Circulating markers of oxidative stress are raised in normal pregnancy and pre-eclampsia

Altered oxidative stress and antioxidant biomarkers concentrations in pregnant individuals exposed to oil and gas sites in Northeastern British Columbia

Northeastern British Columbia is a region of prolific unconventional oil and gas (UOG) activity. UOG activity can release volatile organic compounds (VOCs) which can elevate oxidative stress and disrupt antioxidant activity in exposed pregnant individuals, potentially increasing the risk of adverse pregnancy outcomes. This study measured biomarkers of oxidative stress and antioxidant activity in pooled urine samples of 85 pregnant individuals living in Northeastern British Columbia, to analyze associations between indoor air VOCs, oil and gas well density and proximity metrics, and biomarker concentrations. Concentrations of catalase, superoxide dismutase (SOD), glutathione S-transferase, total antioxidant capacity, 6-hydroxymelatonin sulfate (aMT6s), malondialdehyde (MDA), 8-hydroxy-2'-deoxyguanosine (8-OHdG), and 8-isoprostane were measured using assay kits. Associations between exposure metrics and biomarker concentrations were determined using multiple linear regression models adjusted for biomarker-specific covariables. UOG proximity was associated with decreased SOD and 8-OHdG. Decreased 8-OHdG was associated with increased proximity to all wells. Decreased aMT6s were observed with increased indoor air hexanal concentrations. MDA was negatively associated with indoor air 1,4-dioxane concentrations. No statistically significant associations were found between other biomarkers and exposure metrics. Although some associations linked oil and gas activity to altered oxidative stress and antioxidant activity, the possibility of chance findings due to the large number of tests cannot be discounted. This study shows that living near UOG wells may alter oxidative stress and antioxidant activity in pregnant individuals. More research is needed to elucidate underlying mechanisms and to what degree UOG activity affects oxidative stress and antioxidant activity.

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.

Endothelial cell vasodilator dysfunction mediates progressive pregnancy-induced hypertension in endothelial cell tetrahydrobiopterin deficient mice

BACKGROUND AND PURPOSE

Pregnancy-associated vascular remodelling is essential for both maternal and fetal health. We have previously shown that maternal endothelial cell tetrahydrobiopterin (BH4) deficiency causes poor pregnancy outcomes. Here, we investigated the role and mechanisms of endothelial cell-mediated vasorelaxation function in these outcomes.

EXPERIMENTAL APPROACH

The vascular reactivity of mouse aortas and uterine arteries from non-pregnant and pregnant endothelial cell-specific BH4 deficient mice (Gch1fl/flTie2cre mice) was assessed by wire myography. Systolic blood pressure was assessed by tail cuff plethysmography.

KEY RESULTS

In late pregnancy, systolic blood pressure was significantly higher (∼24 mmHg) in Gch1fl/flTie2cre mice compared with wild-type littermates. This was accompanied by enhanced vasoconstriction and reduced endothelial-dependent vasodilation in both aorta and uterine arteries from pregnant Gch1fl/flTie2cre mice. In uterine arteries loss of eNOS-derived vasodilators was partially compensated by upregulation of intermediate and large-conductance Ca2+-activated K+ channels. In rescue experiments, oral BH4 supplementation alone did not rescue vascular dysfunction and pregnancy-induced hypertension in Gch1fl/flTie2cre mice. However, combination with the fully reduced folate, 5-methyltetrahydrofolate (5-MTHF), restored endothelial cell vasodilator function and blood pressure.

CONCLUSIONS AND IMPLICATIONS

We identify a critical requirement for maternal endothelial cell Gch1/BH4 biosynthesis in endothelial cell vasodilator function in pregnancy. Targeting vascular Gch1 and BH4 biosynthesis with reduced folates may provide a novel therapeutic target for the prevention and treatment of pregnancy-related hypertension.

Defining the nuanced nature of redox biology in post-traumatic stress disorder

Post-traumatic stress disorder (PTSD) is a mental health disorder that arises after experiencing or witnessing a traumatic event. Despite affecting around 7% of the population, there are currently no definitive biological signatures or biomarkers used in the diagnosis of PTSD. Thus, the search for clinically relevant and reproducible biomarkers has been a major focus of the field. With significant advances of large-scale multi-omic studies that include genomic, proteomic, and metabolomic data, promising findings have been made, but the field still has fallen short. Amongst the possible biomarkers examined, one area is often overlooked, understudied, or inappropriately investigated: the field of redox biology. Redox molecules are free radical and/or reactive species that are generated as a consequence of the necessity of electron movement for life. These reactive molecules, too, are essential for life, but in excess are denoted as "oxidative stress" and often associated with many diseases. The few studies that have examined redox biology parameters have often utilized outdated and nonspecific methods, as well as have reported confounding results, which has made it difficult to conclude the role for redox in PTSD. Herein, we provide a foundation of how redox biology may underlie diseases like PTSD, critically examine redox studies of PTSD, and provide future directions the field can implement to enhance standardization, reproducibility, and accuracy of redox assessments for the use of diagnosis, prognosis, and therapy of this debilitating mental health disorder.

Upregulation of exofacial peroxiredoxin-thioredoxin system of lymphocytes and monocytes in preeclampsia

OBJECTIVES

An imbalanced redox homeostasis resulting in oxidative stress is present in preeclampsia. Peroxiredoxin-1 (PRDX1) and thioredoxin-1 (TRX1) regulatory enzymes are also contributing to the redox homeostasis, but were not investigated so far in preeclampsia. Thus, we have aimed to characterize PRDX1, TRX1 and oxidative stress biomarkers in blood samples of pregnant women with preeclampsia.

STUDY DESIGN

Twelve patients with preeclampsia (PE) were enrolled into the study. Seven third trimester healthy pregnant women (HP) were accepted as control group.

MAIN OUTCOME MEASURES

Peripheral venous blood samples of healthy and preeclamptic pregnant women were analyzed. Plasma level of advanced oxidation protein products (AOPP) was determined by spectrophotometry. The exofacial PRDX1 and TRX1 expression of lymphocytes and monocytes was detected by flow cytometry.

RESULTS

The plasma AOPP level was significantly higher in preeclampsia compared to the healthy pregnant group. Significantly higher percentage of PRDX1 and TRX1 expressing lymphocytes and monocytes were detected in the blood samples of preeclamptic women compared to healthy pregnant controls. The ratio of circulating PRDX1 and TRX1 expressing lymphocytes and monocytes showed a significant inverse correlation with the birth weight of newborns.

CONCLUSIONS

We have revealed that the level of advanced oxidation protein products is increased and the exofacial peroxiredoxin-1 and thioredoxin-1 system in lymphocytes and monocytes is upregulated in preeclampsia. In addition, the ratio of peroxiredoxin-1 and thioredoxin-1 positive circulating lymphocytes and monocytes correlates inversely with the neonatal birth weight, which finding indicates that pregnancies complicated by intrauterine growth restriction are accompanied by a higher level of oxidative stress.

Is human labor at term an inflammatory condition?†

Parturition at term in normal pregnancy follows a predictable sequence of events. There is some evidence that a state of inflammation prevails in the reproductive tissues during labor at term, but it is uncertain whether this phenomenon is the initiating signal for parturition. The absence of a clear temporal sequence of inflammatory events prior to labor casts doubt on the concept that normal human labor at term is primarily the result of an inflammatory cascade. This review examines evidence linking parturition and inflammation in order to address whether inflammation is a cause of labor, a consequence of labor, or a separate but related phenomenon. Finally, we identify and suggest ways to reconcile inconsistencies regarding definitions of labor onset in published research, which may contribute to the variability in conclusions regarding the genesis and maintenance of parturition. A more thorough understanding of the processes underlying normal parturition at term may lead to novel insights regarding abnormal labor, including spontaneous preterm labor, preterm premature rupture of the fetal membranes, and dysfunctional labor, and the role of inflammation in each.

Prediction of preeclampsia throughout gestation with maternal characteristics and biophysical and biochemical markers: a longitudinal study

BACKGROUND

The current approach to predict preeclampsia combines maternal risk factors and evidence from biophysical markers (mean arterial pressure, Doppler velocimetry of the uterine arteries) and maternal blood proteins (placental growth factor, soluble vascular endothelial growth factor receptor-1, pregnancy-associated plasma protein A). Such models require the transformation of biomarker data into multiples of the mean values by using population- and site-specific models. Previous studies have focused on a narrow window in gestation and have not included the maternal blood concentration of soluble endoglin, an important antiangiogenic factor up-regulated in preeclampsia.

OBJECTIVE

This study aimed (1) to develop models for the calculation of multiples of the mean values for mean arterial pressure and biochemical markers; (2) to build and assess the predictive models for preeclampsia based on maternal risk factors, the biophysical (mean arterial pressure) and biochemical (placental growth factor, soluble vascular endothelial growth factor receptor-1, and soluble endoglin) markers collected throughout pregnancy; and (3) to evaluate how prediction accuracy is affected by the presence of chronic hypertension and gestational age.

STUDY DESIGN

This longitudinal case-cohort study included 1150 pregnant women: women without preeclampsia with (n=49) and without chronic hypertension (n=871) and those who developed preeclampsia (n=166) or superimposed preeclampsia (n=64). Mean arterial pressure and immunoassay-based maternal plasma placental growth factor, soluble vascular endothelial growth factor receptor-1, and soluble endoglin concentrations were available throughout pregnancy (median of 5 observations per patient). A prior-risk model for preeclampsia was established by using Poisson regression based on maternal characteristics and obstetrical history. Next, multiple regression was used to fit biophysical and biochemical marker data as a function of maternal characteristics by using data collected at 8 to 15⁺⁶, 16 to 19⁺⁶, 20 to 23⁺⁶, 24 to 27⁺⁶, 28 to 31⁺⁶, and 32 to 36⁺⁶ week intervals, and observed values were converted into multiples of the mean values. Then, multivariable prediction models for preeclampsia were fit based on the biomarker multiples of the mean data and prior-risk estimates. Separate models were derived for overall, preterm, and term preeclampsia, which were evaluated by receiver operating characteristic curves and sensitivity at fixed false-positive rates.

RESULTS

(1) The inclusion of soluble endoglin in prediction models for all preeclampsia, together with the prior-risk estimates, mean arterial pressure, placental growth factor, and soluble vascular endothelial growth factor receptor-1, increased the sensitivity (at a fixed false-positive rate of 10%) for early prediction of superimposed preeclampsia, with the largest increase (from 44% to 54%) noted at 20 to 23⁺⁶ weeks (McNemar test, P<.05); (2) combined evidence from prior-risk estimates and biomarkers predicted preterm preeclampsia with a sensitivity (false-positive rate, 10%) of 55%, 48%, 62%, 72%, and 84% at 8 to 15⁺⁶, 16 to 19⁺⁶, 20 to 23⁺⁶, 24 to 27⁺⁶, and 28 to 31⁺⁶ week intervals, respectively; (3) the sensitivity for term preeclampsia (false-positive rate, 10%) was 36%, 36%, 41%, 43%, 39%, and 51% at 8 to 15⁺⁶, 16 to 19⁺⁶, 20 to 23⁺⁶, 24 to 27⁺⁶, 28 to 31⁺⁶, and 32 to 36⁺⁶ week intervals, respectively; (4) the detection rate for superimposed preeclampsia among women with chronic hypertension was similar to that in women without chronic hypertension, especially earlier in pregnancy, reaching at most 54% at 20 to 23⁺⁶ weeks (false-positive rate, 10%); and (5) prediction models performed comparably to the Fetal Medicine Foundation calculators when the same maternal risk factors and biomarkers (mean arterial pressure, placental growth factor, and soluble vascular endothelial growth factor receptor-1 multiples of the mean values) were used as input.

CONCLUSION

We introduced prediction models for preeclampsia throughout pregnancy. These models can be useful to identify women at risk during the first trimester who could benefit from aspirin treatment or later in pregnancy to inform patient management. Relative to prediction performance at 8 to 15⁺⁶ weeks, there was a substantial improvement in the detection rate for preterm and term preeclampsia by using data collected after 20 and 32 weeks' gestation, respectively. The inclusion of plasma soluble endoglin improves the early prediction of superimposed preeclampsia, which may be valuable when Doppler velocimetry of the uterine arteries is not available.

Arterial Stiffness as a Cardiovascular Risk Factor for the Development of Preeclampsia and Pharmacopreventive Options

Arterial stiffness (AS) describes the rigidity of the arterial walls. Epidemiological studies have shown that increased AS is an independent predictive marker of cardiovascular (CV) morbidity and mortality in both pregnant and non-pregnant women. Preeclampsia (PE), a form of pregnancy-induced hypertension, affects approximately 5% of pregnancies worldwide. Preeclamptic women have a higher risk of CV disease (CVD), mainly because PE damages the heart's ability to relax between contractions. Different pharmacological approaches for the prevention of PE have been tested in clinical trials (e.g. aspirin, enoxaparin, metformin, pravastatin, and sildenafil citrate). In current clinical practice, only low-dose aspirin is used for PE pharmacoprevention. However, low-dose aspirin does not prevent term PE, which is the most common form of PE. Compromised vascular integrity precedes the onset of PE and therefore, AS assessment may constitute a promising predictive marker of PE. Several non-invasive techniques have been developed to assess AS. Compared with normotensive pregnancies, both carotid-femoral pulse wave velocity (cfPWV) and augmentation index (AIx) are increased in PE. In view of simplicity, reliability, and reproducibility, there is an interest in oscillometric AS measurements in pregnancies complicated by PE.

Vitamin C Deficiency in the Young Brain-Findings from Experimental Animal Models

Severe and long-term vitamin C deficiency can lead to fatal scurvy, which is fortunately considered rare today. However, a moderate state of vitamin C (vitC) deficiency (hypovitaminosis C)-defined as a plasma concentration below 23 μM-is estimated to affect up to 10% of the population in the Western world, albeit clinical hallmarks in addition to scurvy have not been linked to vitC deficiency. The brain maintains a high vitC content and uniquely high levels during deficiency, supporting vitC's importance in the brain. Actions include both antioxidant and co-factor functions, rendering vitamin C deficiency likely to affect several targets in the brain, and it could be particularly significant during development where a high cellular metabolism and an immature antioxidant system might increase sensitivity. However, investigations of a non-scorbutic state of vitC deficiency and effects on the developing young brain are scarce. This narrative review provides a comprehensive overview of the complex mechanisms that regulate vitC homeostasis in vivo and in the brain in particular. Functions of vitC in the brain and the potential consequences of deficiency during brain development are highlighted, based primarily on findings from experimental animal models. Perspectives for future investigations of vitC are outlined.

Maternal Urinary Metal and Metalloid Concentrations in Association with Oxidative Stress Biomarkers

Metal exposure has been associated with a wide range of adverse birth outcomes and oxidative stress is a leading hypothesis of the mechanism of action of metal toxicity. We assessed the relationship between maternal exposure to essential and non-essential metals and metalloids in pregnancy and oxidative stress markers, and sought to identify windows of vulnerability and effect modification by fetal sex. In our analysis of 215 women from the PROTECT birth cohort study, we measured 14 essential and non-essential metals in urine samples at three time points during pregnancy. The oxidative stress marker 8-iso-prostaglandin F2α (8-iso-PGF2α) and its metabolite 2,3-dinor-5,6-dihydro-15-15-F2t-IsoP, as well as prostaglandin F2α (PGF2α), were also measured in the same urine samples. Using linear mixed models, we examined the main effects of metals on markers of oxidative stress as well as the visit-specific and fetal sex-specific effects. After adjustment for covariates, we found that a few urinary metal concentrations, most notably cesium (Cs) and copper (Cu), were associated with higher 8-iso-PGF2α with effect estimates ranging from 7.3 to 14.9% for each interquartile range, increase in the metal concentration. The effect estimates were generally in the same direction at the three visits and a few were significant only among women carrying a male fetus. Our data show that higher urinary metal concentrations were associated with elevated biomarkers of oxidative stress. Our results also indicate a potential vulnerability of women carrying a male fetus.

Hypoxia-reoxygenation treatment attenuates gestational diabetes mellitus

BACKGROUND

Oxidative stress leads to insulin resistance and gestational diabetes mellitus (GDM). The nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling is an important anti-oxidative stress pathway, which can be activated by hypoxia-reoxygenation (H/R) treatment. We aimed to demonstrate the effects of H/R treatment on GDM symptoms as well as reproductive outcomes.

METHODS

Pregnant C57BL/KsJ db/+ mice were used as a genetic GDM model. Plasma insulin and other biochemical indexes of plasma, insulin sensitivity, glucose intolerance, blood glucose and liver biochemical indexes were evaluated. Protein abundance of HO-1 and Nrf2 were assessed with Western blot.

RESULTS

H/R treatment markedly ameliorated β-cell insufficiency and glucose intolerance, suppressed oxidative stress in vivo, stimulated the activities of anti-oxidant enzymes, and led to improved reproductive outcomes. The beneficial effects of H/R treatment were mechanistically mediated via the restoration of Nrf2/HO-1 anti-oxidant signaling pathway in the liver of GDM mice.

CONCLUSION

Our study, for the first time, suggests that H/R treatment is a potentially novel therapeutic approach against GDM symptoms, by activating the Nrf2/HO-1 signaling pathway and inhibiting oxidative stress.

Astaxanthin alleviates gestational diabetes mellitus in mice through suppression of oxidative stress

Gestational diabetes mellitus (GDM) affects 7% of pregnant women worldwide, which increases the risk of diabetes and cardiovascular disease for both the mother and the fetus. Natural compound Astaxanthin has been reported to have benefits in obesity and diabetes. A pregnant C57BL/KsJ db/+ mouse was used as a genetic GDM model to investigate the effect of Astaxanthin on GDM symptoms and reproductive outcomes. Blood glucose, plasma insulin, glucose intolerance, insulin sensitivity, biochemical indexes of plasma, and the liver were measured; Nrf2 and HO-1 protein levels were detected by Western blotting. Astaxanthin significantly alleviated the glucose intolerance and β cell insufficiency, inhibited in vivo oxidative stress, enhanced the activity of antioxidant enzymes, and improved reproductive outcomes. Mechanistically, the effect of Astaxanthin was mediated by restoring the Nrf2/HO-1 antioxidant pathway in the liver of GDM mice. Our findings supported that Astaxanthin was a potential therapeutic reagent for not only diabetes but also GDM symptomology.

SERPINA1 Gene Promoter Is Differentially Methylated in Peripheral Blood Mononuclear Cells of Pregnant Women

SERine Protein INhibitor-A1 (SERPINA1) is an inducible blood cell gene coding for alpha1-antitrypsin (AAT), a plasma protease inhibitor whose circulating levels are raised during inflammation, infection and advanced pregnancy. DNA methylation has been suggested to play a role in SERPINA1 gene expression regulation in peripheral blood mononuclear cells (PBMCs). The methylation status of SERPINA1 in PBMCs is unknown. The aim of this study was to evaluate the methylation profile of the SERPINA1 promoter in PBMC. To this purpose PBMCs and serum were collected from healthy subjects (HS) (n = 75), including blood donors (BD) (n = 25), pregnant women at early pregnancy (EP) (n = 25), i.e., within the first trimester, and pregnant women at late pregnancy (LP) (n = 25), i.e., at the third trimester. DNA from PBMCs was treated with sodium bisulfite and PCR amplified for SERPINA1 gene promoter, followed by sequencing analyses. AAT serum levels were determined by ELISA test. SERPINA1 was found hypermethylated in 58.7% of HS. The prevalence of SERPINA1 hypermethylation was significantly higher in BD (68%) and EP (88%) than in LP (20%) (p < 0.01). The median serum AAT concentration was 1.07, 0.63, and 3.15 mg/ml in BD, EP, and LP, respectively (p < 0.05, BD and EP vs LP). This study indicates, for the first time, that SERPINA1 gene promoter is differentially methylated in PBMCs from HS. Likely, modulation of the methylation may be a novel epigenetic regulator mechanism of AAT expression in the PBMC of HS. Therefore, SERPINA1 gene promoter methylation may represent an epigenetic biomarker of PBMCs in healthy subjects.

Update on oxidative stress and inflammation in pregnant women, unborn children (nasciturus), and newborns - Nutritional and dietary effects

The scientific background of perinatal pathology, regarding both mother and offspring, from the lipidomic perspective, has highlighted the possibility of identifying new, promising clinical markers of oxidative stress and inflammation, closely related to the normal development of unborn and newborn children, together with their application. In this regard, in recent years, significant advances have been achieved, assisted by both newly developed analytical tools and basic knowledge on the biological implications of oxylipins. Hence, in the light of this recent progress, this review aims to provide an update on the relevance of human oxylipins during pregnancy and in the unborn and newborn child, covering two fundamental aspects. Firstly, the evidence from human clinical studies and dietary intervention trials will be used to shed light on the extent to which dietary supplementation can modulate the lipidomic markers of oxidative stress and inflammation in the perinatal state, emphasizing the role of the placenta and metabolic disturbances in the mother and fetus. The second part of this article comprises a review of existing data on specific pathophysiological aspects of human reproduction, in relation to lipidomic markers in pregnant women, unborn children, and newborn children. The information reviewed here evidences the current opportunity to correct reproductive disturbances, in the framework of lipidomics, by fine-tuning dietary interventions.

Alpha-1 microglobulin as a potential therapeutic candidate for treatment of hypertension and oxidative stress in the STOX1 preeclampsia mouse model

Preeclampsia is a human placental disorder affecting 2–8% of pregnancies worldwide annually, with hypertension and proteinuria appearing after 20 weeks of gestation. The underlying cause is believed to be incomplete trophoblast invasion of the maternal spiral arteries during placentation in the first trimester, resulting in oxidative and nitrative stress as well as maternal inflammation and organ alterations. In the Storkhead box 1 (STOX1) preeclampsia mouse model, pregnant females develop severe and early onset manifestations as seen in human preeclampsia e.g. gestational hypertension, proteinuria, and organ alterations. Here we aimed to evaluate the therapeutic potential of human recombinant alpha-1 microglobulin (rA1M) to alleviate the manifestations observed. Human rA1M significantly reduced the hypertension during gestation and significantly reduced the level of hypoxia and nitrative stress in the placenta. In addition, rA1M treatment reduced cellular damage in both placenta and kidneys, thereby protecting the tissue and improving their function. This study confirms that rA1M has the potential as a therapeutic drug in preeclampsia, and likely also in other pathological conditions associated with oxidative stress, by preserving normal organ function.

Natural killer cells contribute to mitochondrial dysfunction in response to placental ischemia in reduced uterine perfusion pressure rats

Preeclampsia (PE) is characterized by new-onset hypertension during pregnancy and is associated with immune activation and placental oxidative stress. Mitochondrial dysfunction is a major source of oxidative stress and may play a role in the pathology of PE. We (Vaka VR, et al. Hypertension 72: 703-711, 2018. doi: 10.1161/HYPERTENSIONAHA.118.11290 .) have previously shown that placental ischemia is associated with mitochondrial oxidative stress in the reduced uterine perfusion pressure (RUPP) model of PE. Furthermore, we have also shown that placental ischemia induces natural killer (NK) cell activation in RUPP. Thus, we hypothesize that NK cell depletion could improve mitochondrial function associated with hypertension in the RUPP rat model of PE. Pregnant Sprague-Dawley rats were divided into three groups: normal pregnant (NP), RUPP, and RUPP+NK cell depletion rats (RUPP+NKD). On gestational day (GD)14, RUPP surgery was performed, and NK cells were depleted by administering anti-asialo GM1 antibodies (3.5 µg/100 µl ip) on GD15 and GD17. On GD19, mean arterial pressure (MAP) was measured, and placental mitochondria were isolated and used for mitochondrial assays. MAP was elevated in RUPP versus NP rats (119 ± 1 vs.104 ± 2 mmHg, P = 0.0004) and was normalized in RUPP+NKD rats (107 ± 2 mmHg, P = 0.002). Reduced complex IV activity and state 3 respiration rate were improved in RUPP+NKD rats. Human umbilical vein endothelial cells treated with RUPP+NKD serum restored respiration with reduced mitochondrial reactive oxygen species (ROS). The restored placental or endothelial mitochondrial function along with attenuated endothelial cell mitochondrial ROS with NK cell depletion indicate an important role of NK cells in mediating mitochondrial oxidative stress in the pathology of PE.

Mechanisms of Sex Disparities in Cardiovascular Function and Remodeling

Epidemiological studies demonstrate disparities between men and women in cardiovascular disease prevalence, clinical symptoms, treatments, and outcomes. Enrollment of women in clinical trials is lower than men, and experimental studies investigating molecular mechanisms and efficacy of certain therapeutics in cardiovascular disease have been primarily conducted in male animals. These practices bias data interpretation and limit the implication of research findings in female clinical populations. This review will focus on the biological origins of sex differences in cardiovascular physiology, health, and disease, with an emphasis on the sex hormones, estrogen and testosterone. First, we will briefly discuss epidemiological evidence of sex disparities in cardiovascular disease prevalence and clinical manifestation. Second, we will describe studies suggesting sexual dimorphism in normal cardiovascular function from fetal life to older age. Third, we will summarize and critically discuss the current literature regarding the molecular mechanisms underlying the effects of estrogens and androgens on cardiac and vascular physiology and the contribution of these hormones to sex differences in cardiovascular disease. Fourth, we will present cardiovascular disease risk factors that are positively associated with the female sex, and thus, contributing to increased cardiovascular risk in women. We conclude that inclusion of both men and women in the investigation of the role of estrogens and androgens in cardiovascular physiology will advance our understanding of the mechanisms underlying sex differences in cardiovascular disease. In addition, investigating the role of sex-specific factors in the development of cardiovascular disease will reduce sex and gender disparities in the treatment and diagnosis of cardiovascular disease. © 2019 American Physiological Society. Compr Physiol 9:375-411, 2019.

Melatonin treatment in fetal and neonatal diseases

This literature review aims to address the main scientific findings on oxidative stress activity in different gestational disorders, as well as the function and application of melatonin in the treatment of fetal and neonatal changes. Oxidative stress has been associated with the etiopathogenesis of recurrent miscarriages, preeclampsia, intrauterine growth restriction, and stillbirth. Both, the exacerbated consumption of the antioxidant enzymes superoxide dismutase, catalase and glutathione peroxidase, and the increased synthesis of reactive oxygen species, such as superoxide, peroxynitrite, and hydrogen peroxide, induce phospholipid peroxidation and endothelial dysfunction, impaired invasion and death of trophoblast cells, impaired decidualization, and remodeling of maternal spiral arteries. It has been postulated that melatonin induces specific biochemical responses that regulate cell proliferation in fetuses, and that its antioxidant action promotes bioavailability of nitric oxide and, thus, placental perfusion and also fetal nutrition and oxygenation. Therefore, the therapeutic action of melatonin has been the subject of major studies that aim to minimize or prevent different injuries affecting this pediatric age group, such as intrauterine growth restriction, encephalopathy, chronic lung diseases, retinopathy of prematurity Conclusion: the results antioxidant and indicate that melatonin is an important therapy for the clinical treatment of these diseases.

Strontium and oxidative stress in normal pregnancy

BACKGROUND

Pregnancy brings about metabolic and oxidative changes that involve various trace elements and oxidative stress. Strontium (Sr) is a trace element scarcely studied in this context, although it has been suggested that it may play a role in the pathophysiology of preeclampsia. The main aim of this study was to evaluate Sr concentrations and oxidative status in normal pregnancy.

METHODS

The study population included non-pregnant women (n=31), healthy pregnant women in the first (n=50), second (n=51) and third (n=53) trimesters of gestation, and women in postpartum period (n=31). Additionally, samples from another twenty pregnant women were obtained in the three trimesters. Strontium, copper, selenium and zinc were measured by inductively coupled plasma-mass spectrometry. Calcium (Ca), uric acid (UA), lipid peroxidation and total antioxidant activity (TAA) were measured by spectrophotometric assays.

RESULTS

Strontium remained unchanged until the third trimester of pregnancy, in which significantly higher levels were found (p=0.001). The other elements showed diverse trends during pregnancy. Uric acid levels were significantly different in all groups (p<0.001), increasing gradually as the pregnancy progresses. In serial samples, there was a statistically significant positive correlation between Sr and gestational week of sampling (r=0.31, p=0.01), UA (r=0.40, p=0.001) and lipid peroxidation/TAA ratio (r=0.38, p=0.0002). Additionally, Sr correlated negatively with TAA (r=-0.40, p=0.0001).

CONCLUSION

Strontium seems to play a physiological role in the oxidative status of the human organism. Further studies involving Sr and pathologies of pregnancy are warranted.

Chronic hypertension: effect of blood pressure control on pregnancy outcome

OBJECTIVE

To examine whether in patients with CH and mild to moderate hypertension the level of control of blood pressure during pregnancy has a beneficial or adverse effect on the risk of PE or SGA.

METHODS

We performed a systematic review and meta-analysis of randomized controlled trials of patients with mild to moderate CH in pregnancy that reported the impact of different levels of control of blood pressure on the risk of PE or SGA. We completed a literature search through PubMed, Embase, Cinahl, Web of science, Cochrane CENTRAL Library Relative risks with random effect were calculated with their 95% confidence intervals (95%CI).

RESULTS

Six trials including 495 participants provided data on blood pressure (BP) after entry to the study. Four studies compared antihypertensive agents to no treatment and two studies compared antihypertensive agents to placebo. All trials were conducted between 1976 and 1990 and were considered to be at high risk of bias. There was high heterogeneity between studies for mean arterial pressure (MAP) after randomization (I² = 87%) and SGA (I² = 60%), but not for PE (I² = 0%). There were large differences between studies in the inclusion criteria, antihypertensive regimens, targets of therapy, and gestational age range at entry to the trials. In women receiving antihypertensive therapy, compared to those receiving placebo or no treatment, the MAP after entry to the trial was significantly lower (mean difference -4.2 mmHg, 95%CI -6.6 to -1.8; p = .006). However, there was no significant reduction in the risk of PE (relative risks (RR) 1.03, 95%CI 0.63-1.68; p = .90) or SGA (RR 1.01, 95%CI 0.35-2.93; p = .99).

CONCLUSIONS

The findings of the meta-analysis suggest that lowering the blood pressure by antihypertensive medication in women with mild to moderate hypertension in the context of CH has no significant effect on the risk of SGA or PE.

Aspirin for Evidence-Based Preeclampsia Prevention trial: effect of aspirin in prevention of preterm preeclampsia in subgroups of women according to their characteristics and medical and obstetrical history

BACKGROUND

The Combined Multimarker Screening and Randomized Patient Treatment with Aspirin for Evidence-Based Preeclampsia Prevention trial demonstrated that in women who were at high risk for preterm preeclampsia with delivery at <37 weeks' gestation identified by screening by means of an algorithm that combines maternal factors and biomarkers at 11-13 weeks' gestation, aspirin administration from 11 to 14 until 36 weeks' gestation was associated with a significant reduction in the incidence of preterm preeclampsia (odds ratio 0.38; 95% confidence interval, 0.20 to 0.74; P=0.004).

OBJECTIVE

We sought to examine whether there are differences in the effect of aspirin on the incidence of preterm preeclampsia in the Aspirin for Evidence-Based Preeclampsia Prevention trial in subgroups defined according to maternal characteristics and medical and obstetrical history.

STUDY DESIGN

This was a secondary analysis of data from the Aspirin for Evidence-Based Preeclampsia Prevention trial. Subgroup analysis was performed to assess evidence of differences in the effect of aspirin on incidence of preterm preeclampsia in subgroups defined by maternal age (<30 and ≥30 years), body mass index (<25 and ≥25 kg/m²), racial origin (Afro-Caribbean, Caucasian and other), method of conception (natural and assisted), cigarette smoking (smoker and non-smoker), family history of preterm preeclampsia (present and absent), obstetrical history (nulliparous, multiparous with previous preterm preeclampsia and multiparous without previous preterm preeclampsia), history of chronic hypertension (present and absent). Interaction tests were performed on the full data set of patients in the intention to treat population and on the data set of patients who took ≥ 90% of the prescribed medication. Results are presented as forest plot with P values for the interaction effects, group sizes, event counts and estimated odds ratios. We examined whether the test of interaction was significant at the 5% level with a Bonferroni adjustment for multiple comparisons.

RESULTS

There was no evidence of heterogeneity in the aspirin effect in subgroups defined according to maternal characteristics and obstetrical history. In participants with chronic hypertension preterm preeclampsia occurred in 10.2% (5/49) in the aspirin group and 8.2% (5/61) in the placebo group (adjusted odds ratio, 1.29; 95% confidence interval, 0.33-5.12). The respective values in those without chronic hypertension were 1.1% (8/749) in the aspirin group and 3.9% (30/761) in the placebo group (adjusted odds ratio, 0.27; 95% confidence interval, 0.12-0.60). In all participants with adherence of ≥90% the adjusted odds ratio in the aspirin group was 0.24 (95% confidence interval, 0.09-0.65); in the subgroup with chronic hypertension it was 2.06 (95% confidence interval, 0.40-10.71); and in those without chronic hypertension it was 0.05 (95% confidence interval, 0.01-0.41). For the complete data set the test of interaction was not significant at the 5% level (P = .055), but in those with adherence ≥90%, after adjustment for multiple comparisons, the interaction was significant at the 5% level (P = .0019).

CONCLUSION

The beneficial effect of aspirin in the prevention of preterm preeclampsia may not apply in pregnancies with chronic hypertension. There was no evidence of heterogeneity in the aspirin effect in subgroups defined according to maternal characteristics and obstetrical history.

Impaired placentation in women with chronic hypertension who develop pre-eclampsia

OBJECTIVE

To compare the degree of impaired placentation in women with and those without chronic hypertension (CH) who develop pre-eclampsia (PE) in pregnancy.

METHODS

Data were derived from prospective screening for adverse pregnancy outcomes in women with singleton pregnancy attending their first routine hospital visit at 11 + 0 to 13 + 6 weeks' gestation. This visit included recording of maternal characteristics and medical history and measurement of mean arterial pressure (MAP), uterine artery pulsatility index (UtA-PI), serum placental growth factor (PlGF) and serum pregnancy-associated plasma protein-A (PAPP-A). The measured biomarkers were converted to multiples of the median (MoM) after adjustment for pregnancy characteristics. MoM values in women with CH who developed PE (n = 283) were compared to those of women without CH who developed PE (n = 2236).

RESULTS

In both groups with and without CH, measurements of MAP and UtA-PI were increased, whereas those of PlGF and PAPP-A were decreased and the deviation from normal in all biomarkers decreased with advancing gestational age at delivery with PE. There was no significant difference between women with and those without CH in the slope of the regression line of log₁₀ MoM biomarker values against gestational age at delivery with PE for any of the biomarkers. However, there was a significant difference in the intercepts and coefficients of biomarkers in the two groups; compared to those without CH, MAP MoM, PlGF MoM and PAPP-A MoM were higher and UtA-PI MoM was lower in the CH group (all P < 0.01).

CONCLUSION

In pregnancies that develop PE, the degree of impaired placentation, reflected in high UtA-PI and low PlGF and PAPP-A at 11-13 weeks' gestation, is less in women with CH than in those without CH. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Higher Level of Oxidative Stress Markers in Small for Gestational Age Newborns Delivered by Cesarean Section at Term

INTRODUCTION

The aim of our study was to determine lipid peroxidation products and antioxidant enzyme activity in umbilical cord blood of small for gestational age (SGA) neonates.

MATERIALS AND METHODS

Umbilical cord arterial blood samples were collected from 21-term singleton SGA newborn infants and 21 age- and sex-matched appropriate for gestational age (AGA) term neonates prospectively born by elective cesarean section for determination of malondialdehyde (MDA) as a marker of lipid peroxidation and superoxide dismutase (SOD) for antioxidant activity.

RESULTS

MDA levels were increased (5.20 vs. 3.52 nmol/mL; p < 0.001), while levels of SOD (6.24 vs. 8.99 U/mL; p < 0.01) were decreased in SGA neonates when compared with AGA newborn infants.

CONCLUSIONS

Elevated MDA levels and decreased SOD activity in umbilical cord blood may show the possibility of insufficient protective mechanisms against increased oxidative stress in SGA neonates born by cesarean section.

Biomarkers of oxidative stress in pregnancy complications

Pregnancy complications including pre-eclampsia, gestational-diabetes mellitus, preterm birth and intrauterine growth restriction can cause acute and chronic health problems for the mother and lead to fetal loss or dysregulation of infant physiology. The human placenta is susceptible to oxidative stress and oxidative damage in early gestation contributes to the onset of these conditions later in pregnancy. Current methods of predicting pregnancy complications are limited and although a large number of factors are associated with disease progression, few biomarkers have been used to aid in disease diagnosis early in gestation. This review discusses the detection of oxidative stress markers in biological fluids and highlights the need for further studies to validate their use in the prediction or diagnosis of pregnancy disorders.

Correlation of Oxidative Stress Markers with Ultrasound and Cardiotocography Parameters with Hypertension Induced Pregnancy

Introduction:

Pregnancy induced hypertension (PIH), especially preeclampsia, is a state of extremely increased oxidative stress (OS), due to decrease of antioxidant capacity in comparison to normotensive pregnant women. The consequences of increased state of oxidative stress with hypertension disorder in pregnancy are disorder of placental blood flow, intrauterine hypoxia of the fetus and disturbance in transfer of O2 manifested as pathological ultrasound (US) parameters (amount of amniotic fluid and biophysical profile of fetus) and cardiotocography parameters (CTG).

Aim:

The aim of this research is to analyze correlation of TBARS oxidative stress markers with ultrasound parameters of pregnancy course and cardiotocography parameters in pregnant women with PIH.

Patients and methods:

Research has been performed at the Clinic of Gynecology and Obstetrics, University Clinical Centre of the Republic of Srpska. It covered 200 pregnant women, 100 of them with PIH and 100 healthy pregnant women, at gestational age from 28 to 40 weeks. All pregnant women were analyzed for US parameters of pregnancy course and CTG records as well as oxidative stress biomarker, values of Thiobarbituric Acid (TBARS).

Results:

Pregnant women with PIH had high statistical significant (pre)pathological CTG records and US- biophysical profile, less amount of amniotic fluid and delivered in lower gestation compared to healthy pregnant women. TBARS high values are statistical high significant frequent with pregnant women with PIH, who had pathological and pre-pathological biophysical profile and CTG records, as well as with US less amount of amniotic fluid (p<0.01). The highest TBARS values were presented with PIH pregnant women and US of less amount of amniotic fluid 42.3 µmol.

Conclusion:

There is statistical strong connection between TBARS values, being used as oxidative stress markers, and diagnostic methods used in PIH diagnostics, ultrasound (amount of amniotic fluid, fetus biophysical profile) and cardiotocography recording. TBARS could also be significant in clinical application for assessment of pregnant women with PIH in order to make decisions on pregnancy termination period.

The enigma ofin vivooxidative stress assessment: isoprostanes as an emerging target

Oxidative stress is believed to be one of the major factors behind several acute and chronic diseases, and may also be associated with ageing. Excess formation of free radicals in miscellaneous body environment may originate from endogenous response to cell injury, but also from exposure to a number of exogenous toxins. When the antioxidant defence system is overwhelmed, this leads to cell damage. However, the measurement of free radicals or their endproducts is tricky, since these compounds are reactive and short lived, and have diverse characteristics. Specific evidence for the involvement of free radicals in pathological situations has been difficult to obtain, partly owing to shortcomings in earlier described methods for the measurement of oxidative stress. Isoprostanes, which are prostaglandin-like bioactive compounds synthesized in vivo from oxidation of arachidonic acid, independently of cyclooxygenases, are involved in many human diseases, and their measurement therefore offers a way to assess oxidative stress. Elevated levels of F₂-isoprostanes have also been seen in the normal human pregnancy, but their physiological role has not yet been defined. Large amounts of bioactive F₂-isoprostanes are excreted in the urine in normal basal situations, with a wide interindividual variation. Their exact role in the regulation of normal physiological functions, however, needs to be explored further. Current understanding suggests that measurement of F₂-isoprostanes in body fluids provides a reliable analytical tool to study oxidative stress-related diseases and experimental inflammatory conditions, and also in the evaluation of various dietary antioxidants, as well as drugs with radical-scavenging properties. However, assessment of isoprostanes in plasma or urine does not necessarily reflect any specific tissue damage, nor does it provide information on the oxidation of lipids other than arachidonic acid.

The Unfolded Protein Response Regulates Uterine Myocyte Antioxidant Responsiveness During Pregnancy

There is considerable evidence that implicates oxidative stress in the pathophysiology of human pregnancy complications. However, the role and the mechanism of maintaining an antioxidant prosurvival uterine environment during normal pregnancy is largely unresolved. Herein we report that the highly active uterine unfolded protein response plays a key role in promoting antioxidant activity in the uterine myocyte across gestation. The unfolded protein response (UPR) senses the accumulation of misfolded proteins in the endoplasmic reticulum (ER) and activates a signaling network that consists of the transmembrane protein kinase eukaryotic translation initiation factor 2 alpha kinase 3/PKR-like-ER kinase (EIF2AK3), which acts to decrease protein translation levels, allowing for a lowered need for protein folding during periods of ER stress. However, independent of its translational regulatory capacity, EIF2AK3-dependent signals elicit the activation of the transcription factor, nuclear factor erythroid 2-like 2 (NFE2L2) in response to oxidative stress. NFE2L2 binds to antioxidant response elements in the promoters of a variety of antioxidant genes that minimize the opportunities for generation of reactive oxygen intermediates. Our analysis demonstrates that in the absence of EIF2AK3, the uterine myocyte experiences increased levels of reactive oxygen species due to decreased NFE2L2 activation. Elevated levels of intracellular reactive oxygen species were observed in the EIF2AK3 null cells, and this was associated with the onset of apoptotic cell death. These findings confirm the prosurvival and antioxidant role of UPR-mediated EIF2AK3 activation in the context of the human uterine myocyte.

The effect of n-3 LCPUFA supplementation on oxidative stress and inflammation in the placenta and maternal plasma during pregnancy

Pregnancy represents a state of heightened oxidative stress and inflammation, and these processes are further increased in pregnancy complications. The quality of the maternal diet is directly associated with maternal health and wellbeing, pregnancy and fetal outcomes, as well as the risk of pregnancy complications. Long chain polyunsaturated fatty acids (LCPUFAs) have significant potential to modify placental and fetal lipid environments and thereby modulate health outcomes. The omega-3 (n-3) LCPUFA in particular have been shown to exhibit both antioxidant and anti-inflammatory properties, and have potential therapeutic applications in reducing oxidative damage and inflammation during pregnancy. The purpose of this review is to provide an overview of our current understanding of the impact of maternal n-3 LCPUFA supplementation on oxidative stress and inflammation during pregnancy, with a particular focus on effects on the mother and the placenta.

"Cumulative Stress": The Effects of Maternal and Neonatal Oxidative Stress and Oxidative Stress-Inducible Genes on Programming of Atopy

Although extensive epidemiological and laboratory studies have been performed to identify the environmental and immunological causes of atopy, genetic predisposition seems to be the biggest risk factor for allergic diseases. The onset of atopic diseases may be the result of heritable changes of gene expression, without any alteration in DNA sequences occurring in response to early environmental stimuli. Findings suggest that the establishment of a peculiar epigenetic pattern may also be generated by oxidative stress (OS) and perpetuated by the activation of OS-related genes. Analyzing the role of maternal and neonatal oxidative stress and oxidative stress-inducible genes, the purpose of this review was to summarize what is known about the relationship between maternal and neonatal OS-related genes and the development of atopic diseases.

Acyl Chain Disorder and Azelaoyl Orientation in Lipid Membranes Containing Oxidized Lipids

Oxidized phospholipids occur naturally in conditions of oxidative stress and have been suggested to play an important role in a number of pathological conditions due to their effects on a lipid membrane acyl chain orientation, ordering, and permeability. Here we investigate the effect of the oxidized phospholipid 1-palmitoyl-2-azelaoyl-sn-glycero-3-phosphocholine (PazePC) on a model membrane of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) using a combination of (13)C-(1)H dipolar-recoupling nuclear magnetic resonance (NMR) experiments and united-atom molecular dynamics (MD) simulations. The obtained experimental order parameter SCH profiles show that the presence of 30 mol % PazePC in the bilayer significantly increases the gauche content of the POPC acyl chains, therefore decreasing the thickness of the bilayer, although with no stable bilayer pore formation. The MD simulations reproduce the disordering effect and indicate that the orientation of the azelaoyl chain is highly dependent on its protonation state with acyl chain reversal for fully deprotonated states and a parallel orientation along the interfacial plane for fully protonated states, deprotonated and protonated azelaoyl chains having negative and positive SCH profiles, respectively. Only fully or nearly fully protonated azelaoyl chain are observed in the (13)C-(1)H dipolar-recoupling NMR experiments. The experiments show positive SCH values for the azelaoyl segments confirming for the first time that oxidized chains with polar termini adopt a parallel orientation to the bilayer plane as predicted in MD simulations.

Serum Malondialdehyde Concentration and Glutathione Peroxidase Activity in a Longitudinal Study of Gestational Diabetes

Aims

The main goal of this study was to evaluate the presence of oxidative damage and to quantify its level in gestational diabetes.

Methods

Thirty-six healthy women and thirty-six women with gestational diabetes were studied in the three trimesters of pregnancy regarding their levels of oxidative stress markers. These women were diagnosed with diabetes in the second trimester of pregnancy. Blood glucose levels after 100g glucose tolerance test were higher than 190, 165 or 145 mg/dl, 1, 2 or 3 hours after glucose intake.

Results

The group of women with gestational diabetes had higher serum malondialdehyde levels, with significant differences between groups in the first and second trimester. The mean values of serum glutathione peroxidase activity in the diabetic women were significantly lower in the first trimester. In the group of women with gestational diabetes there was a negative linear correlation between serum malondialdehyde concentration and glutathione peroxidase activity in the second and third trimester.

Conclusions

In this observational and longitudinal study in pregnant women, the alterations attributable to oxidative stress were present before the biochemical detection of the HbA1c increase. Usual recommendations once GD is detected (adequate metabolic control, as well as any other normally proposed to these patients) lowered the concentration of malondialdehyde at the end of pregnancy to the same levels of the healthy controls. Serum glutathione peroxidase activity in women with gestational diabetes increased during the gestational period.

Superoxide dismutase activity and gene expression levels in Saudi women with recurrent miscarriage

The antioxidant activities of superoxide dismutase 1 (SOD1) and SOD2, as well as the levels of the oxidant superoxide anion (SOA) and the micronutrients zinc (Zn), copper (Cu) and manganese (Mn), were assayed in plasma, whole blood and placental tissue of non-pregnant (NP), healthy pregnant (HP) women and recurrent miscarriage (RM) patients. The results showed that SOD1 and SOD2 activities and the levels of Zn, Cu and Mn in plasma and whole blood of HP women were slightly, but significantly lower, and even more significantly decreased in RM patients compared to those observed in NP women (P<0.05 and P<0.0001, respectively). Additionally, whereas plasma SOD1 and SOD2 activities and Zn, Cu and Mn levels were significantly lower in RM patients, those of whole blood and placental tissue were significantly lower when compared to HP women (P<0.001 and P<0.0001, respectively). Concurrently, there were consistent increases of equal magnitude and statistical significance in SOA levels in all the assayed samples as identified by a comparison between the subjects. The findings thus supported oxidative metabolism and excessive reactive oxygen species generation. The resultant oxidative stress, identified in whole blood and placental tissues of RM patients, may have been a primary cause of RM. Dietary supplementation of Zn, Cu and Mn may be beneficial to these patients pre- and post-conception.

Potential Utility of Melatonin in Preeclampsia, Intrauterine Fetal Growth Retardation, and Perinatal Asphyxia

AIM

Reactive oxygen species play an important role in the pathogenesis of several diseases during gestation and the perinatal period. During pregnancy, increased oxygen demand augments the rate of production of free radicals. Oxidative stress is involved in pregnancy disorders including preeclampsia and intrauterine fetal growth retardation (IUGR). Moreover, increased levels of oxidative stress and reduced antioxidative capacities may contribute to the pathogenesis of perinatal asphyxia. Melatonin, an efficient antioxidant agent, diffuses through biological membranes easily and exerts pleiotropic actions on every cell and appears to be essential for successful gestation. This narrative review summarizes current knowledge concerning the role of melatonin in reducing complications during human pregnancy and in the perinatal period.

RESULTS

Melatonin levels are altered in women with abnormally functioning placentae during preeclampsia and IUGR. Short-term melatonin therapy is highly effective and safe in reducing complications during pregnancy and in the perinatal period. Because melatonin has been shown to be safe for both mother and fetus, it could be an attractive therapy in pregnancy and is considered a promising neuroprotective agent in perinatal asphyxia.

CONCLUSION

We believe that the use of melatonin treatment during the late fetal and early neonatal period might result in a wide range of health benefits, improved quality of life, and may help limit complications during the critical periods prior to, and shortly after, delivery.

Plasma F2-isoprostane class VI isomers at 12-18 weeks of pregnancy are associated with later occurrence of preeclampsia

Preeclampsia (PE) has long been associated with early oxidative stress, although the symptoms occur later in pregnancy. We have hypothesized that the oxidative stress in PE, as characterized by the presence of F2-isoprostane (F2-isoP) isomers in late pregnancy, should already be present in plasma at the first regular visit of the obstetrical follow-up. There are 64 possible isomers of F2-isoPs derived from the oxidation of arachidonic acid (AA), but only one of these isomers has been investigated so far in PE, the classical 8-iso-PGF2α. Here, we have investigated two regioisomers of class III (8-iso-15(R)-PGF2α and 8-iso-PGF2α) and a mix of two isomers of class VI ((±)5-iPF2α-VI) in plasma samples collected prospectively at 12-18 weeks from normotensive controls (n = 60) and pregnant mothers who developed PE later in pregnancy (n = 33). The plasma samples were subjected to alkaline hydrolysis followed by liquid-liquid extraction to extract total F2-isoPs for later quantification by HPLC-MS/MS. The F2-isoPs were normalized to either plasma volume or polyunsaturated fatty acid (PUFA) levels measured by GC-FID in plasma phospholipids. Early in pregnancy, only the class VI F2-isoP isomers were found at concentrations significantly higher in women developing PE later in pregnancy (+13%; p = 0.0074). Normalization of F2-isoPs to their substrate, AA, or the omega-3 to omega-6 ratio improved the predictability of PE as determined by receiver operating characteristic (from area under the curve of 0.67 to 0.68 and 0.70 respectively). Interestingly, omega-3 fatty acids were 25% higher in the control group than in the PE group (P = 0.0225). Omega-6 PUFAs correlated with F2-Isop isomers only in cases of PE (r > 0.377; P >0.03, Spearman correlation). In sum, this study indicates that specific isomers of class VI are significant predictors of PE. This work also suggests that F2-isoP isomers are not all generated and eliminated to the same extent and are influenced by the PUFA composition of plasma phospholipids.

A Proposed Molecular Mechanism of High-Dose Vitamin D3 Supplementation in Prevention and Treatment of Preeclampsia

A randomized prospective clinical study performed on a group of 74 pregnant women (43 presenting with severe preeclampsia) proved that urinary levels of 15-F(2t)-isoprostane were significantly higher in preeclamptic patients relative to the control (3.05 vs. 2.00 ng/mg creatinine). Surprisingly enough, plasma levels of 25-hydroxyvitamin D3 in both study groups were below the clinical reference range with no significant difference between the groups. In vitro study performed on isolated placental mitochondria and placental cell line showed that suicidal self-oxidation of cytochrome P450scc may lead to structural disintegration of heme, potentially contributing to enhancement of oxidative stress phenomena in the course of preeclampsia. As placental cytochrome P450scc pleiotropic activity is implicated in the metabolism of free radical mediated arachidonic acid derivatives as well as multiple Vitamin D3 hydroxylations and progesterone synthesis, we propose that Vitamin D3 might act as a competitive inhibitor of placental cytochrome P450scc preventing the production of lipid peroxides or excess progesterone synthesis, both of which may contribute to the etiopathogenesis of preeclampsia. The proposed molecular mechanism is in accord with the preliminary clinical observations on the surprisingly high efficacy of high-dose Vitamin D3 supplementation in prevention and treatment of preeclampsia.

F2-isoprostanes are correlated with trans fatty acids in the plasma of pregnant women

We hypothesized that the mild physiological oxidative stress present during pregnancy could increase both, plasma F2-isoprostanes (F2-isoPs) by lipid oxidation and trans fatty acids (TFA) through cis-trans isomerization respectively. Plasma samples collected at 12-18 weeks (MIROS cohort; n=65) and 38-41 weeks of pregnancy (CHUL cohort; n=21) were subjected to alkaline hydrolysis followed by liquid-liquid extraction in order to extract total F2-isoPs for quantification by HPLC-MS/MS. Several positive correlations were found between F2-isoPs and TFA, measured by GC-FID in plasma phospholipids, such as 6t-18:1, 9t-18:1 and 9t,12c-18:2 (r>0.306; p<0.045). Despite its low level, the 9t,12c-18:2 trans isomer, known to be associated to cardiovascular diseases, showed the most significant correlations with F2-isoPs. No correlation was observed between F2-isoPs and 9t-16:1 or 11t-18:1. In summary, this study suggests either a concomitant phenomenon or a competition between lipid peroxidation and cis-trans isomerisation of the cis precursor fatty acid in vivo during pregnancy.

Na⁺, K⁺-ATPase and Ca²⁺-ATPase activities in basal and microvillous syncytiotrophoblast membranes from preeclamptic human term placenta

OBJECTIVE

The aim of this study is to evaluate the effect of preeclampsia on the level of lipid peroxidation, activity and expression of both plasma membrane Ca(2+)- and Na(+), K(+)-ATPases in syncytiotrophoblast.

METHODS

The level of lipid peroxidation was estimated by measuring TBARS. ATPase activities were quantified by a colorimetric method measuring the amount of inorganic phosphate during the assay. Expression of Ca(2+)- and Na(+), K(+)-ATPases in syncytiotrophoblast plasma membranes and term placenta tissue sections was investigated using Western blot and immunohistochemistry, respectively.

RESULTS

Our results show a higher level of lipid peroxidation of syncytiotrophoblast plasma membranes from preeclamptic, as compared to uncomplicated pregnant women. Preeclampsia also significantly reduced the activity of Ca(2+)- and Na(+), K(+)-ATPases; however, expression of both ATPases was unaffected.

CONCLUSION

Our findings suggest that the reduction of Ca(2+)- and Na(+), K(+)-ATPase activities during preeclampsia could be at least partially due to an increased level of lipid peroxidation of the syncytiotrophoblast plasma membranes.

Oxidative stress markers in hypertensive states of pregnancy: preterm and term disease

Discussion continues as to whether de novo hypertension in pregnancy with significant proteinuria (pre-eclampsia; PE) and non-proteinuric new hypertension (gestational hypertension; GH) are parts of the same disease spectrum or represent different conditions. Non-pregnant hypertension, pregnancy and PE are all associated with oxidative stress. We have established a 6 weeks postpartum clinic for women who experienced a hypertensive pregnancy. We hypothesized that PE and GH could be distinguished by markers of oxidative stress; thiobarbituric acid reactive substances (TBARS) and antioxidants (ferric ion reducing ability of plasma; FRAP). Since the severity of PE and GH is greater pre-term, we also compared pre-term and term disease. Fifty-eight women had term PE, 23 pre-term PE, 60 had term GH and 6 pre-term GH, 11 pre-existing (essential) hypertension (EH) without PE. Limited data were available from normotensive pregnancies (n = 7) and non-pregnant controls (n = 14). There were no differences in postpartum TBARS or FRAP between hypertensive states; TBARS (P = 0.001) and FRAP (P = 0.009) were lower in plasma of non-pregnant controls compared to recently-pregnant women. Interestingly FRAP was higher in preterm than term GH (P = 0.013). In PE and GH, TBARS correlated with low density lipoprotein (LDL)-cholesterol (P = 0.036); this association strengthened with inclusion of EH (P = 0.011). The 10 year Framingham index for cardiovascular risk was positively associated with TBARS (P = 0.003). Oxidative stress profiles do not differ between hypertensive states but appear to distinguish between recently-pregnant and non-pregnant states. This suggests that pregnancy may alter vascular integrity with changes remaining 6 weeks postpartum. LDL-cholesterol is a known determinant of oxidative stress in cardiovascular disease and we have shown this association to be present in hypertensive pregnancy further emphasizing that such a pregnancy may be revealing a pre-existing cardiovascular risk.

Oxidative stress-mediated aging during the fetal and perinatal periods

Oxidative stress is worldwide recognized as a fundamental component of the aging, a process that begins before birth. There is a critical balance between free radical generation and antioxidant defenses. Oxidative stress is caused by an imbalance between the production of free radicals and the ability of antioxidant system to detoxify them. Oxidative stress can occur early in pregnancy and continue in the postnatal period; this damage is implicated in the pathophysiology of pregnancy-related disorders, including recurrent pregnancy loss, preeclampsia and preterm premature rupture of membranes. Moreover, diseases of the neonatal period such as bronchopulmonary dysplasia, retinopathy of prematurity, necrotizing enterocolitis, and periventricular leukomalacia are related to free radical damage. The specific contribution of oxidative stress to the pathogenesis and progression of these neonatal diseases is only partially understood. This review summarizes what is known about the role of oxidative stress in pregnancy and in the pathogenesis of common disorders of the newborn, as a component of the early aging process.

Does palm oil vitamin E reduce the risk of pregnancy induced hypertension?

In view of the high anti-oxidative potential oftocotrienol, the role of the tocotrienol-rich fraction (TRF) of palm oil in preventing pregnancy induced hypertension (PIH) was explored in a randomized double-blind placebo-controlled clinical trial in an urban teaching hospital. Healthy primigravidae were randomized to receive either oral TRF 100 mg daily or placebo, from early second trimester until delivery. Out of 299 women, 151 were randomized into the TRF arm and 148 into the placebo arm. A total of 15 (5.0%) developed PIH. Although there was no statistically significant difference in the incidence of PIH (4/151 or 2.6% in the TRF arm vs. 11/148 or 7.4% in the placebo arm, p = 0.058) between the two arms, there was a tendency towards a lower incidence of PIH in the TRF arm compared to the placebo arm. With TRF supplementation, the relative risk (RR) of PIH was 0.36 (95% CI 0.12-1.09). In conclusion, although TRF from palm oil does not statistically significantly reduce the risk of development of PIH in the population studied, the 64% reduction in incidence of PIH is substantial. The findings warrant further clinical trials, particularly in high risk populations.

Creatine supplementation during pregnancy: summary of experimental studies suggesting a treatment to improve fetal and neonatal morbidity and reduce mortality in high-risk human pregnancy

While the use of creatine in human pregnancy is yet to be fully evaluated, its long-term use in healthy adults appears to be safe, and its well documented neuroprotective properties have recently been extended by demonstrations that creatine improves cognitive function in normal and elderly people, and motor skills in sleep-deprived subjects. Creatine has many actions likely to benefit the fetus and newborn, because pregnancy is a state of heightened metabolic activity, and the placenta is a key source of free radicals of oxygen and nitrogen. The multiple benefits of supplementary creatine arise from the fact that the creatine-phosphocreatine [PCr] system has physiologically important roles that include maintenance of intracellular ATP and acid–base balance, post-ischaemic recovery of protein synthesis, cerebral vasodilation, antioxidant actions, and stabilisation of lipid membranes. In the brain, creatine not only reduces lipid peroxidation and improves cerebral perfusion, its interaction with the benzodiazepine site of the GABA_A receptor is likely to counteract the effects of glutamate excitotoxicity – actions that may protect the preterm and term fetal brain from the effects of birth hypoxia. In this review we discuss the development of creatine synthesis during fetal life, the transfer of creatine from mother to fetus, and propose that creatine supplementation during pregnancy may have benefits for the fetus and neonate whenever oxidative stress or feto-placental hypoxia arise, as in cases of fetal growth restriction, premature birth, or when parturition is delayed or complicated by oxygen deprivation of the newborn.

Recognition of malondialdehyde-modified proteins by the C terminus of complement factor H is mediated via the polyanion binding site and impaired by mutations found in atypical hemolytic uremic syndrome

Atypical hemolytic uremic syndrome (aHUS) is a severe thrombotic microangiopathy characterized by uncontrolled complement activation against endothelial and blood cells. Mutations in the C-terminal target recognition domains 19-20 of complement regulator factor H (FH) are strongly associated with aHUS, but the mechanisms triggering disease onset have remained unresolved. Here we report that several aHUS-related mutations alter the binding of FH19-20 to proteins where lysines have reacted with malondialdehyde (MDA). Although FH19-20 did not interact with MDA-modified hexylamine, lysine-containing peptides, or a proteolytically degraded protein, it bound to MDA-modified polylysine. This suggests that FH19-20 recognizes only clustered MDA adducts. Binding of MDA-modified BSA to FH19-20 was ionic by nature, depended on positive residues of FH19-20, and competed with the polyanions heparin and DNA. This could not be explained with the mainly neutral adducts known to form in MDA modification. When positive charges of lysines were eliminated by acetic anhydride instead of MDA, the acetylated BSA started to bind FH19-20. Together, these results indicate that negative charges on the modified proteins dominate the interaction with FH19-20. This is beneficial for the physiological function of FH because by binding to the negative charges of the modified target, FH could prevent excess complement activation initiated by naturally occurring antibodies recognizing MDA epitopes with multiple different structures. We propose that oxidative stress leading to formation of MDA adducts is a common feature for triggers of aHUS and that failure of FH in protecting MDA-modified surfaces from complement activation is involved in the pathogenesis of the disease.

Analysis of F2-isoprostanes in plasma of pregnant women by HPLC-MS/MS using a column packed with core-shell particles

Plasma F2-isoprostanes (F2-isoPs) are reliable biomarkers of oxidative stress. Several possible F2-isoPs are generated by the oxidation of arachidonic acid esterified in phospholipids. The separation of these isomers represents a technical challenge for rapid and selective determination. We have developed a HPLC-MS/MS method for the simultaneous determination of seven plasma F2-isoPs, namely 8-iso-15(R)-prostaglandin F2α (PGF2α), 8-iso-PGF2α, 15(R)-PGF2α, iPF2α-IV, iPF2α-VI, 5-iPF2α-VI, and (±)5-8,12-iso-iPF2α-VI. We have validated this method in plasma of pregnant women, a mild physiological oxidative stress known to increase F2-isoPs. Thus, plasma samples of women collected at the third trimester of pregnancy (n = 20) were subjected to alkaline hydrolysis followed by liquid-liquid extraction in order to extract total F2-isoPs. The F2-isoPs were separated within 16.5 min using a column packed with core-shell particles. The class VI isomers were the most abundant, accounting for 65% of the total level of all quantified F2-isoPs in plasma of pregnant women (P < 0.05). The 15(R)-PGF2α was the most abundant of the class III isomers quantified. This method allowed fast and selective separation of seven isomers from three different classes of F2-isoP regioisomers.