Maternal and fetal plasma adenosine deaminase, xanthine oxidase and malondialdehyde levels in pre-eclampsia

Longitudinal Assessment of Oxidative Stress Markers in Women with Preeclampsia

Preeclampsia (PE) is a pregnancy-specific disorder and a major contributor to maternal and fetal morbidity and mortality. Role of oxidative stress in early pregnancy with the pathophysiology of the disorder is unclear. The current study aims to analyse maternal levels of oxidative stress markers (MDA and protein carbonyl) longitudinally across gestation and placental levels of oxidative stress markers (MDA, protein carbonyl and 8-oxo-2'-deoxyguanosine) in women with PE and compare them with non-PE women. 324 pregnant women (216 non-PE and 108 PE women) were longitudinally followed during pregnancy. Women with preeclampsia were stratified as early onset preeclampsia (EOP) and late onset preeclampsia (LOP) Maternal blood at four time points across gestation (11-14 weeks, 18-22 weeks, 26-28 weeks, and at delivery) and placenta were collected. Maternal and placental levels of oxidative stress markers were assessed using commercially available kits. Maternal plasma MDA and protein carbonyl levels were comparable between the PE and non-PE group at all timepoints across gestation. Maternal plasma MDA were significantly higher levels at 26-28 weeks in EOP women when compared to non-PE women (p < 0.05). Placental 8-oxo-dG levels were lower in the EOP group as compared to non-PE (p < 0.05). Elevated plasma MDA levels were positively associated with birth length at 18-22 weeks and 26-28 weeks in the PE group (p < 0.05 for both). Maternal plasma MDA levels were positively associated with systolic blood pressure at 18-22 weeks. Oxidative stress in early pregnancy is not associated with risk of PE.

The Nitrate-Nitrite-Nitric Oxide Pathway: Potential Role in Mitigating Oxidative Stress in Hypertensive Disorders of Pregnancy

Hypertensive diseases of pregnancy (HDPs) represent a global clinical challenge, affecting 5-10% of women and leading to complications for both maternal well-being and fetal development. At the heart of these complications is endothelial dysfunction, with oxidative stress emerging as a pivotal causative factor. The reduction in nitric oxide (NO) bioavailability is a vital indicator of this dysfunction, culminating in blood pressure dysregulation. In the therapeutic context, although antihypertensive medications are commonly used, they come with inherent concerns related to maternal-fetal safety, and a percentage of women do not respond to these therapies. Therefore, alternative strategies that directly address the pathophysiology of HDPs are required. This article focuses on the potential of the nitrate-nitrite-NO pathway, abundantly present in dark leafy greens and beetroot, as an alternative approach to treating HDPs. The objective of this review is to discuss the prospective antioxidant role of nitrate. We hope our discussion paves the way for using nitrate to improve endothelial dysfunction and control oxidative stress, offering a potential therapy for managing HDPs.

Serum uric acid did not affect embryonic and pregnancy outcomes in women without PCOS during IVF procedures

Objectives

Serum uric acid (UA) levels are associated with many systemic diseases. A previous study confirmed the association between high serum uric acid levels and poor prognosis of in vitro fertilization (IVF) treatment in polycystic ovary syndrome (PCOS) patients. This study aimed to explore the correlation between serum uric acid levels and reproductive outcomes in patients without PCOS.

Methods

A retrospective study that included 1057 patients who underwent pre-implantation genetic testing for monogenic disorders (PGT-M) treatment from January 2013 to December 2020 was conducted. The study population was further divided into 3 groups according to serum UA levels: the ≤250 μmol/L group, the 251-360 μmol/L group, and the >360 μmol/L group. The controlled ovarian hyperstimulation (COH) treatment outcomes, embryonic treatment outcomes and pregnancy outcomes of the first frozen embryo transfer (FET) cycle were compared among groups. Multivariable linear regression and binary regression were applied to detect the association between IVF outcomes and serum uric acid levels.

Results

The number of retrieved oocytes, fertilization rate, viable embryo rate, blastocyst formation rate and euploid rate were not associated with serum uric acid levels. The mature oocyte rate was negatively correlated with serum uric acid levels. The pregnancy outcomes of the first FET cycle were also not associated with serum uric acid levels. After adjustment for BMI, the perinatal outcomes were not associated with serum uric acid levels.

Conclusion

IVF treatment outcomes were not associated with serum uric acid levels in patients without PCOS.

Association of Umbilical Cord Serum Oxidative Stress Markers, ADMA and Adiponectin with Adverse Fetal Outcomes in Hypertensive Disorders of Pregnancy

BACKGROUND

Limited studies are available on fetal oxidative stress and endothelial dysfunction and their association with adverse fetal outcomes in hypertensive disorders of pregnancy (HDP). Method: Umbilical cord blood samples were collected at delivery from 134 pregnant women with HDP and 59 controls. Markers of oxidative stress, endothelial dysfunction and inflammation and adipokines were analyzed. Results were correlated with adverse fetal outcomes. Results: Malondialdehyde, total antioxidant status(TAS), ADMA and hsCRP levels were increased in late and early onset preeclampsia. Adiponectin levels were decreased in early onset preeclampsia. High ADMA levels were positively associated with preterm births and fetal mortality and high TAS, protein carbonyl content(PC), ADMA and low adiponectin levels were positively associated with low birth weight babies. Conclusion: Fetal systemic oxidative stress, endothelial dysfunction and inflammation were altered in early and late onset preeclampsia. High TAS, PC and ADMA levels and low adiponectin levels were positively associated with adverse fetal outcomes in HDP.

Serum uric acid levels associated with biochemical parameters linked to preeclampsia severity and to adverse perinatal outcomes

AIMS

Evaluating the association between serum uric acid levels and biochemical parameters linked to preeclampsia (PE) severity and to adverse perinatal outcomes.

METHODS

Cross-sectional study. Information about gestational and biochemical parameters were collected before delivery, whereas perinatal outcomes were observed after it. Pregnant women were divided into hyperuricemia-HU (uric acid ≥ 6 mg/dL) or normouricemia (uric acid, 2.6-5.9 mg/dL) groups. Poisson regression models (prevalence ratio-PR; 95% confidence interval-95% CI), multinomial logistic regression (odds ratio-OR; 95% CI), and Pearson's correlation (correlation coefficient-r) were applied by taking into consideration p < 0.05 as significance level.

RESULTS

The total sample comprised 267 pregnant women with PE. HU was observed in 25.8% of patients; it was associated with black pregnant women (p = 0.014) and with primiparity (p = 0.007). Uric acid levels were higher in early PE cases than in late PE cases (p = 0.013); however, there was no significant difference between mild and severe PE cases (p = 0.121). Uric acid recorded a positive correlation to urea (p < 0.001), creatinine (p = 0.002), glutamic-oxaloacetic transaminase (p < 0.001), glutamic-pyruvic transaminase (p = 0.005), ferritin (p = 0.002) and globulin (p = 0.002); as well as negative correlation to platelets (p = 0.035), lactic dehydrogenase (p = 0.039) and albumin (p > 0.001). HU was a factor associated with cesarean delivery (p = 0.030), prematurity (p = 0.001), low birth weight (p < 0.001) and small for gestational age (p = 0.020).

CONCLUSION

High serum uric acid levels were associated with early-onset PE. Maternal features were correlated to biochemical parameters linked to PE severity and to adverse perinatal outcomes.

Plasma Adenosine Deaminase (ADA)-1 and -2 Demonstrate Robust Ontogeny Across the First Four Months of Human Life

Background

Human adenosine deaminases (ADAs) modulate the immune response: ADA1 via metabolizing adenosine, a purine metabolite that inhibits pro-inflammatory and Th1 cytokine production, and the multi-functional ADA2, by enhancing T-cell proliferation and monocyte differentiation. Newborns are relatively deficient in ADA1 resulting in elevated plasma adenosine concentrations and a Th2/anti-inflammatory bias compared to adults. Despite the growing recognition of the role of ADAs in immune regulation, little is known about the ontogeny of ADA concentrations.

Methods

In a subgroup of the EPIC002-study, clinical data and plasma samples were collected from 540 Gambian infants at four time-points: day of birth; first week of life; one month of age; and four months of age. Concentrations of total extracellular ADA, ADA1, and ADA2 were measured by chromogenic assay and evaluated in relation to clinical data. Plasma cytokines/chemokine were measured across the first week of life and correlated to ADA concentrations.

Results

ADA2 demonstrated a steady rise across the first months of life, while ADA1 concentration significantly decreased 0.79-fold across the first week then increased 1.4-fold by four months of life. Males demonstrated significantly higher concentrations of ADA2 (1.1-fold) than females at four months; newborns with early-term (37 to <39 weeks) and late-term (≥41 weeks) gestational age demonstrated significantly higher ADA1 at birth (1.1-fold), and those born to mothers with advanced maternal age (≥35 years) had lower plasma concentrations of ADA2 at one month (0.93-fold). Plasma ADA1 concentrations were positively correlated with plasma CXCL8 during the first week of life, while ADA2 concentrations correlated positively with TNFα, IFNγ and CXCL10, and negatively with IL-6 and CXCL8.

Conclusions

The ratio of plasma ADA2/ADA1 concentration increased during the first week of life, after which both ADA1 and ADA2 increased across the first four months of life suggesting a gradual development of Th1/Th2 balanced immunity. Furthermore, ADA1 and ADA2 were positively correlated with cytokines/chemokines during the first week of life. Overall, ADA isoforms demonstrate robust ontogeny in newborns and infants but further mechanistic studies are needed to clarify their roles in early life immune development and the correlations with sex, gestational age, and maternal age that were observed.

Expression of plasma nuclear factor-kappa B cells (NF-κB) and Inhibitory subunit kappa B alpha (IκB-α) in HIV-associated pre-eclampsia

Objective:To investigate the expression of plasma NF-κB and the inhibitory subunit IκB-α in HIV-associated pre-eclampsia. Method: This retrospective study examined plasma NF-κB and IκB-α expression expressed as Mean Fluorescence Intensity (MFI) in normotensive (n = 32) and pre-eclamptic (n = 34) pregnant women stratified by HIV status. Results: A significant decrease in the level of plasma NF-κB expression between pre-eclamptic and normotensive pregnant women was observed, irrespective of HIV status (MFI = 82.8 vs 134.3; p = 0.03). Similarly, a significant decline in the level of plasma IκB-α expression was noted in the pre-eclamptic compared to normotensive pregnant women, irrespective of HIV status (MFI = 91.2 vs 120.1; p = 0.04). Plasma NF-κB (p = 0.7) and IκB-α (p = 0.8) expression was similar between HIV positive and HIV negative pregnant women, irrespective of pregnancy type. Conclusion: This study demonstrates decreased plasma NF-κB and IκB-α expression in preeclampsia compared to normotensive pregnant women irrespective of HIV status.

Oxidative Stress and Preeclampsia-Associated Prothrombotic State

Preeclampsia (PE) is a common obstetric disease characterized by hypertension, proteinuria, and multi-system dysfunction. It endangers both maternal and fetal health. Although hemostasis is critical for preventing bleeding complications during pregnancy, delivery, and post-partum, PE patients often develop a severe prothrombotic state, potentially resulting in life-threatening thrombosis and thromboembolism. The cause of this thrombotic complication is multi-factorial, involving endothelial cells, platelets, adhesive ligands, coagulation, and fibrinolysis. Increasing evidence has shown that hemostatic cells and factors undergo oxidative modifications during the systemic inflammation found in PE patients. However, it is largely unknown how these oxidative modifications of hemostasis contribute to development of the PE-associated prothrombotic state. This knowledge gap has significantly hindered the development of predictive markers, preventive measures, and therapeutic agents to protect women during pregnancy. Here we summarize reports in the literature regarding the effects of oxidative stress and antioxidants on systemic hemostasis, with emphasis on the condition of PE.

Variation of genes involved in oxidative and nitrosative stresses in depression

The dominating hypothesis among numerous hypotheses explaining the pathogenesis of depressive disorders (DD) is the one involving oxidative and nitrosative stress. In this study, we examined the association between single-nucleotide polymorphisms of the genes encoding SOD2 (superoxide dismutase 2), CAT (catalase), GPx4 (glutathione peroxidase 4), NOS1 (nitric oxide synthase 1), NOS2 (nitric oxide synthase 2), and the development of depressive disorders. Our study was carried out on the DNA isolated from peripheral blood collected from 281 depressed patients and 229 controls. Using TaqMan probes, we genotyped the following six polymorphisms: c.47T>C (p.Val16Ala) (rs4880) in SOD2, c.-89A>T (rs7943316) in CAT, c.660T>C (rs713041) in GPx4, c.-420-34221G>A (rs1879417) in NOS1, c.1823C>T (p.Ser608Leu) (rs2297518), and c.-227G>C (rs10459953) in NOS2. We found that the T/T genotype of the c.47T>C polymorphism was linked with an increased risk of depression. Moreover, the T/T genotype and T allele of c.660T>C increased the risk of DD occurrence, while the heterozygote and C allele decreased this risk. On the other hand, we discovered that the A/A genotype of c.-89A>T SNP was associated with a reduced risk of DD, while the A/T genotype increased this risk. We did not find any correlation between the genotypes/alleles of c.-420-34221G>A, c.1823C>T, and c.-227G>C, and the occurrence of DD. In addition, gene-gene and haplotype analyses revealed that combined genotypes and haplotypes were connected with the disease. Moreover, we found that sex influenced the impact of some SNPs on the risk of depression. Concluding, the studied polymorphisms of SOD2, CAT and GPx4 may modulate the risk of depression. These results support the hypothesis that oxidative and nitrosative stresses are involved in the pathogenesis of depressive disorders.

The Guanine-Based Purinergic System: The Tale of An Orphan Neuromodulation

Guanine-based purines (GBPs) have been recently proposed to be not only metabolic agents but also extracellular signaling molecules that regulate important functions in the central nervous system. In such way, GBPs-mediated neuroprotection, behavioral responses and neuronal plasticity have been broadly described in the literature. However, while a number of these functions (i.e., GBPs neurothophic effects) have been well-established, the molecular mechanisms behind these GBPs-dependent effects are still unknown. Furthermore, no plasma membrane receptors for GBPs have been described so far, thus GBPs are still considered orphan neuromodulators. Interestingly, an intricate and controversial functional interplay between GBPs effects and adenosine receptors activity has been recently described, thus triggering the hypothesis that GBPs mechanism of action might somehow involve adenosine receptors. Here, we review recent data describing the GBPs role in the brain. We focus on the involvement of GBPs regulating neuronal plasticity, and on the new hypothesis based on putative GBPs receptors. Overall, we expect to shed some light on the GBPs world since although these molecules might represent excellent candidates for certain neurological diseases management, the lack of putative GBPs receptors precludes any high throughput screening intent for the search of effective GBPs-based drugs.

Is Xanthine Oxidase, a Marker in Pre-eclampsia? A Case-Control Study

INTRODUCTION

Pre-eclampsia is an obstetrics problem that affects multiple systemic functions and leads to the increased maternal and fetal morbidity and mortality. The objective of the study was to evaluate the plasma levels of Xanthine oxidase (XO) activity, uric acid and Nitric oxide (NO) levels in women with pre-eclampsia and normal pregnancy during antenatal and postpartum period.

MATERIALS AND METHODS

A case control study was conducted in women with normal pregnancy (n=50) and pre-eclampsia (n=50) before and after delivery. XO activity, uric acid and NO levels were determined from samples at 30-39 weeks of gestation. The current study was conducted in association with Obstetrics and Gynecology Department of R.L. Jalappa Hospital and Research Center. The blood samples were analysed for assay of XO, uric acid and NO. The results were analysed by using SPSS software version 2013. P-value < 0.05 was considered as statistically significant.

RESULTS

The plasma XO activity was elevated (p<0.001) in the pre-eclampsia compared to normotensive pregnant women before delivery and decreased after delivery (p<0.001) significantly. Uric acid level showed a significant increase in pre-eclampsia when compared to the control before delivery (p<0.001) however values were non-significant after delivery.

CONCLUSION

Placenta plays a key role in the pathophysiology of pre-eclampsia. Placenta removal leads to decrease trend of xanthine oxidase activity, uric acid and elevation of Nitric oxide as reversible changes in pre-eclampsia patients within 48 hours after delivery.

The relationship between hypertension and plasma allantoin, uric acid, xanthine oxidase activity and nitrite, and their predictive capacity in severe preeclampsia

It is controversial that uric acid (UA) levels are related to the severity of hypertension in preeclampsia (PE). Our aim in this study was to determine whether UA, xanthine oxidase activity (XOA), allantoin and nitrite levels are related to arterial blood pressure (BP) in PE. We formed a control group (n = 20) and a PE group (n = 20) for the study. Their BPs and plasma UA, XOA, allantoin and nitrite levels were measured. The values from the control and PE pregnant women were assessed via a Wilcoxon matched-pairs test. A Pearson correlation test was also performed. In addition, the diagnostic value of these tests was evaluated via receiver operating characteristic (ROC) analysis. The BP, UA, XOA and allantoin levels in the PE patients were found to be higher when compared with those of the pregnant controls. The UA, XOA and allantoin levels showed high correlations with BP in cases of PE. However, there was no superiority among the correlations. No differences were observed between the groups in terms of nitrite levels and the relationship between nitrite and BP. UA, XOA and allantoin levels may be high due to placental cell death because of abnormal trophoblastic activity observed in PE. Moreover, the reactive oxygen products that are created during the genetic material degradation may explain how UA, XOA and allantoin levels are related to BP. According to ROC analysis, UA, XOA and allantoin assays are reliable predictors for the determination of PE.

Purinergic transmission in blood vessels

There are nineteen different receptor proteins for adenosine, adenine and uridine nucleotides, and nucleotide sugars, belonging to three families of G protein-coupled adenosine and P2Y receptors, and ionotropic P2X receptors. The majority are functionally expressed in blood vessels, as purinergic receptors in perivascular nerves, smooth muscle and endothelial cells, and roles in regulation of vascular contractility, immune function and growth have been identified. The endogenous ligands for purine receptors, ATP, ADP, UTP, UDP and adenosine, can be released from different cell types within the vasculature, as well as from circulating blood cells, including erythrocytes and platelets. Many purine receptors can be activated by two or more of the endogenous ligands. Further complexity arises because of interconversion between ligands, notably adenosine formation from the metabolism of ATP, leading to complex integrated responses through activation of different subtypes of purine receptors. The enzymes responsible for this conversion, ectonucleotidases, are present on the surface of smooth muscle and endothelial cells, and may be coreleased with neurotransmitters from nerves. What selectivity there is for the actions of purines/pyrimidines comes from differential expression of their receptors within the vasculature. P2X1 receptors mediate the vasocontractile actions of ATP released as a neurotransmitter with noradrenaline (NA) from sympathetic perivascular nerves, and are located on the vascular smooth muscle adjacent to the nerve varicosities, the sites of neurotransmitter release. The relative contribution of ATP and NA as functional cotransmitters varies with species, type and size of blood vessel, neuronal firing pattern, the tone/pressure of the blood vessel, and in ageing and disease. ATP is also a neurotransmitter in non-adrenergic non-cholinergic perivascular nerves and mediates vasorelaxation via smooth muscle P2Y-like receptors. ATP and adenosine can act as neuromodulators, with the most robust evidence being for prejunctional inhibition of neurotransmission via A1 adenosine receptors, but also prejunctional excitation and inhibition of neurotransmission via P2X and P2Y receptors, respectively. P2Y2, P2Y4 and P2Y6 receptors expressed on the vascular smooth muscle are coupled to vasocontraction, and may have a role in pathophysiological conditions, when purines are released from damaged cells, or when there is damage to the protective barrier that is the endothelium. Adenosine is released during hypoxia to increase blood flow via vasodilator A2A and A2B receptors expressed on the endothelium and smooth muscle. ATP is released from endothelial cells during hypoxia and shear stress and can act at P2Y and P2X4 receptors expressed on the endothelium to increase local blood flow. Activation of endothelial purine receptors leads to the release of nitric oxide, hyperpolarising factors and prostacyclin, which inhibits platelet aggregation and thus ensures patent blood flow. Vascular purine receptors also regulate endothelial and smooth muscle growth, and inflammation, and thus are involved in the underlying processes of a number of cardiovascular diseases.

Purinergic signaling and blood vessels in health and disease

Purinergic signaling plays important roles in control of vascular tone and remodeling. There is dual control of vascular tone by ATP released as a cotransmitter with noradrenaline from perivascular sympathetic nerves to cause vasoconstriction via P2X1 receptors, whereas ATP released from endothelial cells in response to changes in blood flow (producing shear stress) or hypoxia acts on P2X and P2Y receptors on endothelial cells to produce nitric oxide and endothelium-derived hyperpolarizing factor, which dilates vessels. ATP is also released from sensory-motor nerves during antidromic reflex activity to produce relaxation of some blood vessels. In this review, we stress the differences in neural and endothelial factors in purinergic control of different blood vessels. The long-term (trophic) actions of purine and pyrimidine nucleosides and nucleotides in promoting migration and proliferation of both vascular smooth muscle and endothelial cells via P1 and P2Y receptors during angiogenesis and vessel remodeling during restenosis after angioplasty are described. The pathophysiology of blood vessels and therapeutic potential of purinergic agents in diseases, including hypertension, atherosclerosis, ischemia, thrombosis and stroke, diabetes, and migraine, is discussed.

Adenosine deaminase activity in normal pregnancy and pregnancy associated disorders

Adenosine deaminase (ADA) is an enzyme of purine salvage pathway and has two important isoenzymes ADA1 and ADA2. The activity of ADA has been changed in diseases characterized by altered cell-mediated immunity. It was observed that total serum ADA activity was decreased during normal pregnancy compared with non-pregnant women. However, total serum ADA activity and serum ADA2 activity was increased in hyperemesis gravidarum and pre-eclampsia in pregnant women. Less information is available regarding role of ADA in abortions (recurrent and missed) and anembryonic pregnancies. Here, we review the activity of ADA and its isoenzymes. Despite these findings, it will be interesting to know whether activity of ADA will be same if ADA is estimated throughout the pregnancy and in pregnancy related complications from early first trimester to third trimester, as all studies until now were carried out at a particular stage of pregnancy.

Total oxidant, antioxidant, and paraoxonase levels in babies born to pre-eclamptic mothers

AIM

The aim of this study was to investigate the oxidant-antioxidant status in babies born to pre-eclamptic mothers (BBPM).

MATERIAL AND METHODS

The paraoxonase (PON)-1, total antioxidant status (TAS), and total oxidant status (TOS) levels were measured in the cord blood and venous blood (7th day) of BBPM (n = 31) and babies born to normotensive mothers (n = 25).

RESULTS

The PON-1 and TOS levels in the cord blood and venous blood on the 7th day were not significantly different between the two groups; however, the cord blood TAS levels were higher in BBPM (P = 0.001), and the TAS levels in the venous blood were higher in the control group (P = 0.021). Furthermore, the cord blood PON-1 levels of babies born to severely pre-eclamptic mothers (n = 18) were higher than those of babies born to moderately pre-eclamptic mothers (n = 13) (P = 0.042). There were no differences in the cord blood TAS and TOS levels and venous blood PON-1, TAS, and TOS levels between babies born to severely and moderately pre-eclamptic mothers.

CONCLUSION

The increased TAS levels found in the cord blood of BBPM indicate that the fetus is protected against oxidative damage caused by increased oxidative stress in the mother. To the best of our knowledge, this is the first study in the published work investigating PON-1 levels in BBPM.

Impaired A2A adenosine receptor/nitric oxide/VEGF signaling pathway in fetal endothelium during late- and early-onset preeclampsia

To investigate whether fetal endothelial cell proliferation and migration are modulated by the A2A adenosine receptor (A2AAR), nitric oxide (NO) and the vascular endothelial growth factor (VEGF) signaling pathway, we isolated human umbilical vein endothelial cells from normal pregnancy (n = 23), preterm delivery (n = 4), and late-onset (LOPE, n = 10) and early-onset preeclampsia (EOPE, n = 8). We used the non-selective adenosine receptor agonist (NECA) and the selective agonist (CGS-21680) and/or selective antagonist (ZM-241385) for A2AAR. Also, the nitric oxide synthase (NOS) inhibitor, L-NAME, was used in co-incubation with CGS-21680. Compared to normal pregnancy, EOPE exhibited low cell proliferation and migration associated with reduced expressions of A2AAR and VEGF and NO synthesis (i.e., total and phosphorylated serine(1177) endothelial NOS and nitrite formation). In contrast, LOPE exhibited the opposite behavior in all these markers compared to normal pregnancy or EOPE. Cell proliferation and migration were increased by CGS-21680 (or NECA) in all analyzed groups (EOPE>LOPE>normal pregnancy) compared to their respective basal conditions, an effect that was associated with high NO and VEGF synthesis and blocked by ZM-241385 with significantly different IC50 for each group (EOPE>LOPE>normal pregnancy). The differences seem independent of gestational age. L-NAME blocked the CGS-21680-mediated cell proliferation and migration in normal pregnancy and LOPE (IC50 = 36.2 ± 2.5 and 8.6 ± 2.2 nM, respectively) as well as the VEGF expression in normal pregnancy. Therefore, the A2AAR/NO/VEGF signaling pathway exhibits a pro-angiogenic effect in normal pregnancies and LOPE, whereas impairment in this pathway seems related to the reduced angiogenic capacity of the fetal endothelium in EOPE.

Maternal and fetal plasma platelet-activating factor acetylhydrolase activity and distribution in pre-eclampsia

BACKGROUND

Distribution of platelet-activating factor acetylhydrolase (PAF-AH) in lipoproteins plays important roles in the onset of inflammation and atherosclerosis. We hypothesized that women with pre-eclampsia (PE), showing signs of inflammation and oxidative stress, and their fetuses have aberrations of PAF-AH activity and distribution.

METHODS

Maternal and fetal plasma PAF-AH activity, high-density lipoprotein (HDL)-associated PAF-AH (H-PAF-AH) and low-density lipoprotein (LDL)-associated PAF-AH (L-PAF-AH) were examined in women with PE (n = 127) and in women with uncomplicated pregnancies (n = 88).

RESULTS

The neonates of women with severe PE (n = 42) had significantly higher plasma PAF-AH, L-PAF-AH activities, and ratio of L-PAF-AH to H-PAF-AH activities than the neonates of women with normal pregnancies (n = 83). The mothers with severe PE (n = 106) and their neonates presented a significantly higher atherogenic index (AI) and triglyceride (TG)/HDL cholesterol (C) ratio than the control mothers and their neonates. The ratio of L-PAF-AH to H-PAF-AH activities correlated positively with TG levels, TG/HDL(C) ratio, and AI and negatively with HDL(C) levels in the neonates of women with PE.

CONCLUSION

The neonates of women with severe PE presented with a chronic inflammation status, increased oxidative stress, and unfavorable lipid changes, which may potentially link to related complications responsible for oxidative stress and inflammation in later life.

Adenosine A₂a receptors and O₂ sensing in development

Reduced mitochondrial oxidative phosphorylation, via activation of adenylate kinase and the resulting exponential rise in the cellular AMP/ATP ratio, appears to be a critical factor underlying O₂ sensing in many chemoreceptive tissues in mammals. The elevated AMP/ATP ratio, in turn, activates key enzymes that are involved in physiologic adjustments that tend to balance ATP supply and demand. An example is the conversion of AMP to adenosine via 5'-nucleotidase and the resulting activation of adenosine A(₂A) receptors, which are involved in acute oxygen sensing by both carotid bodies and the brain. In fetal sheep, A(₂A) receptors associated with carotid bodies trigger hypoxic cardiovascular chemoreflexes, while central A(₂A) receptors mediate hypoxic inhibition of breathing and rapid eye movements. A(₂A) receptors are also involved in hypoxic regulation of fetal endocrine systems, metabolism, and vascular tone. In developing lambs, A(₂A) receptors play virtually no role in O₂ sensing by the carotid bodies, but brain A(₂A) receptors remain critically involved in the roll-off ventilatory response to hypoxia. In adult mammals, A(₂A) receptors have been implicated in O₂ sensing by carotid glomus cells, while central A(₂A) receptors likely blunt hypoxic hyperventilation. In conclusion, A(₂A) receptors are crucially involved in the transduction mechanisms of O₂ sensing in fetal carotid bodies and brains. Postnatally, central A(₂A) receptors remain key mediators of hypoxic respiratory depression, but they are less critical for O₂ sensing in carotid chemoreceptors, particularly in developing lambs.

Early left ventricular diastolic dysfunction in premature infants born to preeclamptic mothers

AIM

To evaluate the cardiac function in premature infants born to preeclamptic mothers and its clinical consequences.

METHODS

This was a prospective observational cohort study performed in a tertiary neonatal intensive care unit. Fifty-three premature infants born to preeclamptic mothers comprising the study group were evaluated and compared with 42 premature infants born to normotensive mothers (control group). Relationship between echocardiographic measures and neonatal morbidity were assessed as the main outcome measures.

RESULTS

Left ventricle end-diastolic dimension (LVEDD), peak flow velocities during early diastole (peak E wave), peak flow velocities during atrial contraction (peak A wave), and peak E/A ratio were significantly lower in the study group. Within the study group, these parameters were also significantly lower in infants with respiratory problems. LVEDD was significantly smaller in preeclamptic infants with intrauterine growth retardation (IUGR).

CONCLUSION

Left ventricle diastolic dysfunction (LVDD) was detected in premature infants born to preeclamptic mothers in the first week after delivery. LVDD was associated with higher incidence of respiratory problems, transient tachypnea of the newborn, longer duration of oxygen requirement, and IUGR.

Pathological aspects of lipid peroxidation

Lipid peroxidation (LPO) product accumulation in human tissues is a major cause of tissular and cellular dysfunction that plays a major role in ageing and most age-related and oxidative stress-related diseases. The current evidence for the implication of LPO in pathological processes is discussed in this review. New data and literature review are provided evaluating the role of LPO in the pathophysiology of ageing and classically oxidative stress-linked diseases, such as neurodegenerative diseases, diabetes and atherosclerosis (the main cause of cardiovascular complications). Striking evidences implicating LPO in foetal vascular dysfunction occurring in pre-eclampsia, in renal and liver diseases, as well as their role as cause and consequence to cancer development are addressed.

Expression of AT1R, AT2R and AT4R and their roles in extravillous trophoblast invasion in the human

The placental renin-angiotensin system (RAS) is active from early pregnancy and may have a role in placentation. Angiotensin II (AngII) acts via binding to receptor types AT1R and AT2R. Recently smaller peptide members of the angiotensin family have been recognised as having biological relevance. Angiotensin (3-8) (AngIV) has a specific receptor (AT4R) and evokes hypertrophy, vasodilatation and vascular inflammatory response. The aim of this study was to characterise placental expression of AT1R, AT2R and AT4R, and to determine whether AngII and AngIV regulate extravillous trophoblast (EVT) invasion, apoptosis and proliferation. Placental samples were obtained from women undergoing elective surgical termination of pregnancy (TOP) at 8-10 weeks gestation (early TOP), 12-14 weeks gestation (mid TOP) or at delivery following normal pregnancy or with pre-eclampsia (PE). Immunohistochemistry and qRT-PCR were performed to determine placental mRNA and protein expression of AT1R, AT2R and AT4R at all gestational ages. EVT invasion following culture with AngII or AngIV was assessed in early placental tissue using Matrigel invasion assays. Invasion was assessed on day 6 of culture and placental explants were harvested for immunohistochemical analysis of apoptosis and proliferation. The results from qRT-PCR and immunohistochemistry showed placental AT1R expression which did not vary with gestation. The highest levels of expression of AT2R were found in early and mid TOP placentae compared to term pregnancy. Expression of AT4R was increased in term placentae, with a significant reduction in PE placentae. Moreover, culture with AngIV or AngII increased EVT invasion from placental explants, which showed increased trophoblast proliferation and reduced apoptosis. This study has characterised expression of AT4R and AT1R and AT2R in human placenta throughout normal pregnancy and in PE. Both AngIV and AngII may play an important role in normal pregnancy.

Increased xanthine oxidase in the thalamus and putamen in depression

A growing body of literature suggests persistent and selective structural changes in the cortico-limbic-thalamic-striatal system in patients with recurrent depressive disorder (DD). Oxidative stress is thought to play a key role in these processes. So far, the main scientific focus has been on antioxidant enzymes in this context. For the first time, this proof of concept study examines the activity of the free radicals producing the enzyme, xanthine oxidase (XO), directly in the cortico-limbic-thalamic-striatal system of patients with recurrent depression. The activity of XO was ascertained in the cortico-limbic-thalamic-striatal regions in post-mortem brain tissue of patients with recurrent depressive episodes and individuals without any neurological or psychiatric history (7/7). We measured the XO activity in following brain areas: hippocampus, regio entorhinalis, thalamus, putamen and caudate nucleus. In this study, we report a significant increase of XO activity in the thalamus and the putamen of patients with depression. Our findings contribute to the growing body of evidence suggesting that oxidative stress plays a pivotal role in certain brain areas in recurrent depressive disorder.

Malondialdehyde and Antioxidant Enzymes in Maternal and Cord Blood, and their Correlation in Normotensive and Preeclamptic Women

Background

An increased oxidative level and decreased antioxidant activities in the blood of preeclamptic women have been reported by us and other workers. The present study was aimed to evaluate oxidative stress in infants born to preeclamptic mothers, and to examine whether cord blood with oxygen radical disease had different total enzymatic antioxidant status than those without preeclampsia.

Methods

The present study consisted of 23 normotensive (served as control) and 23 preeclamptic mothers. We compared their oxidative and anti-oxidative system in maternal and cord blood of pair-matched mother and neonate. Their blood malondialdehyde (MDA), antioxidant enzymes were determined and compared to evaluate if pro-oxidative status of preeclampsia differs from the status in cord blood of pair-matched neonate.

Results

The MDA content in preeclamptic maternal plasma was significantly high (p < 0.001) compared to that of control. Interestingly, its content in preeclamptic cord blood was significantly low (p < 0.001) compared to their pair-matched maternal blood. Superoxide dismutase (SOD) activity was 8.7% higher in cord as compared to pair-matched normotensive maternal blood which was significant (p = 0.01) whereas in preeclamptic cord the level decreased significantly (p = 0.011) in comparison to pair-matched preeclamptic maternal. Glutathione peroxidase (GPx) was 16.4% higher in normotensive cord compared to maternal blood, and 7% low in preeclamptic cord compared to pair-matched maternal blood. The increase was significant (P = 0.011) in normotensive cord whereas in preeclamptic cord the decrease was insignificant (p = 0.06). Contrary to earlier reports on catalase activity, our results showed 20.97% elevation in normotensive and 16.12% increase in the preeclamptic cord blood compared to their pair-matched maternal blood. This change was significant with p = 0.01 and p = 0.017 in control and preeclamptic group respectively.

Conclusions

Our results showed the significantly low MDA contents in the pair-matched cord blood and the activities of SOD, GPx and Catalase mentioned above, we conclude that the oxidative stress status is low in the blood of neonates born to preeclamptic mothers. Further studies are needed to explore strategies so that the normal levels of antioxidant vitamins are maintained to combat preeclampsia in women at high risk.

Keywords

Maternal; Cord blood; Malondialdehyde; Antioxidant enzymes; Glutathione peroxidase; Glutathione reductase; Superoxide dismutase; Catalase

Increased xanthine oxidase in the skin of preeclamptic women

Xanthine oxioreductase is the holoenzyme responsible for terminal purine catabolism. Under conditions of metabolic stress or heightened proinflammatory cytokine production, this enzyme is preferentially in its oxidized form, xanthine oxidase, with catalytic action that generates uric acid and the free radical superoxide. As preeclampsia is characterized by heightened inflammation, oxidative stress, and hyperuricemia, it has been proposed that xanthine oxidase plays a pivotal role in this hypertensive disorder of pregnancy. We sought to determine whether xanthine oxidase protein content was higher in maternal tissue of preeclamptic mothers, compared to healthy pregnant controls, using immunohistochemical analysis of skin biopsies. We further compared xanthine oxidase immunoreactivity in skin biopsies from preeclamptic women and patients with several inflammatory conditions. In preeclamptic women, intense xanthine oxidase immunoreactivity was present within the epidermis. By contrast, only very faint xanthine oxidase staining was observed in skin biopsies from healthy pregnant controls. Further, a role for inflammation in the increase of xanthine oxidase was suggested by similar findings of heightened xanthine oxidase immunoreactivity in the skin biopsies from nonpregnant individuals diagnosed with conditions of systemic inflammation. The finding of increased xanthine oxidase in maternal tissue, most likely as the result of heightened maternal inflammation, suggests maternal xanthine oxidase as a source of free radical and uric acid generation in preeclampsia.

Lung maturation in small for gestational age fetuses from pregnancies complicated by placental insufficiency or maternal hypertension

BACKGROUND

Clinical studies suggest that respiratory outcome of infants born preterm may be influenced by placental insufficiency and hemolysis, elevated liver enzymes, low platelets (HELLP) syndrome. If so, one could expect to see differences in lung maturation indices (lecithin/sphingomyelin (L/S) ratio and lamellar body count (LBC)) in the amniotic fluid. The present study investigates lung maturation indices of preterm small for gestational age (SGA) fetuses with or without abnormal Doppler ultrasound examination and with or without maternal hypertension/HELLP syndrome.

STUDY DESIGN

Retrospective cohort study of 76 neonates born in our center between 1997 and 2003 with gestational age (GA) <34 weeks, birth weight <p10 for GA and available results from amniocentesis. All analyses were corrected for potential confounders.

RESULTS

The L/S ratio was significantly higher in the abnormal Doppler group as compared to the normal Doppler group (p=0.02). The L/S ratio was significantly lower in hypertensive pregnancies as compared to normotensive pregnancies (p=0.02). Subdivision of the maternal hypertension group showed a significantly lower L/S ratio in the HELLP syndrome group as compared to the normotension group (p=0.04).

CONCLUSION

The L/S ratio of SGA fetuses is significantly higher in cases with presumed placental insufficiency and significantly lower when pregnancies are complicated by HELLP syndrome. These observations are in line with the hypothesis that placental insufficiency accelerates lung maturation and with recent reports of poorer respiratory outcome in infants from mothers with HELLP syndrome.

Oxidative stress and proinflammatory cytokine levels are increased in premature neonates of preeclamptic mothers with HELLP syndrome

BACKGROUND

Respiratory distress syndrome (RDS) incidence is increased in infants of preeclamptic mothers with hemolysis, elevated liver enzymes, low platelets (HELLP) syndrome. RDS and HELLP syndrome have been associated with oxidative stress and inflammatory processes.

OBJECTIVES

We hypothesize that end-tidal carbon monoxide corrected for inhaled CO (ETCOc), malondialdehyde (MDA) (markers of oxidative stress) and proinflammatory cytokine (IL-6, IL-8) production are higher in infants of preeclamptic mothers with HELLP syndrome than in those of preeclamptic mothers without HELLP syndrome.

METHODS

Prospective study of 36 infants of preeclamptic mothers (GA <32 weeks) admitted to the Neonatal Intensive Care Unit. ETCOc was measured at 0-12, 48-72 and 168 h postnatally using the CO-Stattrade mark End-Tidal Breath Analyzer. Simultaneously, blood was sampled for MDA, IL-8 and IL-6.

RESULTS

At 0-12 h, ETCOc, MDA and IL-8 values (median[range]) were significantly higher in HELLP infants than in infants from preeclamptic mothers without HELLP (ETCOc 2.2 [1.5-3.9] vs. 1.8 [0.5-2.9] ppm; MDA 2.3 [1.3-4.1] vs. 1.5 [0.4-3.1] mumol/l; IL-8 145 [24-606] vs. 62 [26-397] pg/ml; all p <0.05). MDA remained significantly higher during the first 168 h of life (2.3 [0.8-5.8] vs. 1.1 [0.8-3.7] mumol/l, p = 0.02).

CONCLUSION

Oxidative stress and proinflammatory cytokine levels are increased in infants of preeclamptic mothers with HELLP syndrome. These processes may cause inactivation of surfactant explaining the increased RDS incidence in these infants.

Changes in serum adenosine deaminase activity during normal pregnancy

Adenosine deaminase (ADA), an enzyme essential for the differentiation of lymphoid cells, has been used for monitoring diseases with altered immunity. The purpose of this study was to investigate the changes in serum ADA activity throughout normal pregnancy. We measured the catalytic values of serum ADA from 202 normal pregnant women using a commercial kit. Subjects were divided into four groups according to the gestational age in weeks (Gwks) (Group I: 5-9 Gwks [n=58]; Group II: 15-20 Gwks [n= 63]; Group III: 24-30 Gwks [n=34]; Group IV: 30-39 Gwks [n=47]). The serum ADA levels for the Groups I, II, III, and IV were as follows: 20.1 +/- 6.9 IU/L, 20.0 +/- 7.6 IU/L, 37.9 +/- 19.9 IU/L, and 24.5 +/- 8.6 IU/L, respectively. The serum ADA activity of group III was significantly higher than the other groups (p<0.05). However, there was no significant correlation between the Gwks and the serum ADA activity. Furthermore, other parameters, such as maternal age (p=0.29), gestational age at delivery (p=0.07), delivery mode (p=0.39), and birth weight (p=0.59) had no correlation with ADA activity. Reference values of serum ADA in normal pregnancy may provide important database for making clinical decisions in pregnancies complicated by conditions where cellular immunity has been altered.

Oxidative stress and antioxidant defenses in serum of patients with non-alcoholic steatohepatitis

OBJECTIVES

Oxidative stress is an important pathophysiological mechanism in non-alcoholic steatohepatitis (NASH). We aimed to evaluate serum xanthine oxidase (XO) (as a generator of reactive oxygen species), superoxide dismutase (SOD), glutathione peroxidase (GSHPx), paraoxonase (PON1) activities, nitric oxide (NO) and thiol levels in patients with NASH.

DESIGN AND METHODS

A total of 35 patients with NASH and 31 age-and-gender-matched healthy subjects were enrolled in the study as control group. Serum levels of XO, NO, SOD, GSHPx, PON1 and thiol were determined by spectrophotometric methods.

RESULTS

Serum XO activities were higher in the patients with NASH than the controls (p<0.001). Serum NO levels, SOD, GSHPx, PON1 activities and thiol levels were lower in the patients with NASH than the controls (p<0.031, p<0.019, p<0.001, p<0.001, p<0.001, respectively).

CONCLUSIONS

Increased oxidative stress in patients with NASH may result in a pro-oxidation environment, which in turn could result in decreased antioxidant enzyme activities and NO levels. Therefore effective antioxidant therapy to inhibit oxidative stress is necessary and agents to increase antioxidant enzyme may be a therapeutic option in NASH.

Clinical correlation between adenosine deaminase activity and pre-eclampsia severity

This study evaluated the relationship between the activity of the inflammatory indicator adenosine deaminase (ADA) in placental tissue and maternal and fetal (umbilical cord) plasma and the severity of pre-eclampsia. Maternal and umbilical vein whole blood and placental tissue samples were collected from women with normal pregnancies (n = 33) and patients with mild (n = 12) or severe (n = 17) preeclampsia. ADA activity was measured spectrophotometrically. Significantly increased ADA activity was detected in maternal and fetal plasma, and placental tissue in patients with mild and severe pre-eclampsia compared with normal pregnancies; there were no significant differences between the mild and severe cases. The presence of increased ADA activity in pre-eclampsia is consistent with activation of the inflammatory system in this condition. The increased ADA activity was related to the presence of the disease but not the severity of clinical symptoms. Neonatal outcome did not significantly correlate with observed ADA activity.

Increased adenosine deaminase in hydatidiform mole

BACKGROUND

The aim of the current study was to investigate levels of adenosine deaminase in plasma of patients with hydatidiform mole.

METHODS

Plasma adenosine deaminase levels were determined in 17 women with normal pregnant course, in 17 women with hydatidiform mole, and in 17 non-pregnant healthy volunteers.

RESULTS

Mean adenosine deaminase activity in the hydatidiform mole group was 121.5+/-24.8 U/L, significantly higher than in the pregnant control (7.8+/-6.5 U/L; p<0.0001) and non-pregnant control groups (6.4+/-7.4 U/L; p<0.0001). A cutoff level of 40.5 U/L was found, with both sensitivity and specificity of 100%.

CONCLUSIONS

Adenosine deaminase may play a role in the development of hydatidiform mole.