Oxidative stress and inflammatory markers in normal pregnancy and preeclampsia

Sepsis after middle cerebral artery occlusion exacerbates peripheral oxidative stress in a sex-specific manner

Ischemic stroke occurs due a blockage in the blood flow to the brain, leading to damage to the nervous system. The prevalent morbidities resulting from stroke include post-stroke infection, as sepsis. Additionally, oxidative stress is recognized for inducing functional deficits in peripheral organs during sepsis. Therefore, sex differences in stroke exist and we aimed to investigate the peripheral oxidative stress caused by sepsis after stroke in male and female rats. Wistar rats (male and female) were divided into sham+sham, middle cerebral artery occlusion (MCAO) + sham, sham+ cecal ligation and perforation (CLP) and MCAO+CLP groups to males and female rats. Animals were subjected to MCAO or sham and after 7 days, were subjected to sepsis by CLP or sham. After 24 h, serum, total brain, lung, liver, heart, and spleen were collected. Brain edema, myeloperoxidase (MPO) activity, nitrite/nitrate (N/N) concentration, oxidative damage to lipids and proteins, and catalase activity were evaluated. Brain edema was observed only in male rats in MCAO+CLP group compared to MCAO+sham. Regarding MPO activity, an increase was verified in male in different organs and serum in MCAO+CLP group. For N/N levels, the increase was more pronounced in females submitted to MCAO+CLP. In general, to oxidative stress, an increase was only observed in animals exposed to MCAO+CLP, or with a greater increase in this group compared to the others. The findings provided the first indication that animals exposed to MCAO exhibit a heightened vulnerability to the harmful impacts of sepsis, as evidenced by brain edema and peripheral oxidative stress, and this susceptibility is dependent of sex.

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.

The effect of gestational diabetes mellitus on carotid artery intima-media thickness in and after pregnancy: a systematic review and meta-analysis

AIMS

The association between gestational diabetes mellitus (GDM) and common carotid artery (CCA) intima-media thickness (IMT) is still controversial. This systematic review and meta-analysis was performed to assess the correlation between GDM and CCA-IMT in and after pregnancy.

METHODS

PubMed and EMBASE databases were systematically reviewed on April 2023. Studies measuring CCA-IMT in both pregnant women with GDM and women with previous history of GDM (pGDM) vs. healthy controls were included. The subtotal and overall standardized mean differences (SMDs) of CCA-IMT were calculated using the random-effect model.

RESULTS

Nineteen studies with a total of 302 GDM and 861 pGDM women were analyzed. The average value of CCA-IMT measured in GDM/pGDM (0.59 ± 0.12 mm) was slightly increased in comparison to the accepted reference limits of IMT according to age classes. Substantial heterogeneity was detected for the studies involving both GDM and pGDM women, with an overall statistic I2 of 86.0% (p < 0.001). Large SMDs were obtained for the studies conducted on both GDM and pGDM women, with an overall SMD of 0.89 (95%CI 0.63-1.15, p < 0.001). Egger's test for a regression intercept gave a p-value of 0.37, indicating no publication bias. On meta-regression analysis, all potential confounders (number of patients, age at pregnancy, body mass index, measuring time, follow-up duration and GDM criteria) were not significantly associated with effect modification.

CONCLUSIONS

GDM in and after pregnancy is independently associated with subclinical atherosclerosis. The association between GDM and carotid remodeling is potentially mediated by the longstanding underlying risk.

Characterization of the maternal serum inflammatory profile during pregnancy according to socioeconomic status

PROBLEM

In pregnancy, lower socioeconomic status (SES) is associated with adverse outcomes, which is partly attributed to chronic inflammation. Our study compared the maternal serum cytokine profiles in patients with low and high SES.

METHOD OF STUDY

This retrospective cohort study compared maternal serum cytokine profiles between Medicaid-insured patients who delivered at an urban safety-net hospital (low SES) and privately-insured patients who delivered at a community-based academic hospital (high SES) in Atlanta, GA (n = 32-33/group). Serum samples were obtained during prenatal venipuncture from 13 to 38 weeks' gestation and the cohorts were matched by gestational age. Interferon (IFN)-γ, Interleukin (IL)-10, IL-1β, IL-4, IL-6, IL-8, and Tumor Necrosis Factor (TNF)-α were assayed from maternal serum samples using a standard ELISA assay.

RESULTS

Median concentrations of IL-6, a promotor of chronic inflammation, were higher in the low SES group (0.85 vs. 0.49 pg/mL, p < .001), while median levels of IL-1β, a potent monocyte activator, and TNF-α, a master regulator of acute inflammation, were lower in the low SES group (0.09 vs. 0.46 pg/mL, p < .001, and 1.23 vs. 1.58 pg/mL, p = .002, respectively) as compared to the high SES group. After adjusting for maternal age, obesity, hypertensive disorders, and gestational age at delivery, the differences in IL-6 and IL-1β by SES persisted (p = .0002 and p < .0001, respectively).

CONCLUSIONS

In this retrospective cohort study, there were significant differences in levels of pro-inflammatory cytokines during pregnancy for groups defined by SES, even after adjustment for confounding variables. Our data are foundational for further research to investigate SES-associated inflammation that may contribute to adverse pregnancy outcomes.

Plasma levels of arginines at term pregnancy in relation to mode of onset of labor and mode of childbirth

PROBLEM

The exact biochemical mechanisms that initiate labor are not yet fully understood. Nitric oxide is a potent relaxant of uterine smooth muscles until labor starts, and its precursor is L-arginine. Asymmetric (ADMA) and symmetric (SDMA) dimethylarginines, are potent NO-inhibitors. However, arginines (dimethylarginines and L-arginine) are scarcely studied in relation to labor and childbirth. We aimed to investigate arginines in women with spontaneous (SLVB) and induced (ILVB) term labor with vaginal birth and in women undergoing elective caesarean section (ECS).

METHOD OF STUDY

Women at gestational week 16-18 were recruited to the population-based prospective cohort study BASIC at the Uppsala University Hospital, Sweden. Plasma samples taken at start of labor were analyzed for arginines, from SLVB (n = 45), ILVB (n = 45), and ECS (n = 45), using Ultra-High Performance Liquid Chromatography. Between-group differences were assessed using Kruskal-Wallis and Mann-Whitney U-test.

RESULTS

Women with SLVB and ILVB had higher levels of ADMA (p < .0001), SDMA (p < .05) and lower L-arginines (p < .01), L-arginine/ADMA (p < .0001), and L-arginine/SDMA (p < .01, respectively <.001) compared to ECS. However, ILVB had higher ADMA (p < .0001) and lower L-arginine (p < .01), L-arginine/ADMA (p < .0001), and L-arginine/SDMA (p < .01) compared to SLVB. Results are adjusted for gestational length at birth and cervical dilatation at sampling.

CONCLUSION

Our novel findings of higher levels of dimethylarginines in term vaginal births compared to ECS give insights into the biochemical mechanisms of labor. These findings might also serve as a basis for further studies of arginines in complicated pregnancies and labor.

Endothelial dysfunction in preterm infants: The hidden legacy of uteroplacental pathologies

Millions of infants are born prematurely every year worldwide. Prematurity, particularly at lower gestational ages, is associated with high mortality and morbidity and is a significant global health burden. Pregnancy complications and preterm birth syndrome strongly impact neonatal clinical phenotypes and outcomes. The vascular endothelium is a pivotal regulator of fetal growth and development. In recent years, the key role of uteroplacental pathologies impairing endothelial homeostasis is emerging. Conditions leading to very and extremely preterm birth can be classified into two main pathophysiological patterns or endotypes: infection/inflammation and dysfunctional placentation. The first is frequently related to chorioamnionitis, whereas the second is commonly associated with hypertensive disorders of pregnancy and fetal growth restriction. The nature, timing, and extent of prenatal noxa may alter fetal and neonatal endothelial phenotype and functions. Changes in the luminal surface, oxidative stress, growth factors imbalance, and dysregulation of permeability and vascular tone are the leading causes of endothelial dysfunction in preterm infants. However, the available evidence regarding endothelial physiology and damage is limited in neonates compared to adults. Herein, we discuss the current knowledge on endothelial dysfunction in the infectious/inflammatory and dysfunctional placentation endotypes of prematurity, summarizing their molecular features, available biomarkers, and clinical impact. Furthermore, knowledge gaps, shadows, and future research perspectives are highlighted.

Attenuation of baroreflex sensitivity and heart rate variability is linked to reduced levels of nitric oxide in pregnant women having risks of developing gestational hypertension

Purpose: Decreased baroreflex sensitivity (BRS) and sympathovagal imbalance (SVI) have been reported as a cardiovascular (CV) risk in gestational hypertension (GH). Nitric oxide (NO) has been implicated in pathophysiology of GH. In the present study, we assessed the link of CV risks (decreased BRS and SVI) to the plasma levels of NO in women having risk of developing GH. Materials and Methods: A total of 96 pregnant women having risk factors for GH were recruited for the study. The blood pressure variability (BPV), heart rate variability (HRV), plasma NO, marker of insulin resistance (HOMA-IR), lipid risk factors, inflammatory markers (hsCRP, interleukin-6), and malondialdehyde (MDA), the marker of oxidative stress (OS) were measured at 16^th and 36^th week. Link of various parameters to NO was assessed by correlation and multiple regression analysis. Results: Of HRV indices, parasympathetic components were decreased and sympathetic components were increased, BRS was decreased, NO was decreased, HOMA-IR, lipid risk factors, hsCRP, interleukin-6, and MDA were increased significantly at 36^th week compared to 16^th week of pregnancy. Most of the markers of cardiometabolic risk were correlated with NO. However, only the markers of CV risk (SVI and reduced BRS) were independently associated with decreased level of NO, but not the metabolic markers except interleukin-6. The independent contribution of BRS (β = 0.334, P < .001) to NO was found to be most significant. Conclusion: It was concluded that decreased BRS, SVI, and increased interleukin-6 are associated with reduction in NO in GH, which may possibly be linked to the development of CV risks in GH.

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.

Preeclamptic Women Have Decreased Circulating IL-10 (Interleukin-10) Values at the Time of Preeclampsia Diagnosis: Systematic Review and Meta-Analysis

A key immunomodulatory cytokine, IL-10 (interleukin-10), has been shown to be dysregulated in preeclampsia, a pregnancy-specific hypertensive disorder, further characterized by multi-system involvement. However, studies have reported inconsistent findings about circulating IL-10 levels in preeclamptic versus normotensive pregnancies. The aim of the present systematic review and meta-analysis was to assess circulating IL-10 levels in preeclamptic and normotensive pregnancies at 2 time points: before, and at the time of preeclampsia diagnosis. PubMED, EMBASE, and Web of Science databases were searched to include all published studies examining circulating IL-10 levels in preeclamptic and normotensive pregnancies. Differences in IL-10 levels were evaluated by standardized mean differences. Of 876 abstracts screened, 56 studies were included in the meta-analysis. Circulating IL-10 levels were not different before the time of active disease (standardized mean differences, -0.01 [95% CI, -0.11 to 0.08]; P=0.76). At the time of active disease, women with preeclampsia (n=1599) had significantly lower IL-10 levels compared with normotensive controls (n=1998; standardized mean differences, -0.79 [95% CI, -1.22 to -0.35]; P=0.0004). IL-10 levels were lower in both early/severe and late/mild forms of preeclampsia. Subgroup analysis revealed that IL-10 measurement methodology (ELISA or multiplex bead array) and the sample type (plasma or serum) significantly influenced the observed differences, with the use of sera paired with ELISA technology providing the best distinction in IL-10 levels between preeclamptic and normotensive pregnancies. These findings support the role of decreased IL-10 levels in the pathophysiology of preeclampsia. Future studies should address the therapeutic potential of IL-10 in preeclampsia.

Implication of Oxidative Stress in Fetal Programming of Cardiovascular Disease

Lifestyle and genetic background are well known risk factors of cardiovascular disease (CVD). A third contributing factor is suboptimal fetal development, due to nutrient or oxygen deprivation, placental insufficiency, or exposure to toxic substances. The fetus adapts to adverse intrauterine conditions to ensure survival; the immediate consequence is low birth weight (LBW) and the long-term effect is an increased susceptibility to develop CVD in adult life. This process is known as Developmental Origins of Health and Disease (DOHaD) or fetal programming of CVD. The influence of fetal life for the future cardiovascular health of the individual has been evidenced by numerous epidemiologic studies in populations suffering from starvation during intrauterine life. Furthermore, experimental animal models have provided support and enabled exploring the underlying mechanisms. Oxidative stress seems to play a central role in fetal programming of CVD, both in the response of the feto-placental unit to the suboptimal intrauterine environment and in the alterations of physiologic systems of cardiovascular control, ultimately leading to disease. This review aims to summarize current knowledge on the alterations in oxidative balance in response to fetal stress factors covering two aspects. Firstly, the evidence from human studies of the implication of oxidative stress in LBW induced by suboptimal conditions during intrauterine life, emphasizing the role of the placenta. In the second part we summarize data on specific redox alterations in key cardiovascular control organs induced by exposure to known stress factors in experimental animals and discuss the emerging role of the mitochondria.

Correlation of Plasma Neutrophil Elastase Activity and Endogenous Protease Inhibitor Levels with the Severity of Pre-eclampsia

INTRODUCTION

Pre-eclampsia (PE) is a common maternal syndrome characterized by severe systemic inflammatory response including neutrophil activation leading to uncontrolled activity of elastase. The excessive activity of elastase would lead to destroyal of the integrity of endothelial cells and could exacerbate the pathophysiological symptoms in PE. Thus, assessment of NE activity and its control mechanisms would be of relevance in the determination of severity of PE.

AIM

To correlate the activity of plasma NE and its endogenous inhibitors α₁-antitrypsin (α₁-AT) and α₂-macroglobulin (α₂-MG) with severity of PE.

MATERIALS AND METHODS

A comparative study was conducted between normotensive pregnant (n=50) and pre-eclamptic (n=50) women. Serum C-Reactive Protein (CRP) was estimated by rapid latex slide and uric acid by uricase method. Plasma elastase was estimated using succinyl tri- L-alanyl-p-nitroanilide as substrate. Plasma α₁-AT, α₂-MG and NE- α₁-AT complex were quantified by ELISA. ANOVA and Pearson's correlation tests were used to analyze the data. The results were expressed as mean±SD and p-value <0.001 was considered statistically highly significant.

RESULTS

The activity of elastase was increased significantly in severe PE (0.62±0.08) in comparison to normal (0.35±0.10) and mild pre-eclamptic subjects (0.37±0.03). The values of α₁-AT were significantly less in mild (83.94±25.08) and severe PE (68.58+26.39) in comparison to normal (110.26±42.39). There was a significant rise in the levels of α₂-MG in severe PE. However, the complex estimation did not evince any significant changes.

CONCLUSION

The results of the present study indicate a significantly elevated elastase activity, α₂-MG levels and decreased α₁-AT in severe PE patients. The correlation analyses of PE severity parameters with NE, α₁-AT and α₂-MG further support the roles of these molecules in the assessment of severity of PE.

Insulin Induces Relaxation and Decreases Hydrogen Peroxide-Induced Vasoconstriction in Human Placental Vascular Bed in a Mechanism Mediated by Calcium-Activated Potassium Channels and L-Arginine/Nitric Oxide Pathways

HIGHLIGHTS

Short-term incubation with insulin increases the L-arginine transport in HUVECs.

Short-term incubation with insulin increases the NO synthesis in HUVECs.

Insulin induces relaxation in human placental vascular bed.

Insulin attenuates the constriction induced by hydrogen peroxide in human placenta.

The relaxation induced by insulin is dependent on BKCa channels activity in human placenta.

Insulin induces relaxation in umbilical veins, increasing the expression of human amino acid transporter 1 (hCAT-1) and nitric oxide synthesis (NO) in human umbilical vein endothelial cells (HUVECs). Short-term effects of insulin on vasculature have been reported in healthy subjects and cell cultures; however, its mechanisms remain unknown. The aim of this study was to characterize the effect of acute incubation with insulin on the regulation of vascular tone of placental vasculature. HUVECs and chorionic vein rings were isolated from normal pregnancies. The effect of insulin on NO synthesis, L-arginine transport, and hCAT-1 abundance was measured in HUVECs. Isometric tension induced by U46619 (thromboxane A₂ analog) or hydrogen peroxide (H₂O₂) were measured in vessels previously incubated 30 min with insulin and/or the following pharmacological inhibitors: tetraethylammonium (KCa channels), iberiotoxin (BKCa channels), genistein (tyrosine kinases), and wortmannin (phosphatidylinositol 3-kinase). Insulin increases L-arginine transport and NO synthesis in HUVECs. In the placenta, this hormone caused relaxation of the chorionic vein, and reduced perfusion pressure in placental cotyledons. In vessels pre-incubated with insulin, the constriction evoked by H₂O₂ and U46619 was attenuated and the effect on H₂O₂-induced constriction was blocked with tetraethylammonium and iberiotoxin, but not with genistein, or wortmannin. Insulin rapidly dilates the placental vasculature through a mechanism involving activity of BKCa channels and L-arginine/NO pathway in endothelial cells. This phenomenon is related to quick increases of hCAT-1 abundance and higher capacity of endothelial cells to take up L-arginine and generate NO.

The Relationship of Restless Legs Syndrome to History of Pregnancy-Induced Hypertension

BACKGROUND

Restless legs syndrome (RLS), a burdensome sleep disorder, has been associated with cardiovascular disease (CVD), hypertension, diabetes, and related disorders. However, the relationship of RLS to history of pregnancy-induced hypertension (PIH), a predictor of subsequent CVD, diabetes, and associated conditions, remains little explored. In this study, we investigated the relationship of RLS to history of PIH in a sample of primary care patients.

METHODS

Participants were women aged ≥40 years drawn from an anonymous survey study of West Virginia primary care patients. Data collected included detailed information on demographics, lifestyle factors, sleep patterns, and reproductive/medical history; the survey also included an RLS diagnostic questionnaire. Women who were pregnant or unsure about their pregnancy status were excluded from the analyses.

RESULTS

Of the 498 participants in the final analytic sample, 24.5% met diagnostic criteria for RLS (17.9% with symptoms ≥once/week, 11.9% with symptoms ≥3 times/week); 73 (16.5% of parous women) reported a history of PIH, defined as physician-diagnosed preeclampsia or gestational hypertension. After adjustment for demographics, lifestyle characteristics, obesity, reproductive history, health conditions, and other factors, those reporting a history of PIH were approximately twice as likely to meet criteria for RLS (odds ratio [OR] = 1.9; 95% confidence interval [CI] = 1.1, 3.6). These associations increased in magnitude with increasing symptom frequency (adjusted OR for RLS with symptoms ≥3 times/week = 3.8; CI 1.9, 7.6; p for trend = 0.003).

CONCLUSIONS

History of PIH was strongly and positively related to current RLS in this study of primary care patients; these findings further support a possible role for metabolic dysregulation in RLS etiology.

Tryptophan metabolism, disposition and utilization in pregnancy

Tryptophan (Trp) requirements in pregnancy are several-fold: (1) the need for increased protein synthesis by mother and for fetal growth and development; (2) serotonin (5-HT) for signalling pathways; (3) kynurenic acid (KA) for neuronal protection; (4) quinolinic acid (QA) for NAD(+) synthesis (5) other kynurenines (Ks) for suppressing fetal rejection. These goals could not be achieved if maternal plasma [Trp] is depleted. Although plasma total (free + albumin-bound) Trp is decreased in pregnancy, free Trp is elevated. The above requirements are best expressed in terms of a Trp utilization concept. Briefly, Trp is utilized as follows: (1) In early and mid-pregnancy, emphasis is on increased maternal Trp availability to meet the demand for protein synthesis and fetal development, most probably mediated by maternal liver Trp 2,3-dioxygenase (TDO) inhibition by progesterone and oestrogens. (2) In mid- and late pregnancy, Trp availability is maintained and enhanced by the release of albumin-bound Trp by albumin depletion and non-esterified fatty acid (NEFA) elevation, leading to increased flux of Trp down the K pathway to elevate immunosuppressive Ks. An excessive release of free Trp could undermine pregnancy by abolishing T-cell suppression by Ks. Detailed assessment of parameters of Trp metabolism and disposition and related measures (free and total Trp, albumin, NEFA, K and its metabolites and pro- and anti-inflammatory cytokines in maternal blood and, where appropriate, placental and fetal material) in normal and abnormal pregnancies may establish missing gaps in our knowledge of the Trp status in pregnancy and help identify appropriate intervention strategies.

Sleep disorders in pregnancy and their association with pregnancy outcomes: a prospective observational study

PURPOSE

Sleep disturbances such as insomnia, nocturnal awakenings, restless legs syndrome, habitual snoring, and excessive daytime sleepiness are frequent during pregnancy, and these have been linked to adverse maternal and fetal outcomes.

METHODS

A prospective observational study was performed in high-risk Indian pregnant women. We used modified Berlin questionnaire (MBQ), Pittsburgh sleep quality index (PSQI), International Restless Legs Syndrome Study Group 2011 criteria, and Epworth sleepiness scale to diagnose various sleep disorders, such as symptomatic OSA, poor sleep quality and insomnia, RLS, and excessive daytime sleepiness, respectively, in successive trimesters of pregnancy. Outcome variables of interest were development of gestational hypertension (GH), gestational diabetes mellitus (GDM), and cesarean delivery (CS); the Apgar scores; and low birth weight (LBW). The relationship between sleep disorders and outcomes was explored using logistic regression analysis.

RESULTS

Outcome data were obtained in 209 deliveries. As compared to nonsnorers, women who reported snoring once, twice, and thrice or more had odds ratios for developing GH-4.0 (95 % CI 1.3-11.9), 1.5 (95 % CI 0.5-4.5), and 2.9 (95 % CI 1.0-8.2) and for undergoing CS-5.3 (95 % CI 1.7-16.3), 4.9 (95 % CI 1.8-13.1), and 5.1 (95 % CI 1.9-14.9), respectively. Pregnant women who were persistently positive on MBQ had increased odds for GH and CS.

CONCLUSIONS

Snoring and high-risk MBQ in pregnant women are strong risk factors for GH and CS. In view of the significant morbidity and health care costs, simple screening of pregnant women with questionnaires such as MBQ may have clinical utility.

A combined supplementation of omega-3 fatty acids and micronutrients (folic acid, vitamin B12) reduces oxidative stress markers in a rat model of pregnancy induced hypertension

Objectives

Our earlier studies have highlighted that an altered one carbon metabolism (vitamin B₁₂, folic acid, and docosahexaenoic acid) is associated with preeclampsia. Preeclampsia is also known to be associated with oxidative stress and inflammation. The current study examines whether maternal folic acid, vitamin B₁₂ and omega-3 fatty acid supplementation given either individually or in combination can ameliorate the oxidative stress markers in a rat model of pregnancy induced hypertension (PIH).

Materials and Methods

Pregnant Wistar rats were assigned to control and five treatment groups: PIH; PIH + vitamin B₁₂; PIH + folic acid; PIH + Omega-3 fatty acids and PIH + combined micronutrient supplementation (vitamin B₁₂ + folic acid + omega-3 fatty acids). L-Nitroarginine methylester (L-NAME; 50 mg/kg body weight/day) was used to induce hypertension during pregnancy. Blood Pressure (BP) was recorded during pregnancy and dams were dissected at d20 of gestation.

Results

Animals from the PIH group demonstrated higher (p<0.01 for both) systolic and diastolic BP; lower (p<0.01) pup weight; higher dam plasma homocysteine (p<0.05) and dam and offspring malondialdehyde (MDA) (p<0.01), lower (p<0.05) placental and offspring liver DHA and higher (p<0.01) tumor necrosis factor–alpha (TNF–ά) levels as compared to control. Individual micronutrient supplementation did not offer much benefit. In contrast, combined supplementation lowered systolic BP, homocysteine, MDA and placental TNF-ά levels in dams and liver MDA and protein carbonyl in the offspring as compared to PIH group.

Conclusion

Key constituents of one carbon cycle (folic acid, vitamin B₁₂ and DHA) may play a role in reducing oxidative stress and inflammation in preeclampsia.

The tryptophan utilization concept in pregnancy

The decrease in maternal plasma total (free + albumin-bound) tryptophan (Trp) during the third pregnancy trimester is attributed to induction of indoleamine 2,3-dioxygenase (IDO). When measured, free [Trp] is increased because of albumin depletion and non-esterified fatty acid elevation. The Trp depletion concept in pregnancy is therefore not supported because of incorrect interpretation of changes in Trp disposition and also for not addressing mouse strain differences in Trp-related responses and potential inhibition of Trp transport by the IDO inhibitor 1-methyl tryptophan. Application of the Trp utilization concept in pregnancy offers several physiological advantages favoring fetal development and successful outcome, namely provision of Trp for fetal protein synthesis and growth, serotonin for signaling pathways, kynurenic acid for neuroprotection, quinolinic acid for NAD⁺ synthesis, and other kynurenines for suppression of T cell responses. An excessive increase in Trp availability could compromise pregnancy by undermining T cell suppression, e.g., in pre-eclampsia.

The relationship of hypovitaminosis D and IL-6 in preeclampsia

OBJECTIVE

Vitamin D deficiency has been linked to the pathogenesis of preeclampsia. Given the demonstrated antiinflammatory function of vitamin D in multiple organ systems including trophoblast cells and placenta, we hypothesized that vitamin D deficiency contributes to the development of preeclampsia through increased inflammation, as indicated by elevated interleukin (IL)-6 concentrations.

STUDY DESIGN

Plasma samples from a large preeclampsia cohort study were examined in 100 preeclamptic and 100 normotensive pregnant women. Comparisons of vitamin D and IL-6 concentrations used Student t test and χ(2) test or their nonparametric counterparts. A logistic regression model assessed the association among vitamin D, IL-6 concentrations, and preeclampsia risk.

RESULTS

The mean concentration of 25-hydroxyvitamin D was 49.4 ± 22.6 nmol/L in normotensives and 42.3 ± 17.3 nmol/L in preeclamptic women (P = .01). The median (interquartile range: Q1, Q3) concentrations of IL-6 were 2.0 (1.3, 3.4) pg/mL and 4.4 (2.2, 10.0) pg/mL in the control and preeclampsia groups, respectively (P < .01). We observed a significant association between IL-6 elevation and preeclampsia (odds ratio, 4.4; 95% confidence interval, 1.8-10.8; P < .01) and between vitamin D deficiency and preeclampsia (odds ratio, 4.2; 95% confidence interval, 1.4-12.8; P = .04). However, there was no association between vitamin D deficiency and IL-6 elevation.

CONCLUSION

Third-trimester IL-6 elevation and vitamin D deficiency were independently associated with the risk of preeclampsia. We found no evidence to support the hypothesis that vitamin D deficiency alters the pathogenesis of preeclampsia by activation of inflammation as assessed by IL-6 concentration.

Prepregnancy Vascular Dysfunction in Women who Subsequently Develop Hypertension During Pregnancy

OBJECTIVE

To evaluate vascular dysfunction using both physiologic measures and biochemical markers, longitudinally, prior to and during pregnancy, in nulliparous women who had uncomplicated pregnancies compared to those who developed complicated hypertension during pregnancy.

METHODS

Twenty healthy nulliparous women were studied during the follicular phase and in early (EP) and late (LP) pregnancy. All had singleton conceptions and delivered at term, seventeen with uncomplicated pregnancies (NP) and three who developed complicated hypertension (HP) after the LP evaluation. We compared prepregnancy, EP and LP pulse wave velocity (PWV) and soluble vascular cell adhesion molecule (sVCAM-1) between the NP and HP groups. PWV was measured using ultrasound and simultaneous echocardiogram tracing then calculated as the estimated distance divided by interval between EKG r-wave peak and peak brachial artery flow. SVCAM-1 was measured using a commercially available kit. Data are means ± SE, significance accepted as p < 0.05.

RESULTS

The NP group had significantly lower prepregnant PWV (NP: 2.66 ± 0.06 m/s, HP: 3.00 ± 0.04, p=.02), but PWV was not different at the EP or LP time points. SVCAM-1 was significantly lower prior to pregnancy and during EP and LP in the NP group (Prepregnancy: NP: 712 ± 32 ng/mL, HP: 1058 ± 107, p < .001; EP: NP: 695 ± 31 ng/mL, HP: 924 ± 52, p = .004; LP: NP: 663 ± 25 ng/mL, HP: 946 ± 36, p < .001).

CONCLUSIONS

PWV and sVCAM-1 may be important prepregnancy discriminators useful in assessing risk for preeclampsia prior to pregnancy.

Preeclampsia and Sleep-Disordered Breathing: A Case-Control Study

OBJECTIVE

To determine whether sleep-disordered breathing (SDB) is more prevalent among women with preeclampsia than among normotensive controls.

STUDY DESIGN

Preeclamptic patients admitted to the hospital for observation and normotensive, gestational age matched controls hospitalized for obstetrical indications other than preeclampsia were recruited for an overnight sleep evaluation. Watch-PAT100, a validated wrist-mounted, ambulatory device designed to diagnose SDB, was used to complete all sleep studies.

RESULTS

Twenty preeclamptic patients and 20 controls were recruited. Preeclamptic subjects had a higher mean BMI (32.6± 9.5 vs. 24.5 ± 3.5, P=0.001). Preeclamptic subjects had higher mean respiratory disturbance (RDI, mean difference 4.9 events/hour of sleep), apnea hypopnea (AHI, mean difference 5.7 events/hour of sleep) and oxygen desaturation (ODI, mean difference 4.5 events/hour of sleep) indices, however these differences did not reach statistical significance. Preeclamptic subjects were more likely to have more severe forms of SDB compared to controls (ODI ≥ 5, 20% vs. 0%, p=.047).

CONCLUSION

Compared to normotensive controls, preeclamptic subjects experience more SDB events and a greater degree of nocturnal hypoxemia. Further research is needed to determine if SBD, independent of BMI, is a significant contributing factor to the risk of developing preeclampsia.

RAS in Pregnancy and Preeclampsia and Eclampsia

Preeclampsia is a common disease of pregnancy characterized by the presence of hypertension and commitment of many organs, including the brain, secondary to generalized endothelial dysfunction. Its etiology is not known precisely, but it involved several factors, highlighting the renin angiotensin system (RAS), which would have an important role in the origin of multisystem involvement. This paper reviews the evidence supporting the involvement of RAS in triggering the disease, in addition to the components of this system that would be involved and how it eventually produces brain engagement.

In utero oxidative stress epigenetically programs antioxidant defense capacity and adulthood diseases

SIGNIFICANCE

Maternal health and diet during gestation are critical for predicting fetal outcomes, both immediately at birth and in adulthood. While epigenetic modifications have previously been tightly linked to carcinogenesis, recent advances in the field have suggested that numerous adulthood diseases, including those characteristic of metabolic syndrome, could be programmed in utero in response to maternal exposures, and these "programmable" diseases are associated with epigenetic modifications of vital genes.

RECENT ADVANCES

While little is currently known about the epigenetic regulation of the antioxidant (AOX) defense system, several studies in animals show that AOX defense capacity may be programmed in utero, making it likely that the critical genes involved in this pathway are epigenetically regulated, either by DNA methylation or by the modification of histone tails.

CRITICAL ISSUES

This article presents the most current knowledge of the in utero regulation of the AOX defense capacity, and will specifically focus on the potential epigenetic regulation of this system in response to various in utero exposures or stimuli. The ability to appropriately respond to oxidative stress is critical for the health and survival of any organism, and the potential programming of this capacity may provide a link between the in utero environment and the tendency of certain individuals to be more susceptible toward disease stimuli in their postnatal environments.

FUTURE DIRECTIONS

We sincerely hope that future studies which result in a deeper understanding of the in utero programming of the epigenome will lead to novel and effective therapies for the treatment of epigenetically linked diseases.

Oxidative damage, inflammation, and Toll-like receptor 4 pathway are increased in preeclamptic patients: a case-control study

Problem. There was no direct correlation between plasma and placental oxidative damage parameters and inflammation and evidence of TLR4 pathway activation in the placenta in preeclamptic (PE) patients. Method of Study. 33 PE patients and 33 normotensive pregnant women were included. The maternal section of the placenta and blood were collected to the determination of oxidative damage markers (thiobarbituric acid reactive species and protein carbonyls), inflammatory response (interleukin-6 and myeloperoxidase activity), and activation of the TLR-4-NF-kB pathway. Results. An increase of IL-6 levels in both plasma and placenta was observed, but myeloperoxidase activity was not significantly different comparing the groups. Oxidative damage parameters were increased in plasma and placenta in PE patients. A significant increase of the protein levels of TLR-4 and NF-kB was observed in the placenta. Conclusion. The TLR4-NF-kB pathway is upregulated in PE, probably generating local and systemic inflammatory response that is followed by local and systemic oxidative damage.

Inflammatory disturbances in preeclampsia: relationship between maternal and umbilical cord blood

Preeclampsia (PE) is one of the main causes of maternal and fetal mortality and morbidity. PE is associated with an inflammatory state and with oxidative stress, in maternal circulation. Our aim was to evaluate and compare the levels of oxidative stress and inflammatory markers in maternal and umbilical cord blood (UCB), in normal and PE pregnancies. We measured acute-phase proteins (CRP and α1-antitrypsin), proinflammatory cytokines (IL-6 and TNF-α), leukocyte activation (elastase, lactoferrin, sL-selectin, sVCAM, sPECAM), total antioxidant status (TAS), thiobarbituric acid reactive substances (TBARS), and uric acid levels. We studied 42 healthy pregnant women, 46 PE women, and their neonates. The concentrations of IL-6, TNF-α, α1-antitrypsin, CRP, sVCAM, uric acid, and TBARS were significantly higher, and sL-selectin was significantly lower in PE pregnant women as compared with normotensive pregnant women. In newborns uric acid, α1-antitrypsin, and CRP values were significantly higher in PE; leukocyte count, sL-selectin, lactoferrin, and the ratio elastase/α1-antitrypsin were significantly lower. Our data suggest that PE pregnancy is associated with an enhanced maternal inflammatory condition, which is reflected in fetal circulation. This enhanced inflammatory state seems to be related to endothelial dysfunction and increased cytokine synthesis, rather than with neutrophil activation.

Implication of low level inflammation in the insulin resistance of adipose tissue at late pregnancy

Insulin resistance is a characteristic of late pregnancy, and adipose tissue is one of the tissues that most actively contributes to the reduced maternal insulin sensitivity. There is evidence that pregnancy is a condition of moderate inflammation, although the physiological role of this low-grade inflammation remains unclear. The present study was designed to validate whether low-grade inflammation plays a role in the development of insulin resistance in adipose tissue during late pregnancy. To this end, we analyzed proinflammatory adipokines and kinases in lumbar adipose tissue of nonpregnant and late pregnant rats at d 18 and 20 of gestation. We found that circulating and tissue levels of adipokines, such as IL-1β, plasminogen activator inhibitor-1, and TNF-α, were increased at late pregnancy, which correlated with insulin resistance. The observed increase in adipokines coincided with an enhanced activation of p38 MAPK in adipose tissue. Treatment of pregnant rats with the p38 MAPK inhibitor SB 202190 increased insulin-stimulated tyrosine phosphorylation of the insulin receptor (IR) and IR substrate-1 in adipose tissue, which was paralleled by a reduction of IR substrate-1 serine phosphorylation and an enhancement of the metabolic actions of insulin. These results indicate that activation of p38 MAPK in adipose tissue contributes to adipose tissue insulin resistance at late pregnancy. Furthermore, the results of the present study support the hypothesis that physiological low-grade inflammation in the maternal organism is relevant to the development of pregnancy-associated insulin resistance.

Psychiatric symptoms and proinflammatory cytokines in pregnancy

OBJECTIVE

Clinical studies suggest that psychiatric symptoms, particularly depression, anxiety, and trauma, may be associated with inflammation, as indexed by proinflammatory cytokines. Such a link may be especially significant in pregnancy and may shed additional light on the etiology of perinatal mood disorders.

METHODS

We prospectively observed 145 women selected from a community obstetric clinic serving a primarily low-income, high-psychosocial risk population. Women without evidence of medical high-risk pregnancies were screened (including psychiatric and trauma histories) and then assessed in detail (e.g., mood symptoms) at approximately 18 and 32 weeks' gestation. Blood was drawn to measure key proinflammatory markers, interleukin 6 and tumor necrosis factor α (TNF-α). Data on pregnancy and obstetric outcome were derived from medical records.

RESULTS

There was considerable stability of cytokine levels within individuals and a significant mean increase across pregnancy observed for interleukin 6 (p < .001) and TNF-α (p < .001). History of trauma was associated with significantly elevated TNF-α levels (F(1,135) = 4.43, p < .05), controlling for psychosocial and obstetric covariates. In contrast, elevated measures of depression and anxiety were unrelated to proinflammatory cytokines (p > .1). Exploratory analyses indicated that neither psychiatric symptoms nor proinflammatory cytokines predicted birth weight, gestational age, or obstetric complications.

CONCLUSIONS

These findings suggest that antecedent trauma may be associated with persistently elevated TNF-α levels during pregnancy. The evidence that a generalized proinflammatory state was associated with symptoms of depression or anxiety in pregnant women was not found.

Serum level and antioxidant activity of ceruloplasmin in preeclampsia

The antioxidants activities are decreased in the serum of women with preeclampsia. This study was aimed to determine the serum level and antioxidant activity of ceruloplasmin in preeclamptic women with gestational age over than 28 weeks. In a cross-sectional and descriptive-analytic study performed on 60 patients with preeclampsia (30 with mild and 30 with severe preeclampsia) and 30 women with normal pregnancy (control) in Tabriz al-Zahra Hospital, serum level and antioxidant activity of ceruloplasmin was evaluated. The mean gestational age was 32.94+/-2.79 week in mild preeclampsia group, 32.17+/-3.00 week in severe preeclampsia group and 32.46+/-4.04 week in control group (p = 0.821). The mean serum level of ceruloplasmin was 0.62+/-0.16 g L-1 in mild preeclampsia group, 0.61+/-0.23 g L-1 in severe preeclampsia group and 0.47+/-0.16 g L-1 in control group. The serum ceruloplasmin in control group was significantly lower (p = 0.006). The mean antioxidant activity of ceruloplasmin was 562.54+/-139.79 in mild preeclampsia group, 556.21+/-190.94 in severe preeclampsia group and 427.62+/-162.14 in control group. The antioxidant activity was measured as production of mg dL-1 of a colored product. The antioxidant activity of ceruloplasmin in control group patients was significantly lower (p = 0.002). Significant linear positive correlation was found between serum level of ceruloplasmin and antioxidant activity of ceruloplasmin (p<0.001 and r = 0.910). Serum level of ceruloplasmin is significantly lower in normal pregnancy than mild and severe preeclampsia. Antioxidant activity of ceruloplasmin is significantly lower in normal pregnancy than mild and severe preeclampsia.

Nrf2 induces interleukin-6 (IL-6) expression via an antioxidant response element within the IL-6 promoter

IL-6 gene expression is controlled by a promoter region containing multiple regulatory elements such as NF-κB, NF-IL6, CRE, GRE, and TRE. In this study, we demonstrated that TRE, found within the IL-6 promoter, is embedded in a functional antioxidant response element (ARE) matching an entire ARE consensus sequence. Further, point mutations of the ARE consensus sequence in the IL-6 promoter construct selectively eliminate ARE but not TRE activity. Nrf2 is a redox-sensitive transcription factor which provides cytoprotection against electrophilic and oxidative stress and is the most potent activator of ARE-dependent transcription. Using Nrf2 knock-out mice we demonstrate that Nrf2 is a potent activator of IL-6 gene transcription in vivo. Moreover, we show evidence that Nrf2 is the transcription factor that activates IL6 expression in a cholestatic hepatitis mouse model. Our findings suggest a possible role of IL-6 in oxidative stress defense and also give indication about an important function for Nrf2 in the regulation of hematopoietic and inflammatory processes.

Impact of oxidative stress on female fertility

PURPOSE OF REVIEW

To review the role of oxidative stress in the context of female fertility.

RECENT FINDINGS

Oxidative stress is associated with decreased female fertility in animal and in-vitro models, but no studies to date have directly assessed the relationship in women. Exposures associated with oxidative stress and with evidence to influence the timing and maintenance of a viable pregnancy include pregnancy complications (e.g. preeclampsia), extremes of body weight, alcohol, tobacco, and caffeine intake. Intake of antioxidant nutrients, including use of multivitamins, impacts the generation of reactive oxygen species and may play a beneficial role in female fertility.

SUMMARY

Infertility is a significant public health problem and diagnosis and treatment are stressful, invasive, and costly. The role of oxidative stress in female fertility is an understudied and compelling area for investigation. Identifying modifiable factors to decrease oxidative stress in the gynecologic environment may be an inexpensive and noninvasive therapy for increasing fertility.