficiency affects 1.2 billion individuals worldwide. Pregnant women are at high risk of developing or worsening iron deficiency. On the contrary, in frequent hemoglobin diseases, such as sickle-cell disease and thalassemia, iron overload is observed. Both iron deficiency and iron overload can affect neonatal development. This review aims to provide an update on our current knowledge on iron and heme metabolism in normal and pathological pregnancies. The main molecular actors in human placental iron metabolism are described, focusing on the impact of iron deficiency and hemoglobin diseases on the placenta, together with normal metabolism. Then, we discuss data concerning iron metabolism in frequent pathological pregnancies to complete the picture, focusing on the most frequent diseases.

Esomeprazole inhibits hypoxia/endothelial dysfunction–induced autophagy in preeclampsia

Preeclampsia (PE) affects 3 to 5% of pregnant women worldwide and is associated with fetal and maternal morbidity and mortality. Although a complete understanding of PE remains elusive, it has been widely accepted that a dysfunction of the placenta plays a key role in the pathogenesis of PE. In this study, we investigated the role of excessive placental autophagy during PE pathogenesis and explored whether esomeprazole ameliorates PE by inhibiting the autophagy in the placenta. The PE cellular model was established by treating the cells’ L-NAME and hypoxia. The PE mice model was established by L-NAME administration and was confirmed by the increased systolic blood pressure (SBP) and urinary protein detected. The autophagy and key proteins were detected in human placental tissue, in cells, and in the mice model by Western blot and immunofluorescence staining. Results showed that excessive autophagy could be detected in human PE placental tissue, in the PE cellular model, and in the PE mice model. Hypoxia induces autophagy by activating AMPKα and inhibiting mTOR in vivo and in vitro. Esomeprazole inhibits L‐NAME-induced autophagy in mice by inhibiting AMPKα and activating mTOR. In conclusion, this study demonstrates that the excessive autophagy induced by the SIRT1/AMPKα-mTOR pathway plays a significant role in the pathogenesis of PE. However, esomeprazole treatment inhibits AMPKα but activates mTOR, resulting in the inhibition of autophagy in the placenta and, therefore, mitigates PE symptoms.

Captopril suppresses hepatic mammalian target of rapamycin cell signaling and biomarkers of inflammation and oxidative stress in thioacetamide-induced hepatotoxicity in rats

BACKGROUND

The potential inhibitory effects of captopril, the angiotensin-converting enzyme inhibitor, on thioacetamide (TAA)-induced hepatic mammalian target of rapamycin (mTOR), liver injury enzymes, blood pressure, and biomarkers of inflammation and oxidative stress have not been investigated before.

MATERIALS AND METHODS

Rats were either injected with TAA (200 mg/kg; twice a week for 8 weeks) before being sacrificed after 10 weeks (model group) or were pretreated with captopril (150 mg/kg) daily for two weeks prior to TAA injections and continued receiving both agents until the end of the experiment (protective group).

RESULTS

Captopril significantly (p < .05) inhibited TAA-induced hypertension, liver tissue levels of mTOR, TIMP-1, TNF-α, IL-6, MDA; and blood levels of lipids, ALT, and AST. We further demonstrated a significant (p < .01) positive correlation between mTOR scoring and the levels of inflammatory, oxidative and liver injury biomarkers.

CONCLUSIONS

Captopril protects against TAA-induced mTOR, liver injury enzymes, dyslipidemia, hypertension, inflammation, and oxidative stress.

Smoking for two- effects of tobacco consumption on placenta

Tobacco smoking is an important public health issue recognized by the world health organization as one of the most serious, preventable risk factors for developing a series of pregnancy pathologies. Maternal smoking is positively associated with intrauterine growth restriction (IUGR) and gestational diabetes (GDM), but negatively associated with preeclampsia (PE). In this review, we examine epidemiological, clinical and laboratory studies of smoking effects on immunoregulation during pregnancy, trophoblast function, and placental vasculature development and metabolism. We aim to identify effects of tobacco smoke components on specific placental compartments or cells, which may contribute to the understanding of the influences of maternal smoking on placenta function in normal and pathological pregnancies. Data corroborates that in any trimester, smoking is unsafe for pregnancy and that its detrimental effects outweigh questionable benefits. The effects of maternal smoking on the maternal immune regulation throughout pregnancy and the impact of different tobacco products on fetal growth have not yet been fully understood. Smoking cessation rather than treatment with replacement therapies is recommended for future mothers because also single components of tobacco and its smoke may have detrimental effects on placental function.

Repair Mechanisms of the Neurovascular Unit after Ischemic Stroke with a Focus on VEGF

The functional neural circuits are partially repaired after an ischemic stroke in the central nervous system (CNS). In the CNS, neurovascular units, including neurons, endothelial cells, astrocytes, pericytes, microglia, and oligodendrocytes maintain homeostasis; however, these cellular networks are damaged after an ischemic stroke. The present review discusses the repair potential of stem cells (i.e., mesenchymal stem cells, endothelial precursor cells, and neural stem cells) and gaseous molecules (i.e., nitric oxide and carbon monoxide) with respect to neuroprotection in the acute phase and regeneration in the late phase after an ischemic stroke. Commonly shared molecular mechanisms in the neurovascular unit are associated with the vascular endothelial growth factor (VEGF) and its related factors. Stem cells and gaseous molecules may exert therapeutic effects by diminishing VEGF-mediated vascular leakage and facilitating VEGF-mediated regenerative capacity. This review presents an in-depth discussion of the regeneration ability by which endogenous neural stem cells and endothelial cells produce neurons and vessels capable of replacing injured neurons and vessels in the CNS.

Interferon γ neutralization reduces blood pressure, uterine artery resistance index, and placental oxidative stress in placental ischemic rats

Preeclampsia (PE) is characterized by maternal hypertension, intrauterine growth restriction, and increased cytolytic natural killer cells (cNKs), which secrete interferon γ (IFNγ). However, the precise role of IFNγ in contributing to PE pathophysiology remains unclear. Using the reduced uterine perfusion pressure (RUPP) rat model of placental ischemia, we tested the hypothesis that neutralization of IFNγ in RUPPs will decrease placental reactive oxygen species (ROS) and improve vascular function resulting in decreased MAP and improved fetal growth. On gestation day (GD) 14, the RUPP procedure was performed and on GDs 15 and 18, a subset of normal pregnant rats (NP) and RUPP rats were injected with 10 μg/kg of an anti-rat IFNγ monoclonal antibody. On GD 18, uterine artery resistance index (UARI) was measured via Doppler ultrasound and on GD 19, mean arterial pressure (MAP) was measured, animals were euthanized, and blood and tissues were collected for analysis. Increased MAP was observed in RUPP rats compared with NP and was reduced in RUPP + anti-IFNγ. Placental ROS was also increased in RUPP rats compared with NP rats and was normalized in RUPP + anti-IFNγ. Fetal and placental weights were reduced in RUPP rats, but were not improved following anti-IFNγ treatment. However, UARI was elevated in RUPP compared with NP rats and was reduced in RUPP + anti-IFNγ. In conclusion, we observed that IFNγ neutralization reduced MAP, UARI, and placental ROS in RUPP recipients. These data suggest that IFNγ is a potential mechanism by which cNKs contribute to PE pathophysiology and may represent a therapeutic target to improve maternal outcomes in PE.

Modulation of preeclampsia by the cholinergic anti-inflammatory pathway: Therapeutic perspectives

The cholinergic anti-inflammatory pathway (CAP) is vital for the orchestration of the immune and inflammatory responses under normal and challenged conditions. Over the past two decades, peripheral and central circuits of CAP have been shown to be critically involved in dampening the inflammatory reaction in a wide array of inflammatory disorders. Additionally, emerging evidence supports a key role for CAP in the regulation of the female reproductive system during gestation as well as in the advent of serious pregnancy-related inflammatory insults such as preeclampsia (PE). Within this framework, the modulatory action of CAP encompasses the perinatal maternal and fetal adverse consequences that surface due to antenatal PE programming. Albeit, a considerable gap still exists in our knowledge of the precise cellular and molecular underpinnings of PE/CAP interaction, which hampered global efforts in safeguarding effective preventive or therapeutic measures against PE complications. Here, we summarize reports in the literature regarding the roles of peripheral and reflex cholinergic neuroinflammatory pathways of nicotinic acetylcholine receptors (nAChRs) in reprogramming PE complications in mothers and their progenies. The possible contributions of α7-nAChRs, cholinesterases, immune cells, adhesion molecules, angiogenesis, and endothelial dysfunction to the interaction have also been reviewed.

Fluid shear stress regulates placental growth factor expression via heme oxygenase 1 and iron

Increased fluid shear stress (FSS) is a key initiating stimulus for arteriogenesis, the outward remodeling of collateral arterioles in response to upstream occlusion. Placental growth factor (PLGF) is an important arteriogenic mediator. We previously showed that elevated FSS increases PLGF in a reactive oxygen species (ROS)-dependent fashion both in vitro and ex vivo. Heme oxygenase 1 (HO-1) is a cytoprotective enzyme that is upregulated by stress and has arteriogenic effects. In the current study, we used isolated murine mesentery arterioles and co-cultures of human coronary artery endothelial cells (EC) and smooth muscle cells (SMC) to test the hypothesis that HO-1 mediates the effects of FSS on PLGF. HO-1 mRNA was increased by conditions of increased flow and shear stress in both co-cultures and vessels. Both inhibition of HO-1 with zinc protoporphyrin and HO-1 knockdown abolished the effect of FSS on PLGF. Conversely, induction of HO-1 activity increased PLGF. To determine which HO-1 product upregulates PLGF, co-cultures were treated with a CO donor (CORM-A1), biliverdin, ferric ammonium citrate (FAC), or iron-nitrilotriacetic acid (iron-NTA). Of these FAC and iron-NTA induced an increase PLGF expression. This study demonstrates that FSS acts through iron to induce pro-arteriogenic PLGF, suggesting iron supplementation as a novel potential treatment for revascularization.

Pravastatin Versus Placebo in Pregnancies at High Risk of Term Preeclampsia

BACKGROUND

Effective screening for term preeclampsia is provided by a combination of maternal factors with measurements of mean arterial pressure, serum placental growth factor, and serum soluble fms-like tyrosine kinase-1 at 35 to 37 weeks of gestation, with a detection rate of ≈75% at a screen-positive rate of 10%. However, there is no known intervention to reduce the incidence of the disease.

METHODS

In this multicenter, double-blind, placebo-controlled trial, we randomly assigned 1120 women with singleton pregnancies at high risk of term preeclampsia to receive pravastatin at a dose of 20 mg/d or placebo from 35 to 37 weeks of gestation until delivery or 41 weeks. The primary outcome was delivery with preeclampsia at any time after randomization. The analysis was performed according to intention to treat.

RESULTS

A total of 29 women withdrew consent during the trial. Preeclampsia occurred in 14.6% (80 of 548) of participants in the pravastatin group and in 13.6% (74 of 543) in the placebo group. Allowing for the effect of risk at the time of screening and participating center, the mixed-effects Cox regression showed no evidence of an effect of pravastatin (hazard ratio for statin/placebo, 1.08 [95% CI, 0.78-1.49]; P=0.65). There was no evidence of interaction between the effect of pravastatin, estimated risk of preeclampsia, pregnancy history, adherence, and aspirin treatment. There was no significant between-group difference in the incidence of any secondary outcomes, including gestational hypertension, stillbirth, abruption, delivery of small for gestational age neonates, neonatal death, or neonatal morbidity. There was no significant between-group difference in the treatment effects on serum placental growth factor and soluble fms-like tyrosine kinase-1 concentrations 1 and 3 weeks after randomization. Adherence was good, with reported intake of ≥80% of the required number of tablets in 89% of participants. There were no significant between-group differences in neonatal adverse outcomes or other adverse events.

CONCLUSIONS

Pravastatin in women at high risk of term preeclampsia did not reduce the incidence of delivery with preeclampsia. Registration: URL: https://www.isrctn.com; Unique identifier ISRCTN16123934.

PFOS Inhibited Normal Functional Development of Placenta Cells via PPARγ Signaling

Perfluorooctane sulfonic acid (PFOS), a persistent environmental pollutant, has adverse effects on gestation pregnancy. Peroxisome proliferator-activated receptor γ (PPARγ) is involved in angiogenesis, metabolic processes, anti-inflammatory, and reproductive development. However, the function of PPARγ in PFOS evoked disadvantageous effects on the placenta remain uncertain. Here, we explored the role of PPARγ in PFOS-induced placental toxicity. Cell viability, cell migration, angiogenesis, and mRNA expression were monitored by CCK-8 assay, wound healing assay, tube formation assay, and real-time PCR, respectively. Activation and overexpression of PPARγ were conducted by rosiglitazone or pcDNA-PPARγ, and inhibition and knockdown of PPARγ were performed by GW9662 or si-PPARγ. Results revealed that PFOS decreased cell growth, migration, angiogenesis, and increased inflammation in human HTR-8/SVneo and JEG-3 cells. Placenta diameter and fetal weight decreased in mice treated with PFOS (12.5 mg/kg). In addition, rosiglitazone or pcDNA-PPARγ rescued cell proliferation, migration, angiogenesis, and decreased inflammation induced by PFOS in HTR8/SVneo and JEG-3 cells. Furthermore, GW9662 or si-PPARγ exacerbated the inhibition of cell viability, migration, angiogenesis, and aggravated inflammation induced by PFOS in HTR-8/SVneo and JEG-3 cells. Meanwhile, the results of mRNA expression level were consistent with the cell representation. In conclusion, our findings revealed that PFOS induced placenta cell toxicity and functional damage through PPARγ pathway.

The impact of COVID-19 on pregnancy and therapeutic drug development

Emerging data show that pregnant women with COVID‐19 are at significantly higher risk of severe outcomes compared with non‐pregnant women of similar age. This review discusses the invaluable insight revealed from vaccine clinical trials in women who were vaccinated and inadvertently became pregnant during the trial period. It further explores a number of clinical avenues in their management and proposes a drug development strategy in line with clinical trials for vaccines and drug treatments for the drug development community. Little is known of the long‐term effects of COVID‐19 on the mother and the baby. Our hypothesis that COVID‐19 predisposes pregnant women to pre‐eclampsia or hypertensive disorders during pregnancy is supported by a clinical study, and this may also adversely impact a woman's cardiovascular disease risk later in life. It may also increase a woman's risk of pre‐eclampsia in subsequent pregnancy. This is an ever‐evolving landscape, and early knowledge for healthcare providers and drug innovators is offered to ensure benefits outweigh the risks. COVID‐19 mRNA vaccines appear to generate robust humoral immunity in pregnant and lactating women. This novel approach to vaccination also offers new ways to therapeutically tackle disorders of many unmet medical needs.

Metabolic Control by Heat Stress Determining Cell Fate to Ferroptosis for Effective Cancer Therapy

Flexible manipulation of the fate of cancer cells through exogenous stimulation-induced metabolic reprogramming could handle the cellular plasticity-derived therapies resistance, which provides an effective paradigm for the treatment of refractory and relapsing tumors in clinical settings. Herein, we demonstrated that moderate heat (45 °C) could significantly regress the expression of antioxidants and trigger specific lipid metabolic reprogramming in cancer cells synergized with iron oxide nanoparticles (Fe₃O₄ NPs). This metabolic control behavior destroyed the tumor redox homeostasis and produced overwhelming lipid peroxides, consequently sensitizing the tumor to ferroptosis. Based on these findings, a heat-triggered tumor-specific ferroptosis strategy was proposed by the rational design of a polypeptide-modified and 1H-perfluoropentane (1H-PFP)-encapsulated Fe₃O₄-containing nanoformulation (GBP@Fe₃O₄). When irradiated by an 808 nm laser, the phase transition of 1H-PFP was triggered by localized moderate heat (45 °C), leading to burst release of Fe₃O₄in situ to produce potent reactive oxygen species through the Fenton reaction in the tumor microenvironment. Together with the antioxidant inhibition response and distinctive lipid metabolic reprogramming by heat stress, this oxidative damage was amplified to induce tumor ferroptosis and achieve sufficient antitumor effects. Importantly, we confirmed that ACSBG1, an acyl-CoA synthetase, was the key pro-ferroptotic factor in this heat-induced ferroptosis process. Moreover, knockout of this gene could realize cancer cell death fate conversion from ferroptosis to non-ferroptotic death. This work provides mechanistic insights and practical strategies for heat-triggered ferroptosis in situ to reduce the potential side effects of direct ferroptosis inducers and highlights the key factor in regulating cell fate under heat stress.

Clinical implications of placenta-derived angiogenic/anti-angiogenic biomarkers in pre-eclampsia

Pre-eclampsia (PE) is a devastating systemic disease which results in maternal hypertension with multi-organ failure due to angiogenic imbalance, characterized by lack of circulating pro-angiogenic factors and excess of anti-angiogenic factors. These factors are crucial for understanding the pathophysiology of PE since they serve as a critical link from placental dysfunction to the clinical syndrome of systemic endothelial dysfunction in the disease. Moreover, utilizing these angiogenic/anti-angiogenic biomarkers can be helpful in risk stratifying and the early detection of PE, which allows for timely intervention to improve maternal and neonatal outcomes. In this review, we summarize updated perspectives of the angiogenic imbalance in PE with detailed characterization of key factors involved in the pathogenesis and how the developed biomarkers can be used in clinical settings as diagnostic tools and as possible therapeutic targets of PE.

The Role of B Cells in PE Pathophysiology: A Potential Target for Perinatal Cell-Based Therapy?

The pathophysiology of preeclampsia (PE) is poorly understood; however, there is a large body of evidence that suggests a role of immune cells in the development of PE. Amongst these, B cells are a dominant element in the pathogenesis of PE, and they have been shown to play an important role in various immune-mediated diseases, both as pro-inflammatory and regulatory cells. Perinatal cells are defined as cells from birth-associated tissues isolated from term placentas and fetal annexes and more specifically from the amniotic membrane, chorionic membrane, chorionic villi, umbilical cord (including Wharton's jelly), the basal plate, and the amniotic fluid. They have drawn particular attention in recent years due to their ability to modulate several aspects of immunity, making them promising candidates for the prevention and treatment of various immune-mediated diseases. In this review we describe main findings regarding the multifaceted in vitro and in vivo immunomodulatory properties of perinatal cells, with a focus on B lymphocytes. Indeed, we discuss evidence on the ability of perinatal cells to inhibit B cell proliferation, impair B cell differentiation, and promote regulatory B cell formation. Therefore, the findings discussed herein unveil the possibility to modulate B cell activation and function by exploiting perinatal immunomodulatory properties, thus possibly representing a novel therapeutic strategy in PE.

Melatonin for the Management of Preeclampsia: A Review

Preeclampsia is a disease specific to pregnancy characterised by new-onset hypertension with maternal organ dysfunction and/or fetal growth restriction. It remains a major cause of maternal and perinatal morbidity and mortality. For sixty years, antihypertensives have been the mainstay of treating preeclampsia and only recently have insights into the pathogenesis of the disease opened new avenues for novel therapies. Melatonin is one such option, an endogenous and safe antioxidant, that may improve the maternal condition in preeclampsia while protecting the fetus from a hostile intrauterine environment. Here we review the evidence for melatonin as a possible adjuvant therapy for preeclampsia, including in vitro evidence supporting a role for melatonin in protecting the human placenta, preclinical models, vascular studies, and clinical studies in hypertension and pregnancy.

Heme Oxygenase 1: A Defensive Mediator in Kidney Diseases

The incidence of kidney disease is rising, constituting a significant burden on the healthcare system and making identification of new therapeutic targets increasingly urgent. The heme oxygenase (HO) system performs an important function in the regulation of oxidative stress and inflammation and, via these mechanisms, is thought to play a role in the prevention of non-specific injuries following acute renal failure or resulting from chronic kidney disease. The expression of HO-1 is strongly inducible by a wide range of stimuli in the kidney, consequent to the kidney's filtration role which means HO-1 is exposed to a wide range of endogenous and exogenous molecules, and it has been shown to be protective in a variety of nephropathological animal models. Interestingly, the positive effect of HO-1 occurs in both hemolysis- and rhabdomyolysis-dominated diseases, where the kidney is extensively exposed to heme (a major HO-1 inducer), as well as in non-heme-dependent diseases such as hypertension, diabetic nephropathy or progression to end-stage renal disease. This highlights the complexity of HO-1's functions, which is also illustrated by the fact that, despite the abundance of preclinical data, no drug targeting HO-1 has so far been translated into clinical use. The objective of this review is to assess current knowledge relating HO-1's role in the kidney and its potential interest as a nephroprotection agent. The potential therapeutic openings will be presented, in particular through the identification of clinical trials targeting this enzyme or its products.

Pravastatin suppresses inflammatory cytokines and endothelial activation in patients at risk of developing preeclampsia: INOVASIA study

INTRODUCTION

The Indonesian INOVASIA study is an ongoing multicentre randomized, open controlled trial of pravastatin for the prevention of preeclampsia in patients deemed to be high risk. Here we evaluate the effects of pravastatin on circulating inflammatory and endothelial markers, i.e. Vascular Endothelial Growth Factor (VEGF), Interleukin-6 (IL-6), Endothelin-1 (ET-1), and Nitric Oxide (NO).

METHODS

Pregnant women deemed to be at a high risk of developing preeclampsia women were recruited based on the Fetal Medicine Foundation preeclampsia screening test or a history of preterm preeclampsia, or clinical risk factors in combination with an abnormal uterine artery Doppler flow pattern at 11-20 week's gestation. This is a nested cohort study within the larger trial (INOVASIA); 38 patients were consecutively recruited and assigned to the pravastatin group and the control group. Participants in the pravastatin group received pravastatin (2 × 20 mg p.o) in addition to a standard regimen of aspirin (80 mg p.o) and calcium (1 g p.o), from 14 to 20 weeks until delivery. Blood samples to measure the various biomarkers were obtained in consecutive patients before starting the research medication and just before delivery (pre and post-test examination).

RESULT

The number of samples on the 2 time points for the various biomarkers was: VEGF: 38, IL-6: 30, ET-1: 38, and NO: 35. IL-6 levels decreased significantly in the pravastatin group (mean ± SD): (191.87 ± 82.99 vs. 151.85 + 48.46, p = .013), while levels in the control group did not change significantly (median (interquartile range)) (144.17 (53.91) vs. 140.82 (16.18), p = .177). ET-1 levels decreased significantly in the pravastatin group (3.64 ± 0.85 vs. 3.01 ± 0.74, p = .006) while the control group had more or less stable levels (3.57 ± 1.12 vs. 3.78 ± 0.73 p = .594). NO was the only serum marker that showed significant changes in both groups. NO levels increased in pravastatin group (11.30 (17.43) vs. 41.90 (53.18), p = .044) and decreased in control group (38.70 (34.80) vs. 10.03 (26.96), p = .002). VEGF levels appeared to follow opposite trends in the 2 groups (NS) (Pravastatin: 3.22 (0.62) vs. 3.28 (0.75), p = .402. Control: 3.38 (0.83) vs. 3.06 (0.74), p = .287).

CONCLUSION

Administration of 40 mg pravastatin resulted in an improvement in NO levels, and a decrease in IL-6 and endothelin (ET-1) levels. The direction of the effect of pravastatin on these biomarkers appears to underpin the potential for a beneficial effect of pravastatin in the prevention of preeclampsia.

Pravastatin Promotes Endothelial Colony-Forming Cell Function, Angiogenic Signaling and Protein Expression In Vitro

Endothelial dysfunction is a primary feature of several cardiovascular diseases. Endothelial colony-forming cells (ECFCs) represent a highly proliferative subtype of endothelial progenitor cells (EPCs), which are involved in neovascularization and vascular repair. Statins are known to improve the outcome of cardiovascular diseases via pleiotropic effects. We hypothesized that treatment with the 3-hydroxy-3-methyl-glutaryl–coenzyme A (HMG-CoA) reductase inhibitor pravastatin increases ECFCs’ functional capacities and regulates the expression of proteins which modulate endothelial health in a favourable manner. Umbilical cord blood derived ECFCs were incubated with different concentrations of pravastatin with or without mevalonate, a key intermediate in cholesterol synthesis. Functional capacities such as migration, proliferation and tube formation were addressed in corresponding in vitro assays. mRNA and protein levels or phosphorylation of protein kinase B (AKT), endothelial nitric oxide synthase (eNOS), heme oxygenase-1 (HO-1), vascular endothelial growth factor A (VEGF-A), placental growth factor (PlGF), soluble fms-like tyrosine kinase-1 (sFlt-1) and endoglin (Eng) were analyzed by real time PCR or immunoblot, respectively. Proliferation, migration and tube formation of ECFCs were enhanced after pravastatin treatment, and AKT- and eNOS-phosphorylation were augmented. Further, expression levels of HO-1, VEGF-A and PlGF were increased, whereas expression levels of sFlt-1 and Eng were decreased. Pravastatin induced effects were reversible by the addition of mevalonate. Pravastatin induces beneficial effects on ECFC function, angiogenic signaling and protein expression. These effects may contribute to understand the pleiotropic function of statins as well as to provide a promising option to improve ECFCs’ condition in cell therapy in order to ameliorate endothelial dysfunction.

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.

Haem oxygenases play a pivotal role in placental physiology and pathology

BACKGROUND

Haem oxygenases (HO) catabolise haem, which is the prosthetic group of numerous haemoproteins. Thus, multiple primary cellular pathways and functions rely on haem availability. HO exists in two isoforms, both expressed in the placenta, namely HO-1 and HO-2, the first being inducible. Haem oxygenases, particularly HO-1, have garnered specific interest in the field of physiological and pathological placental function. These enzymes mediate haem degradation by cleaving the alpha methene bridge to produce biliverdin, which is subsequently converted to bilirubin, carbon monoxide and iron. HO-1 has anti-inflammatory and antioxidant activities.

SEARCH METHODS

An initial literature analysis was performed using PubMed on 3 October 2018 using key terms such as 'haem oxygenase and pregnancy', 'haem oxygenase and placenta', 'HO-1 and pregnancy', 'HO-1 and placenta', 'HO and placenta', 'HO and pregnancy', 'genetic variant and HO', 'CO and pregnancy', 'CO and placenta', 'Bilirubin and pregnancy', 'Iron and pregnancy' and 'PPAR and Haem', selecting consensus conferences, recommendations, meta-analyses, practical recommendations and reviews. A second literature analysis was performed, including notable miscarriages, foetal loss and diabetes mellitus, on 20 December 2019. The three authors studied the publications independently to decipher whether they should be included in the manuscript.

OBJECTIVE AND RATIONALE

This review aimed to summarise current pieces of knowledge of haem oxygenase location, function and regulation in the placenta, either in healthy pregnancies or those associated with miscarriages and foetal loss, pre-eclampsia, foetal growth restriction and diabetes mellitus.

OUTCOMES

HO-1 exerts some protective effects on the placentation, probably by a combination of factors, including its interrelation with the PGC-1α/PPAR pathway and the sFlt1/PlGF balance, and through its primary metabolites, notably carbon monoxide and bilirubin. Its protective role has been highlighted in numerous pregnancy conditions, including pre-eclampsia, foetal growth restriction, gestational diabetes mellitus and miscarriages.

WIDER IMPLICATIONS

HO-1 is a crucial enzyme in physiological and pathological placentation. This protective enzyme is currently considered a potential therapeutic target in various pregnancy diseases.

Hydrogen sulfide releasing molecule MZe786 inhibits soluble Flt-1 and prevents preeclampsia in a refined RUPP mouse model

An imbalance in angiogenic growth factors and poor utero-placental perfusion are strongly associated with preeclampsia. The reduced utero-placental perfusion (RUPP) model that mimics insufficient placental perfusion is used to study preeclampsia. The aim of this study was to develop a refined RUPP model in C57Bl/6 J mice to test the efficacy of MZe786 as a potential inhibitor of soluble Flt-1 for preeclampsia therapy. Murine RUPP (mRUPP) was induced through bilateral ligation of the ovarian arteries at E11.5 that resulted in typical preeclampsia symptoms including increase in mean arterial pressure (MAP), kidney injury and elevated soluble Flt-1 (sFlt-1) levels in the maternal plasma and amniotic fluid. The murine RUPP kidneys showed tubular and glomerular damage along with increased oxidative stress characterised by increased nitrotyrosine staining. The mRUPP displayed abnormal placental vascular histology, reduced expression of placental cystathionine γ-lyase (CSE), the hydrogen sulfide (H₂S) producing enzyme, and resulted in adverse fetal outcomes (FGR). Importantly, oral administration of hydrogen sulfide (H₂S)-releasing compound MZe786 from E11.5 to E17.5 successfully prevented the development of preeclampsia. Specifically, MZe786 treatment reduced maternal MAP and kidney nitrotyrosine staining and improved fetal outcome. The circulation levels of sFlt-1 were dramatically decreased in MZe786 treated animals implying that H₂S released from MZe786 offered protection by inhibiting sFlt-1 levels. MZe786 prevent preeclampsia and warrant a rapid move to randomised control clinical trial.

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Refined mouse reduced uterine perfusion pressure (mRUPP) model exhibits preeclampsia symptoms.

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Mouse RUPP induces maternal hypertension, kidney injury, elevates circulating sFlt-1 levels and promotes nitrosative stress.

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Mouse RUPP reduces expression of the protective enzyme, placental cystathionine γ-lyase and causes poor fetal outcome.

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H₂S releasing aspirin, MZe786, acts as an inhibitor of sFlt-1 to successfully prevent preeclampsia and improve fetal outcome.

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MZe786 is a novel drug with therapeutic potential to prevent preeclampsia.

MZe786, a hydrogen sulfide-releasing aspirin prevents preeclampsia in heme oxygenase-1 haplodeficient pregnancy under high soluble flt-1 environment

Preeclampsia affects one in twelve of the 130 million pregnancies a year. The lack of an effective therapeutic to prevent or treat it is responsible for an annual global cost burden of 100 billion US dollars. Preeclampsia also affects these women later in life as it is a recognised risk factor for cardiovascular disease, stroke and vascular dementia. Our laboratory demonstrated that preeclampsia is associated with high soluble fms-like tyrosine kinase 1 (sFlt-1) and low heme oxygenase-1 (HO1/Hmox1) expression. Here we sought to determine the therapeutic value of a novel H₂S-releasing aspirin (MZe786) in HO-1 haploid deficient (Hmox1^+/−) pregnant mice in a high sFlt-1 environment. Pregnant Hmox1^+/− mice were injected with adenovirus encoding sFlt-1 or control virus at gestation day E11.5. Subsequently, Hmox1^+/− dams were treated daily with a number of treatment regimens until E17.5, when maternal and fetal outcomes were assessed. Here we show that HO-1 compromised mice in a high sFlt-1 environment during pregnancy exhibit severe preeclampsia signs and a reduction in antioxidant genes. MZe786 ameliorates preeclampsia by reducing hypertension and renal damage possibly by stimulating antioxidant genes. MZe786 also improved fetal outcome in comparison with aspirin alone and appears to be a better therapeutic agent at preventing preeclampsia than aspirin alone.

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Partial loss of heme oxygenase-1 under high soluble Flt-1 causes severe preeclampsia compared to high sFlt-1 alone.

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MZe786, hydrogen sulfide releasing aspirin prevents preeclampsia by suppressing maternal hypertension and kidney injury.

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MZe786 is able to rescue pregnancy and improves fetal outcome despite the persistent high levels of sFlt-1.

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MZe786 is a superior therapeutic candidate than aspirin in preventing preeclampsia.

Dysregulation of hypoxia-inducible factor-1α (Hif1α) expression in the Hmox1-deficient placenta

Introduction

Severe hypoxia exists in placentas during early pregnancy, with reoxygenation during mid-gestation. Hypoxia-inducible factor-1α (Hif1α), an oxygen sensor, initiates placental vascular development. We have shown that the placental vasculature in Hmox1-deficient (Hmox1^+/−, Het) pregnancies is impaired, with morphological defects similar to Hif1α-deficient placentas.

Materials and methods

Whole wild-type (WT) and Het mouse placentas were collected at E8.5 (1%–3% O₂) and E9.5–15.5 (8%–10% O₂). mRNA levels were determined using real-time RT-PCR or PCR arrays and protein levels using Western blot. Bone marrow-derived macrophages (BMDMs) from WT, Het, and Hmox1 knockout (KO) mice, representing different Hmox1 cellular levels, were generated to study the role of Hmox1 on Hif1α ′s response to hypoxia-reoxygenation and gestational age-specific placental lysates.

Results

Hif1α was expressed in WT and Het placentas throughout gestation, with protein levels peaking at E8.5 and mRNA levels significantly upregulated from E9.5–E13.5, but significantly lower in Het placentas. Genes associated with angiogenesis (Vegfa, Vegfr1, Mmp2, Cxcl12, Angpt1, Nos3), antioxidants (Sod1, Gpx1), and transcription factors (Ap2, Bach1, Nrf2) were significantly different in Het placentas. In response to in vitro hypoxia-reoxygenation and to WT or Het placental lysates, Hif1α transcription was lower in Het and Hmox1 KO BMDMs compared with WT BMDMs.

Discussion

These findings suggest that deficiencies in Hmox1 underlie the insufficient placental Hif1α response to hypoxia-reoxygenation during gestation and subsequently impair downstream placental vascular formation. Therefore, a dysregulation of Hif1α expression caused by any genetic defect or environmental influence in early pregnancy could be the root cause of pregnancy disorders.

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Expression of Hif1α in wild-type (WT) placentas is gestational age-dependent.

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Hif1α expression is reduced in Hmox1-deficient placentas.

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Expression of angiogenic genes is altered in Hmox1-deficient placentas.

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Hypoxia-reoxygenation induces a differential expression of Hif1α in cells.

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Adding placental lysates dysregulates expression of Hif1α in Hmox1-deficient cells.

Heme oxygenase-1 gene modified human placental mesenchymal stem cells promote placental angiogenesis and spiral artery remodeling by improving the balance of angiogenic factors in vitro

INTRODUCTION

Abnormal placental vascular development is a possible cause of preeclampsia. Mesenchymal stem cell (MSC)-based therapy is a promising approach for tissue repair and angiogenesis. Further, heme oxygenase-1 (HO-1) has beneficial effects on the angiogenic balance during pregnancy. We explored the effects of HO-1 overexpression on placental vascularization using human placenta-derived MSCs (hPMSCs).

METHODS

hPMSCs were isolated from term placenta, and the HO-1 gene was transfected with a lentivirus. Proliferation, migration, and apoptosis of hPMSCs and HO-hPMSCs were examined using CCK8 assay, trans-well assay, and flow cytometry, respectively. Paracrine secretion of the angiogenesis factors VEGF and PlGF, as well as the anti-angiogenesis factors sFlt-1 and sEng, from hPMSC/HO-hPMSCs was measured by qRT-PCR and ELISA. Human umbilical cord endothelial cells and a villus-decidua co-culture were treated with conditioned media to study the effect of HO-1-hPMSCs on tube formation and villus vascular remodeling.

RESULTS

HO-1 significantly improved the proliferation and migration of hPMSCs. Additionally, HO-1 reduced hPMSCs apoptosis. The levels of VEGF were increased in HO-1-hPMSCs, whereas those of sFlt-1 decreased. Tube formation assays showed that the conditioned media from HO-1-hPMSCs resulted in more branching points than those from the controls. The villus-decidua co-culture system confirmed that HO-1-hPMSCs are conducive to angiogenesis and vascular remodeling.

DISCUSSION

HO-1-modified hPMSCs improve placental vascularization by promoting a balance of pro- and anti- angiogenesis factors, which is worthy of further study as an alternative treatment for preeclampsia.

MZe786 Rescues Cardiac Mitochondrial Activity in High sFlt-1 and Low HO-1 Environment

Hypertensive disorder in pregnancy is a major cause of maternal and perinatal mortality worldwide. Women who have had preeclampsia are at three to four times higher risk in later life of developing high blood pressure and heart disease. Soluble Flt-1 (sFlt-1) is elevated in preeclampsia and may remain high postpartum in women with a history of preeclampsia. Heme oxygenase-1 (Hmox1/HO-1) exerts protective effects against oxidative stimuli and is compromised in the placenta of pregnant women with preeclampsia. We hypothesized that sFlt-1 inhibits cardiac mitochondrial activity in HO-1 deficient mice. HO-1 haplo-insufficient mice (Hmox1^+/−) were injected with adenovirus encoding sFlt-1 (Ad-sFlt-1) or control virus (Ad-CMV). Subsequently, they were treated daily with either placebo or MZe786 for six days, when the heart tissue was harvested to assess cardiac mitochondrial activity. Here, we show that the loss of HO-1 disturbed cardiac mitochondrial respiration and reduced mitochondrial biogenesis. The overexpression of sFlt-1 resulted in the inhibition of the cardiac mitochondrial activity in Hmox1^+/− mice. The present study demonstrates that the hydrogen sulfide (H₂S) releasing molecule, MZe786, rescues mitochondrial activity by stimulating cardiac mitochondrial biogenesis and antioxidant defense in Hmox1^−/− mice and in Hmox1^+/− mice exposed to a high sFlt-1 environment.