Oxidative stress in early pregnancy and the risk of preeclampsia

Metabolic theory of preeclampsia: implications for maternal cardiovascular health

Preeclampsia (PE) is a multisystemic disorder of pregnancy that not only causes perinatal mortality and morbidity but also has a long-term toll on the maternal and fetal cardiovascular system. Women diagnosed with PE are at greater risk for the subsequent development of hypertension, ischemic heart disease, cardiomyopathy, cerebral edema, seizures, and end-stage renal disease. Although PE is considered heterogeneous, inefficient extravillous trophoblast (EVT) migration leading to deficient spiral artery remodeling and increased uteroplacental vascular resistance is the likely initiation of the disease. The principal pathophysiology is placental hypoxia, causing subsequent oxidative stress, leading to mitochondrial dysfunction, mitophagy, and immunological imbalance. The damage imposed on the placenta in turn results in the "stress response" categorized by the dysfunctional release of vasoactive components including oxidative stressors, proinflammatory factors, and cytokines into the maternal circulation. These bioactive factors have deleterious effects on systemic endothelial cells and coagulation leading to generalized vascular dysfunction and hypercoagulability. A better understanding of these metabolic factors may lead to novel therapeutic approaches to prevent and treat this multisystemic disorder. In this review, we connect the hypoxic-oxidative stress and inflammation involved in the pathophysiology of PE to the resulting persistent cardiovascular complications in patients with preeclampsia.

Oxidative stress biomarkers in pregnancy: a systematic review

BACKGROUND

This systematic review explores the level of oxidative stress (OS) markers during pregnancy and their correlation with complications. Unlike previous studies, it refrains from directly investigating the role of OS but instead synthesises data on the levels of these markers and their implications for various pregnancy-related complications such as preeclampsia, intrauterine growth restrictions, preterm premature rupture of membranes, preterm labour, gestational diabetes mellitus and miscarriages.

METHOD

STUDY DESIGN: Utilizing a systematic review approach, we conducted a comprehensive search across databases, including MEDLINE, CINAHL (EBSCOhost), ScienceDirect, Web of Science, and SCOPUS. Our search encompassed all publication years in English.

RESULTS

After evaluating 54,173 records, 45 studies with a low risk of bias were selected for inclusion. This systematic review has underscored the importance of these markers in both physiological and pathological pregnancy states such as preeclampsia, intrauterine growth restrictions, preterm premature rupture of membranes, preterm labour, gestational diabetes mellitus and miscarriages.

CONCLUSION

This systematic review provides valuable insights into the role of OS in pregnancy and their connection to complications. These selected studies delved deeply into OS markers during pregnancy and their implications for associated complications. The comprehensive findings highlighted the significance of OS markers in both normal and pathological pregnancy conditions, paving the way for further research in this field.

Variants and Haplotypes of SIRT1 (rs7895833, rs7069102, and rs2273773) are Associated with the Risk of Preeclampsia and Affect the Trace Elements and Antioxidant Enzymes Levels

Preeclampsia is the most common and serious complication of pregnancy. Variants of Sirtuin-1 (SIRT1) as a key player in the regulation of oxidant/antioxidant signaling pathways might be involved in the pathogenesis of preeclampsia. In the present case-control study 300 women with and without preeclampsia were studied for SIRT1 variants (rs7895833, rs7069102, and rs2273773) and haplotypes. Also, the relationship of glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities and Zn, Cu, and Se levels to the polymorphisms were investigated. The SIRT1 rs7895833 A > G, rs7069102 C > G, and the rs2273773 C > T polymorphisms were associated with the risk of preeclampsia. We found the haplotypes G (rs7895833) C (rs7069102) C (rs2273773), GCC, and ACC compared to the AGT decreased the risk of preeclampsia. The risk haplotype of AGT was associated with higher GPx activity compared to the GCC haplotype. A significantly higher level of Cu and lower levels of Zn and Se in patients with preeclampsia compared to controls were detected. Also, a significantly lower SOD and higher GPx activity in preeclamptic patients compared to controls were found. The three risk genotypes of AA (rs7895833), GG (rs7069102), and TT (rs2273773) significantly decreased the Zn level and SOD activity, and the TT genotype (rs2273773) increased the Cu level in all studied women. The presence of rs7069102 polymorphism was associated with enhanced systolic blood pressure. For the first time, we indicated three SIRT1 polymorphisms and the AGT haplotype are risk factors for preeclampsia development. Also, SIRT1 variants and haplotypes affect the levels of antioxidant enzymes and their cofactors, complicating the pregnancy outcome.

The significance of mitochondrial haplogroups in preeclampsia risk

OBJECTIVE

To determine whether mitochondrial haplogroups function as disease-modifiers or as susceptibility factors in preeclampsia using a traditional haplogroup association model.

METHODS

This retrospective study haplotyped 235 control and 78 preeclamptic pregnancies from Denmark using either real-time PCR or Sanger sequencing depending on the rarity of the haplogroup.

RESULTS

No significant association between haplogroups and the risk of preeclampsia was found, nor was any role for haplogroups in disease severity uncovered.

CONCLUSION

Mitochondrial haplogroups are not associated with preeclampsia or the severity of preeclampsia in the Danish population. However, this study cannot exclude a role for less common mtDNA variation. Models that can examine these should be applied in preeclamptic patients.

The Gestational Pathologies Effect on the Human Milk Redox Homeostasis: A First Step towards Its Definition

BACKGROUND

Human Milk (HM) is a dynamic nourishment; its composition is influenced by several conditions such as gestational age, maternal diet and ethnicity. It appears important to evaluate the impact that gestational pathologies have on HM components and if their presence, as a source of oxidative stress in the mother, influence milk's redox homeostasis. To assess the effect of Preeclampsia (PE) and Gestational Diabetes Mellitus (GDM) on some aspects of human milk redox homeostasis, we chose to investigate both oxidative and antioxidant aspects, with, respectively, Lipid hydroperoxides (LOOHs) and Glutathione (GSH).

METHODS

Women with PE, GDM and who were healthy were recruited for this study. Colostrum, transitional and mature milk samples were collected. GSH and LOOHs levels were measured using a spectrophotometric test. To investigate the effect of pathology on redox homeostasis, a mixed linear model with unistructural covariance structure was performed.

RESULTS

A total of 120 mothers were recruited. The GSH concentration results were significantly lower in GDM women than in healthy women only in colostrum (p < 0.01). No other differences emerged. LOOHs was not detectable in almost all the samples.

DISCUSSION

Our study is the first to extensively evaluate these components in the HM of women with these gestational pathologies. The main observation is that GDM can alter the GSH level of HM, mainly in colostrum.

OX40 (CD134) Expression on T Regulatory Cells Is Related to Serious Hypertensive Disorders in Pregnancy

Hypertension is one of the leading causes of morbidity and mortality among women related to pregnancy, childbirth and the postpartum period. The pathogenesis of gestational hypertension is complex and still not fully understood. The aim of this study was to assess the population of circulating CD4+CD25+FoxP3+ cells and its differentiation in terms of OX40 expression in two forms of hypertension: isolated hypertension developing after the 20th week of pregnancy and pre-eclampsia. The study included a group of 60 patients with hypertension and 48 healthy controls. The analysis of the percentage of Tregs was performed by flow cytometry. There was no difference in the percentage of peripheral lymphocytes between the groups. In the group of women with preeclampsia compared to the group with gestational hypertension, significantly higher percentages of CD4+CD25+FoxP3+ cells (p = 0.03) and percentages of CD4+CD25+FoxP3+ cells expressing the OX40 antigen (p = 0.001) were observed. OX40 expression on Tregs seems to be related to more serious type of hypertensive disorders in pregnant women.

MiR-218-5p promotes trophoblast infiltration and inhibits endoplasmic reticulum/oxidative stress by reducing UBE3A-mediated degradation of SATB1

This research evaluated the effects of miR-218-5p on trophoblast infiltration and endoplasmic reticulum/oxidative stress during preeclampsia (PE). The expression of miR-218-5p and special AT-rich sequence binding protein 1 (SATB1) in placental tissues from 25 patients with PE and 25 normal pregnant subjects was determined using qRT-PCR and western blotting. Cell invasion and cell migration were detected by performing Transwell assays and scratch assays, respectively. MMP-2/9, TIMP1/2, HIF-1α, p-eIF2α, and ATF4 expression in cells was assessed through western blotting. Intracellular reactive oxygen species were detected using 2,7-dichlorodihydrofluorescein diacetate, and intracellular malondialdehyde and superoxide dismutase activities were determined with kits. Dual-luciferase and RNA pull-down assays were performed to verify the interaction between miR-218-5p and UBE3A. Co-immunoprecipitation and western blotting were used to detect the ubiquitination levels of SATB1. A rat model of PE was established, and an miR-218-5p agomir was injected into rat placental tissues. The pathological characteristics of placental tissues were detected via HE staining, and MMP-2/9, TIMP1/2, p-eIF2α, and ATF4 expression in rat placental tissues was determined through western blotting. MiR-218-5p and SATB1 were expressed at low levels, while UBE3A was highly expressed in the placental tissues of patients with PE. The transfection of an miR-218-5p mimic, UBE3A shRNA, or an SATB1 overexpression vector into HTR-8/SVneo cells promoted trophoblast infiltration and inhibited endoplasmic reticulum/oxidative stress. It was determined that UBE3A is a target of miR-218-5p; UBE3A induces ubiquitin-mediated degradation of SATB1. In PE model rats, miR-218-5p alleviated pathological features, promoted trophoblast infiltration, and inhibited endoplasmic reticulum/oxidative stress. MiR-218-5p targeted and negatively regulated UBE3A expression to inhibit ubiquitin-mediated SATB1 degradation, promote trophoblast infiltration, and inhibit endoplasmic reticulum/oxidative stress.

Nigericin Abrogates Maternal and Embryonic Oxidative Stress in the Streptozotocin-Induced Diabetic Pregnant Rats

Hyperglycemic exposure in diabetic pregnancy can lead to many developmental changes, such as delayed development, fetal malformations, and fetal/embryo death. These detrimental complications are collectively known as diabetic embryopathy or teratogenesis. The current study focuses to discover the therapeutic properties of the nigericin against the STZ-stimulated diabetic embryopathy via alleviation of maternal and embryonic oxidative stress. The male and female rats at a 1:1 ratio were permitted to mate overnight to establish the course of pregnancy. The pregnant rats were distributed into four groups control, diabetic pregnant (via administering 40 mg/kg of STZ), and diabetic + 10 and 20 mg/kg of nigericin-administered (via oral gavage from days 5 to 12) groups, respectively. The glucose level, urine output, diet intake, and body weight were determined carefully. The embryo and placenta weight and implantation rates were examined, and data were tabulated. The total protein and lipid profiles were assessed using respective kits. The oxidative stress markers and antioxidant enzymes were examined using respective assay kits. The 10 and 20 mg/kg of nigericin treatment decreased the glucose level and urine output and improved the diet intake and body weight gain in diabetic pregnant rats. The nigericin also decreased the total protein, cholesterol, triglycerides, and very-low-density lipoprotein (VLDL) and improved the high-density lipoprotein (HDL) in the serum of pregnant rats. The levels of malondialdehyde (MDA), reactive oxygen species (ROS), and protein carbonyls were decreased by the nigericin in both liver and embryos of the pregnant rats. The levels of glutathione (GSH), total thiols, and activities of catalase (CAT), glutathione reductase (GR), superoxide dismutase (SOD), glutathione peroxidase (GPX), and glutathione S-transferase (GST) were improved by the nigericin in the diabetic pregnant rats. Altogether, these results provide evidence that nigericin treatment remarkably attenuates the diabetes-stimulated embryopathy in rats. The nigericin effectively decreased embryo lethality, reduced glucose and dyslipidemia, and relieves oxidative stress via upregulating the antioxidant enzyme activities. Hence, it can be a talented therapeutic agent to treat diabetic pregnancy-associated complications.

Interrelation between miRNAs Expression Associated with Redox State Fluctuations, Immune and Inflammatory Response Activation, and Neonatal Outcomes in Complicated Pregnancy, Accompanied by Placental Insufficiency

Redox disbalance in placental cells leads to the hyperproduction of reactive oxygen species (ROS), it mediates the dysregulation of the maternal immune tolerance to a semi-allogenic fetus, inducing pro-inflammatory reactions, and it plays a central role in perinatal complications and neonatal disease programming. Microvesicles, which provide transplacental communication between a mother and fetus, contain microRNAs (miRNAs) that are sensitive to oxidative stress (OS) mediators and can control the balance of ROS production and utilization in target cells. In the context of this paradigm, we evaluated the markers of redox balance—MDA and 4-HNE for OS and GPx, and SOD, CAT, and GSH for the antioxidant system in the cord blood plasma of newborns diagnosed with fetal growth restriction (FGR)—by using polarography, spectrophotometry, and Western blotting. The expression of miRNAs associated with OS, immune and inflammatory responses in the blood plasma of newborns with intrauterine pneumonia (IP), neonatal sepsis (NS) and respiratory distress syndrome (RDS) was evaluated by a quantitative RT-PCR. Significant differences in the MDA level and reduced GPx and CAT activity were co-found for early-onset FGR (i.e., <34 gestational age). Significant correlations were found with a low birth weight by Apgar scores with reduced levels of antioxidant enzymes. Indeed, the level of OS markers increased in early-onset FGR in newborns with an extremely low body weight and high echogenicity of the periventricular zones, and reduced in late-onset FGR in newborns with IP, hyperbilirubinemia, intraventricular hemorrhage (IVH) and cerebral cysts. A prognostic model (AUC = 1; cutoff—0.5) was developed to assess the risk of IVH in newborns diagnosed with FGR based on the assessment of the OS markers (i.e., MDA + 4 HNE + CAT + GSH). A significant increase in the miR-127-3p expression was found in the plasma of newborns with NS (<32 GA; p ≤ 0.03 and >32 GA; p ≤ 0.009), IP (>32 GA; p ≤ 0.0001), and RDS (>32 GA; p ≤ 0.03). At the same time, the expression of miR-25-3p (p ≤ 0.03) was increased only in newborns with NS (>32 GA; p ≤ 0.03). The risk of developing IVH for premature newborns with IP (AUC = 0.8; cutoff—0.6) and NS (AUC = 0.68; cutoff—0.49) was assessed based on the miR-25-3p and miR-127-3p expression. Several key transcription factors were identified as the targets of studied miRNA since they are involved in the regulation of OS (NRF2), signaling and activation of the immune response (PRDM1, CCL26) and, also, inflammatory responses (NFKB1). The study of these miRNAs showed that they are involved in the modulation of processes leading to perinatal complications. Moreover, miR-127-3p is related to pro-inflammatory reactions and the formation of the macrophage phenotype in newborns with IP, NS, and RDS, while miR-25-3p is associated with an inhibition of macrophage migration and activation of antioxidant enzymes, which may prevent the development of oxidative damage in newborns with NS.

Markers of Oxidative Stress in Obstetrics and Gynaecology-A Systematic Literature Review

Oxidative stress has been implicated in many diseases, including reproductive and pregnancy disorders, from subfertility to maternal vascular disease or preterm labour. There is, however, discrepancy within the standardized markers of oxidative stress in obstetrics and gynaecology in clinical studies. This review aims to present the scope of markers used between 2012 and 2022 to describe oxidative stress with regard to reproduction, pregnancy, and pregnancy-related issues. Despite the abundance of evidence, there is no consensus on the set of standardised markers of oxidative stress which poses a challenge to achieve universal consensus in order to appropriately triangulate the results.

Integrated Metabolomic and Lipidomic Analysis in the Placenta of Preeclampsia

Preeclampsia is one of the most common severe pregnancy complications in obstetrics, which is considered a placental source disease. However, the mechanisms underlying preeclampsia remain largely unknown. In this study, UPLC-MS/MS-based metabolomic and lipidomic analysis was used to explore the characteristic placental metabolites in preeclampsia. The results revealed that there were significant changes in metabolites between preeclampsia and normotensive placentas. Weighted correlation network analysis (WGCNA) identified the correlation network module of metabolites highly related to preeclampsia and the clinical traits reflecting disease severity. The metabolic perturbations were primarily associated with glycerophospholipid and glutathione metabolism, which might influent membrane structures of organisms and mitochondria function. Using linear models, three metabolites had an area under receiver operating characteristic curves (AUROC) ≥ 0.80 and three lipids had an AUROC ≥ 0.90. Therefore, metabolomics and lipidomics may offer a novel insight for a better understanding of preeclampsia and provide a useful molecular mechanism underlying preeclampsia.

Association of prenatal modifiable risk factors with attention-deficit hyperactivity disorder outcomes at age 10 and 15 in an extremely low gestational age cohort

Background

The increased risk of developing attention-deficit hyperactivity disorder (ADHD) in extremely preterm infants is well-documented. Better understanding of perinatal risk factors, particularly those that are modifiable, can inform prevention efforts.

Methods

We examined data from the Extremely Low Gestational Age Newborns (ELGAN) Study. Participants were screened for ADHD at age 10 with the Child Symptom Inventory-4 (N = 734) and assessed at age 15 with a structured diagnostic interview (MINI-KID) to evaluate for the diagnosis of ADHD (N = 575). We studied associations of pre-pregnancy maternal body mass index (BMI), pregestational and/or gestational diabetes, maternal smoking during pregnancy (MSDP), and hypertensive disorders of pregnancy (HDP) with 10-year and 15-year ADHD outcomes. Relative risks were calculated using Poisson regression models with robust error variance, adjusted for maternal age, maternal educational status, use of food stamps, public insurance status, marital status at birth, and family history of ADHD. We defined ADHD as a positive screen on the CSI-4 at age 10 and/or meeting DSM-5 criteria at age 15 on the MINI-KID. We evaluated the robustness of the associations to broadening or restricting the definition of ADHD. We limited the analysis to individuals with IQ ≥ 70 to decrease confounding by cognitive functioning. We evaluated interactions between maternal BMI and diabetes status. We assessed for mediation of risk increase by alterations in inflammatory or neurotrophic protein levels in the first week of life.

Results

Elevated maternal BMI and maternal diabetes were each associated with a 55-65% increase in risk of ADHD, with evidence of both additive and multiplicative interactions between the two exposures. MSDP and HDP were not associated with the risk of ADHD outcomes. There was some evidence for association of ADHD outcomes with high levels of inflammatory proteins or moderate levels of neurotrophic proteins, but there was no evidence that these mediated the risk associated with maternal BMI or diabetes.

Conclusion

Contrary to previous population-based studies, MSDP and HDP did not predict ADHD outcomes in this extremely preterm cohort, but elevated maternal pre-pregnancy BMI, maternal diabetes, and perinatal inflammatory markers were associated with increased risk of ADHD at age 10 and/or 15, with positive interaction between pre-pregnancy BMI and maternal diabetes.

Nrf2 rs6721961 and Oxidative Stress in Preeclampsia: Association with the Risk of Preeclampsia and Early-Onset Preeclampsia

Preeclampsia as a multifactor hypertensive disorder of pregnancy is associated with enhanced placental oxidative stress. The Keap1-Nrf2 pathway protects cells against oxidative stress. We examined the possible association between the Nrf2 variants in relation to oxidative stress parameters with the risk of preeclampsia. We studied 150 preeclampsia women and 150 women with a normal pregnancy to find the frequency of Nrf2 rs6721961 genotypes using the PCR-RFLP method. Also, an association between the Nrf2 genotypes with the levels of malondialdehyde (MDA) and total antioxidant capacity (TAC) was analyzed. Significantly lower TAC and higher MDA levels were found in preeclampsia patients compared to controls (P<0.0001). For the first time, we report an association between the Nrf2 rs6721961 polymorphism and preeclampsia risk. The present study indicated that the GT genotype and the T allele of the Nrf2 rs6721961 increased the risk of preeclampsia by 2.81 and 2.39 times, respectively. Also, the Nrf2 TT genotype was associated with a 3.9-fold increased risk of early-onset preeclampsia. We detected a positive association between the levels of body mass index, MDA, and the Nrf2 polymorphism with the risk of preeclampsia and a negative correlation between the level of TAC with the preeclampsia risk. Also, an association between the rs6721961 TT genotype with higher serum MDA levels was found. Our study suggests oxidative stress is involved in the pathogenesis of preeclampsia and the Nrf2 rs6721961 polymorphism through alteration in the levels of oxidative stress parameters might increase the risk of preeclampsia and early-onset preeclampsia.

Combined apocyanin and aspirin treatment activates the PI3K/Nrf2/HO-1 signaling pathway and ameliorates preeclampsia symptoms in rats

OBJECTIVE

Pre-eclampsia (PE) is a pregnancy-associated disease characterized by placental dysfunction and increased oxidative stress. Apocyanin is a potent antioxidant and anti-inflammatory which has shown beneficial effects on PE pathogenesis. Aspirin is recognized as the recommendable drug in PE prevention and therapy. Therefore, we aimed to investigate the effects of combining apocyanin and aspirin to treat PE on rat models induced by N-nitro-L-arginine methyl ester (L-NAME) from gestational day (GD) 6 to 16 and elucidate the potential mechanisms.

METHODS

First, female pregnant rats were divided into five different groups: pregnant control, PE, PE + apocyanin, PE + aspirin, and PE + apocyanin + aspirin. Animals received apocyanin (16 mg/kg/day) orally or aspirin by gavage (1.5 mg/kg BM/day) from GD 4 to 16. Blood pressure and urine protein content were monitored every 4 days.

RESULTS

In the PE rat model, elevated systolic blood pressure and proteinuria were ameliorated by the combination of apocyanin and aspirin. Meanwhile, compared with single-dose apocyanin or aspirin, the combined treatment significantly corrected abnormal pregnancy outcomes, decreased sFlt-1 and PlGF, and alleviated oxidative stress both in blood and placental tissues. Moreover, the combined treatment upregulated PI3K, Akt, Nrf2, and HO-1 protein levels in the placental tissues from PE rats.Conclusion: Overall, our results suggested that combined treatment of apocyanin and aspirin ameliorates the PE symptoms compared with single-dose apocyanin or aspirin in a PE rat model. Also, we demonstrated that activating the PI3K/Nrf2/HO-1 pathway can be a valuable therapeutic target to improve the pregnancy outcomes of PE.

Biomarkers of Inflammation and Redox Imbalance in Umbilical Cord in Pregnancies with and without Preeclampsia and Consequent Perinatal Outcomes

OBJECTIVE

To compare redox imbalance and inflammation biomarkers in umbilical cords from pregnancies with and without preeclampsia (PE) and to analyse their relationships with perinatal outcomes.

METHODS

A controlled cross-sectional study was conducted in Maceió, Alagoas, Brazil, that involved pregnant women with PE and a group of women without the disease, through the application of a standardized questionnaire. After delivery, umbilical cord samples were collected to measure antioxidant defense, products from oxidative damage, and inflammation biomarkers such as myeloperoxidase (MPO), interleukin- (IL-) 6, IL-8, IL-10, and tumor necrosis factor-alpha (TNF-α). Statistical analyses were performed using Stata version 13.0 software and IBM Statistical Package for the Social Sciences (SPSS) 20.0, adopting a 95% confidence level (α = 0.05), with the chi-square test, the Wilcoxon-Mann-Whitney test, and the multinomial and Poisson regression tests.

RESULTS

One hundred PE pregnant women and 50 women without the disease were studied. The umbilical cords from PE pregnancies showed higher levels of reduced glutathione (GSH) (p ≤ 0.001), glutathione peroxidase (GPx) (p = 0.016), and malondialdehyde (MDA) (p = 0.028) and lower levels of IL-6 (p = 0.030) and TNF-α (p ≤ 0.001) than the other group, with some associations among these biomarkers with perinatal outcomes.

CONCLUSION

The higher levels of GSH and GPx, in addition to the lower levels of IL-6 and TNF-α, found in the PE umbilical cord, may result from adaptive mechanisms to maintain the oxidative and inflammatory balance; however, despite these changes, the damage to the cell membranes was not minimized, as the MDA level was higher in women with PE than in women without the disease. This implies that a redox imbalance is present, confirming that other physiological and adaptive mechanisms are being activated to preserve foetal health. Therefore, the present work unveils an important role of the umbilical cord in controlling redox imbalance and inflammation in PE pregnancies. Our results reinforce the necessity for continuous research on GSH as a protective compound for the perinatal outcome, especially in PE women.

Oxidative stress-induced impairment of trophoblast function causes preeclampsia through the unfolded protein response pathway

Pre-eclampsia (PE) is a pregnancy-specific disorder, characterized by hypertension and proteinuria. In PE, trophoblasts mediated inadequate remodeling of uterine spiral arteries seem to interrupt uteroplacental blood flow, one of the hallmarks in the early onset of PE (EO-PE). This, in turn, results in placental ischemia–reperfusion injury during hypoxia and reoxygenation episodes, leading to the generation of reactive oxygen species (ROS) and oxidative stress (OS). But still it is debatable if OS is a cause or consequence of PE. In this present study, we have investigated the effects of OS on PE placentae and trophoblast cell functions using BeWo and HTR8/SVneo cell lines. PE placental tissues showed abnormal ultrastructure, high level of reactive oxygen species (ROS) with altered unfolded protein responses (UPR) in compare with term placental tissues. Similar to PE placentae, during OS induction, the trophoblast cells showed altered invasion and migration properties with significantly variable expression of differentiation and invasion markers, e.g., syncytin and MMPs. The effect was rescued by antioxidant, N-acetyl cysteine, thereby implying a ROS-specific effect and in the trophoblast cells, OS triggers UPR pathway through IRE1α-XBP1 axis. Taken together, these findings highlight the harmful effect of unfolded protein response, which was induced due to OS on trophoblast cells and deformed invasion and differentiation programme and can be extended further to clinical settings to identify clinically approved antioxidants during pregnancy as a therapeutic measure to reduce the onset of PE.

The Impact of Early Pregnancy and Exposure to Tobacco Smoke on Blood Antioxidant Status and Copper, Zinc, Cadmium Concentration-A Pilot Study

The aim of the study was to evaluate the impact of early pregnancy and exposure to tobacco smoke on antioxidant status and copper, zinc, and cadmium concentrations in the blood of non-smoking and smoking, as well as non-pregnant or pregnant women. The study included 213 women. More specifically, 150 women in first trimester of pregnancy and 63 non-pregnant women. Women were divided into subgroups according to exposure to tobacco smoke. Pregnancy significant influences higher copper and lower zinc concentration in the serum, whereas exposure to tobacco smoke during pregnancy is mainly associated with an elevation in cadmium and zinc concentration. It seems that metallothionein, superoxide dismutase, and glutathione peroxidase are the important antioxidants during early pregnancy, when exposure to tobacco smoke occurs, whereas the pregnancy itself is associated with a higher concentration of metallothionein and activity of catalase. Both pregnancy in the first trimester and exposure to tobacco smoke decrease glutathione concentration. In addition, active and passive maternal smoking have a similarly negative effect on antioxidant status in the first trimester. Early pregnancy as well as exposure to tobacco smoke is associated with significant alteration in antioxidant status and copper, zinc, and cadmium concentration. Due to a small number of smoking subjects (11 cases of non-pregnant, active smokers and 14 pregnant active smokers), the obtained results should be treated as a pilot, and this should be considered for future studies.

Maternal Psychological and Biological Factors Associated to Gestational Complications

Early detection of gestational complications is a priority in obstetrics. In our social context, this is linked to maternity age. Most studies are focused on biological factors. However, pregnancy is also influenced by social and psychological factors, which have not been deeply explored. We aimed to identify biopsychosocial risk and protective factors associated with the development of maternal and fetal complications. We enrolled 182 healthy pregnant women, and plasma melatonin and cortisol levels were measured in the first trimester by chemiluminescent immunoassays. At different time points along gestation, women answered several questionnaires (positive and negative affect schedule, hospital anxiety and depression scale, pregnancy concerns scale, life orientation test, resilience scale, life satisfaction scale and life-work conflicts scale). They were followed up until delivery and categorized as normal pregnancy, maternal or fetal complications. Maternal complications were associated with low melatonin (OR = 0.99 [0.98; 1.00]; p-value = 0.08) and life satisfaction (OR = 0.64 [0.41; 0.93]; p-value = 0.03) and fetal complications were associated with high cortisol (OR = 1.06 [1.02; 1.13]; p-value = 0.04), anxiety (OR = 2.21 [1.10; 4.55]; p-value = 0.03) and life-work conflicts (OR = 1.92 [1.04; 3.75]; p-value = 0.05). We conclude that psychological factors influence pregnancy outcomes in association with melatonin and cortisol alterations. High maternal melatonin and life satisfaction levels could be potential protective factors against the development of maternal complications during pregnancy. Low anxiety and cortisol levels and reduced work-life conflicts could prevent fetal complications.

Integrated analysis of multiple microarray studies to identify novel gene signatures in preeclampsia

INTRODUCTION

Preeclampsia (PE) is one of the major causes of maternal and fetal morbidity and mortality in pregnancy worldwide. However, the intrinsic molecular mechanisms underlying the pathogenesis of PE have not yet been fully elucidated.

METHODS

Robust rank aggregation (RRA), weighted correlation network analysis (WGCNA) and protein-protein interaction (PPI) methods were used to identify robust differentially expressed genes (DEGs) and hub genes in preeclampsia and subgroups based on 10 Gene Expression Omnibus (GEO) datasets. Subsequently, enrichment analysis and correlation analysis were performed to explore the potential function of the robust DEGs and hub genes. The diagnostic role of hub genes was further investigated by GSE12767. The miRNA regulators and the effect of hypoxia on hub genes were explored by using GSE84260 and GSE65271, respectively.

RESULTS

Robust DEGs were identified in each subgroup including preeclampsia. Totally, 24 hub genes enriched in inflammatory response, renin-angiotensin system and JAK-STAT pathway, and 24 related miRNA regulators were identified.

DISCUSSION

Our integrated analysis identified novel gene signatures in preeclampsia and subgroups and will contribute to the understanding of comprehensive molecular changes in preeclampsia.

Preeclampsia and Neurodevelopmental Outcomes: Potential Pathogenic Roles for Inflammation and Oxidative Stress?

Preeclampsia (PE) is a common and serious hypertensive disorder of pregnancy that occurs in approximately 3-5% of first-time pregnancies and is a well-known leading cause of maternal and neonatal mortality and morbidity. In recent years, there has been accumulating evidence that in utero exposure to PE acts as an environmental risk factor for various neurodevelopmental disorders, particularly autism spectrum disorder and ADHD. At present, the mechanism(s) mediating this relationship are uncertain. In this review, we outline the most recent evidence implicating a causal role for PE exposure in the aetiology of various neurodevelopmental disorders and provide a novel interpretation of neuroanatomical alterations in PE-exposed offspring and how these relate to their sub-optimal neurodevelopmental trajectory. We then postulate that inflammation and oxidative stress, two prominent features of the pathophysiology of PE, are likely to play a major role in mediating this association. The increased inflammation in the maternal circulation, placenta and fetal circulation in PE expose the offspring to both prenatal maternal immune activation-a risk factor for neurodevelopmental disorders, which has been well-characterised in animal models-and directly higher concentrations of pro-inflammatory cytokines, which adversely affect neuronal development. Similarly, the exaggerated oxidative stress in the mother, placenta and foetus induces the placenta to secrete factors deleterious to neurons, and exposes the fetal brain to directly elevated oxidative stress and thus adversely affects neurodevelopmental processes. Finally, we describe the interplay between inflammation and oxidative stress in PE, and how both systems interact to potentially alter neurodevelopmental trajectory in exposed offspring.

1-O-Hexyl-2,3,5-Trimethylhydroquinone Ameliorates the Development of Preeclampsia through Suppression of Oxidative Stress and Endothelial Cell Apoptosis

1-O-Hexyl-2,3,5-trimethylhydroquinone (HTHQ), a potent nuclear factor-E2-related factor 2 (Nrf2) activator, has potent antioxidant activity by scavenging reactive oxygen species (ROS). However, the role of HTHQ on the development of preeclampsia (PE) and the underlying mechanisms have barely been explored. In the present study, PE model was induced by adenovirus-mediated overexpression of soluble fms-like tyrosine kinase 1 (sFlt-1) in pregnant mice. The results showed that HTHQ treatment significantly relieved the high systolic blood pressure (SBP) and proteinuria and increased the fetal weight and fetal weight/placenta weight in preeclamptic mice. Furthermore, we found that HTHQ treatment significantly decreased soluble endoglin (sEng), endothelin-1 (ET-1), and activin A and restored vascular endothelial growth factor (VEGF) in preeclamptic mice. In addition, HTHQ treatment inhibited oxidative stress and endothelial cell apoptosis by increasing the levels of Nrf2 and its downstream haemoxygenase-1 (HO-1) protein. In line with the data in vivo, we discovered that HTHQ treatment attenuated oxidative stress and cell apoptosis in human umbilical vein endothelial cells (HUVECs) following hypoxia and reperfusion (H/R), and the HTHQ-mediated protection was lost after transfected with siNrf2. In conclusion, these results suggested that HTHQ ameliorates the development of preeclampsia through suppression of oxidative stress and endothelial cell apoptosis.

Association of glutamate cystein ligase (GCL) activity Peroxiredoxin 4 (prxR4) and apelin levels in women with preeclampsia

INTRODUCTION

Preeclampsia is a common disease of pregnancy that is characterized by symptoms such as high blood pressure and proteinuria. Peroxiredoxin 4 (Prx4), is a protein with antioxidant properties which is produced in placenta and protects it from antioxidant stress and recurrent miscarriage. For regeneration of Peroxiredoxin 4 need to glutathione (GSH) and Glutamate-cysteine ligase (GCL) enzyme controls the pathway of glutathione regeneration. Apelin is a paired internal ligand with a G protein coupled receptor and is associated with angiotensin receptor (AT1) as a blood pressure regulator. This study was designed to evaluate GCL enzyme activity and Peroxiredoxin 4, glutathione and apelin levels in serum of women with preeclampsia.

MATERIAL AND METHODS

Thirty pregnant women with preeclampsia and 30 healthy pregnant women were enrolled in this study. All participants were diagnosed by clinical examination and confirmation by Obstetrician-Gynecologist. The GCL enzyme activity and concentration of Prx4 and apelin in serum samples were measured using ready-to-use non-competitive ELISA methods while glutathione level was determined using Ellman's reagent.

RESULTS

The GCL enzyme activity and Prx4 level were significantly lower in preeclampsia compared with control group (p < 0.05). In addition, marked reductions were observed in the concentrations of glutathione and apelin in preeclampsia compared to the healthy pregnant women (p < 0.05).

CONCLUSION

This study identified the role of the GCL and Prx4 system in preeclampsia disorder and may be one of the ways to prevent and reduce the risks of preeclampsia in high-risk women using diet control and stress reduction.

Pre-Pregnancy Obesity vs. Other Risk Factors in Probability Models of Preeclampsia and Gestational Hypertension

In the face of the obesity epidemic around the world, attention should be focused on the role of maternal obesity in the development of pregnancy. The purpose of this analysis was to evaluate the prediction of preeclampsia (PE) and isolated gestational hypertension (GH) for a number of maternal factors, in order to investigate the importance of pre-pregnancy obesity (body mass index, BMI ≥ 30 kg/m²), compared to other risk factors (e.g., prior PE, pregnancy weight gain (GWG), infertility treatment, interpregnancy interval, family history, the lack of vitamin supplementation, urogenital infection, and socioeconomic factors). In total, 912 women without chronic diseases were examined in a Polish prospective cohort of women with a singleton pregnancy (recruited in 2015–2016). Separate analyses were performed for the women who developed GH (n = 113) vs. 775 women who remained normotensive, as well as for those who developed PE (n = 24) vs. 775 controls. The probability of each disease was assessed for the base prediction model (age + primiparity) and for the model extended by one (test) variable, using logistic regression. Three measures were used to assess the prediction: area under curve (AUC) of the base and extended model, integrated discrimination improvement (IDI) (the index shows the difference between the value of the mean change in the predicted probability between the group of sick and healthy women when a new factor is added to the model), and net reclassification improvement (NRI) (the index focuses on the reclassification table describing the number of women in whom an upward or downward shift in the disease probability value occurred after a new factor had been added, including results for healthy and sick women). In the GH prediction, AUC increased most strongly when we added BMI (kg/m²) as a continuous variable (AUC = 0.716, p < 0.001) to the base model. The highest IDI index was obtained for prior GH/PE (IDI = 0.068, p < 0.001). The addition of BMI as a continuous variable or BMI ≥ 25 kg/m² improved the classification for healthy and sick women the most (NRI = 0.571, p < 0.001). In the PE prediction, AUC increased most strongly when we added BMI categories (AUC = 0.726, p < 0.001) to the base model. The highest IDI index was obtained for prior GH/PE (IDI = 0.050, p = 0.080). The addition of BMI categories improved the classification for healthy and sick women the most (NRI = 0.688; p = 0.001). After summing up the results of three indexes, the probability of hypertension in pregnancy was most strongly improved by BMI, including BMI ≥ 25 kg/m² for the GH prediction, and BMI ≥ 30 kg/m² for the PE prediction. Main conclusions: Pre-pregnancy BMI was the most likely factor to increase the probability of developing hypertension in pregnancy, compared to other risk factors. Hierarchies of PE and GH risk factors may suggest different (or common) mechanisms of their development.