Comparative study of oxidative stress in maternal blood with that of cord blood and maternal milk

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

BACKGROUND

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

METHODS

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

RESULTS

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

DISCUSSION

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

The impact on colostrum oxidative stress, cytokines, and immune cells composition after SARS-CoV-2 infection during pregnancy

Background

Limited data are available regarding the differences between immunological, biochemical, and cellular contents of human colostrum following maternal infection during pregnancy with coronavirus 2 disease (COVID-19).

Objective

To investigate whether maternal COVID-19 infection may affect immunological, biochemical, and cellular contents of human colostrum.

Methods

Using a case-control study design, we collected colostrum from 14 lactating women with a previous diagnosis of COVID-19 during pregnancy and 12 without a clear diagnosis during September 2020 to May 2021. Colostrum samples were analysed for some enzymes and non-enzymatic oxidative stress markers (SOD, CAT, GPx, MDA, GSH, GSSG, H2O2, MPO) and for IL-1β, IL-6, tumour necrosis factor (TNF)-α, protein induced by interferon gamma (IP)-10, IL-8, IFN-λ1, IL12p70, IFN-α2, IFN-λ2/3, granulocyte macrophage colony stimulating factor (GM-CSF), IFN-β, IL-10 and IFN-γ, along with IgA and IgG for the SARS-CoV-2 S protein. We perform immunophenotyping to assess the frequency of different cell types in the colostrum.

Results

Colostrum from the COVID-19 symptomatic group in pregnancy contained reduced levels of H2O2, IFN-α2, and GM-CSF. This group had higher levels of GSH, and both NK cell subtypes CD3-CD56brightCD16-CD27+IFN-γ+ and CD3-CD56dimCD16+CD27- were also increased.

Conclusion

The present results reinforce the protective role of colostrum even in the case of mild SARS-Cov-2 infection, in addition to demonstrating how adaptive the composition of colostrum is after infections. It also supports the recommendation to encourage lactating women to continue breastfeeding after COVID-19 illness.

In-utero exposure to air pollution and early-life neural development and cognition

Air pollution remains one of the major health threats around the world. Compared to adults, foetuses and infants are more vulnerable to the effects of environmental toxins. Maternal exposure to air pollution causes several adverse birth outcomes and may lead to life-long health consequences. Given that a healthy intrauterine environment is a critical factor for supporting normal foetal brain development, there is a need to understand how prenatal exposure to air pollution affects brain health and results in neurological dysfunction. This review summarised the current knowledge on the adverse effects of prenatal air pollution exposure on early life neurodevelopment and subsequent impairment of cognition and behaviour in childhood, as well as the potential of early-onset neurodegeneration. While inflammation, oxidative stress, and endoplasmic reticulum are closely involved in the physiological response, sex differences also occur. In general, males are more susceptible than females to the adverse effect of in-utero air pollution exposure. Considering the evidence provided in this review and the rising concerns of global air pollution, any efforts to reduce pollutant emission or exposure will be protective for the next generation.

Detection of anti-Neospora caninum antibodies in sheep's full-cream milk by a time-resolved fluorescence immunoassay

Ovine neosporosis, caused by the Apicomplexan parasite Neospora caninum, leads to reproductive failure worldwide. Nowadays, there is a trend to develop diagnostic techniques using non-invasive samples, such as milk, in order to reduce animal stress, sample collection effort, and costs. The objective of this study was to develop and validate a highly sensitive and specific serological technique, based on a time resolved-fluorescence immunoassay using a N. caninum GRA7 antigen (GRA7-TRFIA), for the detection of anti-N. caninum immunoglobulins G on sheep' full-cream milk samples. An analytical validation was performed, including intra- and inter-assay precision, analytical sensitivity and accuracy. The diagnostic performance of the assay was evaluated by studying the positive-negative discrimination by Mann Whitney U tests. In additon optimal cut-offs, diagnostic sensitivity and specificity, and areas under the curve were calculated by three Receiver Operating Curve (ROC) analyses, using GRA7-TRFIA and a N. caninum tachyzoite soluble extract-based ELISA (NcSALUVET-ELISA) in blood sera, and the coinciding results of both techniques, as reference techniques. Moreover, Spearman's correlation of GRA7-TRFIA in milk with the techniques in sera and agreement (kappa values) were also estimated. GRA7-TRFIA for milk samples showed an adequate precision, with high analytical sensitivity and accuracy. Regarding ROC analyses, at the optimal cut-offs, the diagnostic sensitivity and specificity were more than 90 % in all cases. In addition, GRA7-TRFIA values in milk were more positively correlated to GRA7-TRFIA values in blood sera than in the case of values obtained with NcSALUVET-ELISA. GRA7-TRFIA in milk showed an almost perfect agreement with GRA7-TRFIA in blood sera (kappa = 0.98) and with the coinciding results of GRA7-TRFIA and NcSALUVET in blood sera (kappa = 1.00), while it has a substantial agreement with NcSALUVET-ELISA (kappa = 0.69). In the light of these results, GRA7-TRFIA in full-cream milk samples is a highly sensitive technique that could be used for screening anti-N. caninum antibodies in sheep flocks.

Interactions between preeclampsia and composition of the human milk: what do we know?

Purpose: Preeclampsia (PE) is a gestational hypertensive syndrome characterized by a complex disease with variable clinical manifestation. An aspect of increased interest is the possible effect of PE on the mammary gland (and therefore on breast milk composition) considering that a mother's own milk is always considered the first choice for the nutrition of all neonates. Human milk (HM) is a unique food believed to contain biological factors involved in both short and long-term benefits. This article aims to review the published papers on this topic and to offer additional insights on the role of this gestational pathology on the composition of HM.Materials and methods: This review was performed by searching the MEDLINE, EMBASE, CINHAL, and Cochrane Library databases.Results: A total of 15 articles were selected.Conclusions: Overall, the findings from the literature suggest that PE can alter the composition of HM milk. Nevertheless, the number of studies in this field are scarce, and the related protocols present some limitation, for example, evaluating the variability of just a few specific milk biochemical markers in association with this syndrome.

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.

Increasing selenium supply for heat-stressed or actively cooled sows improves piglet preweaning survival, colostrum and milk composition, as well as maternal selenium, antioxidant status and immunoglobulin transfer

This study aimed to evaluate the effects of increasing selenium (Se) supply for heat-stressed or actively cooled sows on sow productivity, colostrum and milk composition, as well as the selenium and antioxidant status and immunoglobulin levels of sows and nursing piglets. The study was a 2 × 2 factorial design, where the first factor was farrowing environment [heat stress vs. actively cooling, temperature: 29.61 ± 0.19 ℃ (27.70-31.60 ℃) vs. 27.90 ± 0.15 ℃ (26.90-30.20 ℃); temperature-humidity index: 72.91 ± 0.26 (70.30-75.70) vs. 70.81 ± 0.22 (69.30-73.80)], and the second factor was dietary Se level during late gestation and lactation [(0.3 vs. 1.2 mg/kg Se as Se-yeast, the basal diet was corn-soybean meal diet formulated according to NRC (2012) except for Se level]. Forty multiparous sows (Landrace × Yorkshire) were randomly allotted to 1 of 4 treatments (10 sows and following 90 piglets per treatment, respectively). The results show that: (1) There were no interactions of farrowing environment with Se treatments with the exceptions of nutrient content of 7-d milk; (2) As for zootechnical measures, piglets of sows receiving increasing Se tended to have greater preweaning survival compared with those of sows receiving control diet without interactions of environment and Se treatments; (3) As to colostrum and milk composition, greater concentrations of protein, lactose, solids-not-fat in colostrum, and greater fat concentration in 7-d and 14-d milk were found for sows fed increasing Se; (4) Regarding Se and antioxidant status, increasing Se supply for sows increased Se content in colostrum and 21-d milk, as well as in plasma of 1-day-old and 21-day-old piglets. Meanwhile, increasing Se supply for sows improved antioxidant status in colostrum (MDA content) and 21-d milk (T-AOC and MDA content), as well as in plasma of 1-day-old and 21-day-old piglets (GSH-Px activity and MDA content); (5) With regard to immunoglobulins, sows fed increasing Se had higher IgM levels in colostrum, and higher IgA in 21-d milk. Also, piglets from sows fed increasing Se had higher plasma IgA at 1 d of age, and higher IgA and IgG levels at 21 d of age. Collectively, increasing selenium supply for heat-stressed or actively cooled sows improved piglet preweaning survival, colostrum and milk composition, as well as maternal selenium, antioxidant status and immunoglobulin transfer irrespective of the climatic conditions, which indicates that Se requirements for sows should be urgently reassessed.

Association between maternal vitamin E status and alpha-tocopherol levels in the newborn and colostrum

Vitamin E is important because of its antioxidant activity in situations of oxidative stress, especially postnatally. Hence, the objective was to verify whether maternal alpha-tocopherol level is associated with the alpha-tocopherol levels of the newborn and colostrum. This is a cross-sectional study of 58 women and their term newborns from a public hospital. Blood and colostrum were collected to measure alpha-tocopherol levels by high-performance liquid chromatography. Mothers with serum alpha-tocopherol levels <16.2 mmol L(-1) and newborns <11.6 mmol L(-1) were indicative of deficiency or low levels. Mothers were divided into two groups: <16.2 mmol L(-1) and those with levels ≥16.2 mmol L(-1) . The mean (95% confidence interval) serum alpha-tocopherol levels of mothers, umbilical cords and colostrum were 28 (24-32), 6 (5-8) and 39 mmol L(-1) (32-45), respectively (P < 0.001); 19% of the women and 90% of the newborns had low alpha-tocopherol levels. Maternal alpha-tocopherol level was associated with that of the umbilical cord. Newborns from mothers at risk of deficiency had low alpha-tocopherol levels (P < 0.001). Colostrum levels of vitamin E were not influenced by maternal serum. Maternal deficiency influenced the vitamin E level of the umbilical cord but does not in the colostrum, evidencing distinct transfer mechanisms via the mammary gland.

Preeclampsia As Modulator of Offspring Health

A balanced intrauterine homeostasis during pregnancy is crucial for optimal growth and development of the fetus. The intrauterine environment is extremely vulnerable to multisystem pregnancy disorders such as preeclampsia, which can be triggered by various pathophysiological factors, such as angiogenic imbalance, immune responses, and inflammation. The fetus adapts to these conditions by a mechanism known as developmental programming that can lead to increased risk of chronic noncommunicable diseases in later life. This is shown in a substantial number of epidemiological studies that associate preeclampsia with increased onset of cardiovascular and metabolic diseases in the later life of the offspring. Furthermore, animal models based predominantly on one of the pathophysiological mechanism of preeclampsia, for example, angiogenic imbalance, immune response, or inflammation, do address the susceptibility of the preeclamptic offspring to increased maternal blood pressure and disrupted metabolic homeostasis. Accordingly, we extensively reviewed the latest research on the role of preeclampsia on the offspring's metabolism and cardiovascular phenotype. We conclude that future research on the pathophysiological changes during preeclampsia and methods to intervene in the harsh intrauterine environment will be essential for effective therapies.

Influence of prematurity and birth weight on the concentration of α-tocopherol in colostrum milk

OBJECTIVE:

To assess vitamin E levels in the breast milk, analyzing the prematurity and the birth weight influence in α-tocopherol concentration of colostrum milk.

METHODS:

Cross-sectional study, in which the colostrum was collected from 93 nursing mothers in a public maternity of Natal, Rio Grande do Norte, Northeast Brazil. The newborns were classified based on gestational age and birth weight. The analysis of α-tocopherol in the milk was carried out by high performance liquid chromatography.

RESULTS:

The α-tocopherol concentration in the colostrum of lactating women whose children were born at term was 1,093.6±532.4µg/dL; for preterm infants, the concentration was 1,321.6±708.5µg/dL (p=0.109). In the preterm group, the α-tocopherol concentration in the colostrum of lactating women whose children were born with low and normal birth weight was 1,316.0±790.7 and 1,327.2±655.0µg/dL, respectively (p=0.971). In the term group, the α-tocopherol levels were higher in mothers of children with birth weight >4000g, being 1,821.0±575.4µg/dL, compared to 869.5±532.1µg/dL and 1,039.6±477.5µg/dL with low and adequate birth weight, respectively (p>0.05).

CONCLUSIONS:

Prematurity did not influence α-tocopherol levels in the colostrum milk. Mothers who had macrossomic term neonates presented increased α-tocopherol levels. These results indicate that birth weight can influence α-tocopherol leves in the colostrum milk.

Diet supplementation during early lactation with non-alcoholic beer increases the antioxidant properties of breastmilk and decreases the oxidative damage in breastfeeding mothers

BACKGROUND

After delivery and birth, mothers and neonates are exposed to oxidative stress. We tested whether supplementing the diet of breastfeeding mothers with non-alcoholic beer, a product rich in antioxidants, could improve their oxidative status and the antioxidant content of their milk. A prospective trial begun on Day 2 postpartum was conducted in mother-infant dyads.

SUBJECTS AND METHODS

Sixty breastfeeding mothers and their infants were allocated to either a control group (n=30) on a free diet or a study group (n=30) on a free diet supplemented with 660 mL of non-alcoholic beer/day. The oxidative status of the mothers' breastmilk, plasma, and urine and the infant's urine was analyzed on Days 2 and 30 postpartum. The before-after difference was compared within and between the groups.

RESULTS

The increase in antioxidant capacity and coenzyme Q10 content in the breastmilk of the study group at Day 30 was higher than in that of the control group (p<0.001). There was also a change in the oxidative status of the mothers' plasma in the supplemented group regarding the control group; higher values of total antioxidant capacity (p<0.05) and lower levels of 8-hydroxydeoxyguanosine (p<0.05), indicative of DNA oxidative damage, were found. These results indicate a positive effect of non-alcoholic beer supplementation on oxidative stress in mothers. However, no difference in oxidant markers was found in the infant's urine.

CONCLUSIONS

The consumption of non-alcoholic beer appears to enhance the antioxidant capacity of breastmilk and decrease oxidative damage in breastfeeding mothers.

Polycyclic aromatic hydrocarbons (PAHs) as determinants of various anthropometric measures of birth outcome

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental contaminants that are known to induce oxidative stress. There have been several reports about the link between PAH exposure and complications in pregnancy. This cross-sectional study was conducted to: (1) measure the levels of benzo(a)anthracene (BaA), chrysene (Ch), benzo(b)fluoranthene (BbF), benzo(a)pyrene (BaP), and dibenzo(a,h)anthracene (DBahA) in placentas and maternal and -umbilical cord blood obtained at delivery from 1578 women between June 2005 and 2006 in the area of Al-Kharj, Saudi Arabia; (2) assess their influence on various anthropometric measures of birth outcome taking into consideration the carcinogenic properties of these PAHs; and (3) determine the degree of PAH-related oxidative DNA damage and birth outcome. Among the five tested PAHs, only BaP was carcinogenic; therefore, the levels of the other four probable or possible carcinogenic PAHs (BaA, Ch, BaF, and DBahA) were summed as ∑4-PAHs. Levels of 1-hydroxypyrene (1-HP) were determined in maternal urine samples as a biomarker of PAH internal dose. Urinary cotinine (COT) was measured as an index of smoking. The following markers of oxidative stress were selected: malondialdehyde (MDA) in cord (C-MDA) and maternal (M-MDA) serum and 8-hydroxy-2-deoxyguanosine (8-OHdG) in maternal urine. None of the tested PAHs was found in maternal or cord blood. However, all five PAH compounds were detected in placentas; Ch was the highest (6.582 μg/kg dry wt.), and BaA was the lowest (0.236 μg/kg dry wt.). The mean concentration of urinary 1-HP found in this study was 0.216 ± 0.856 μg/g Cr. After adjusting for gestational age and other confounding variables, regression models revealed an inverse relationship between placental weight, cord length and placental BaP. A similar trend was observed between cord length and ∑4-PAHs in placental tissues. Urinary 1-HP, though, cannot be used as an unequivocal biomarker of PAH exposure, but it can be an appropriate indicator of exposure to environmental tobacco smoke (ETS). The data demonstrate that ETS exposure (as measured by urinary COT) may adversely affect birth outcome as shown by reduced head circumference, birth weight, and birth length, as well as increased cephalization index. The positive relationship between 8-OHdG levels and 1-HP in urine provides evidence of an oxidative stress mechanism. Although this study provides no direct evidence of an association between PAH exposure and DNA damage, increased oxidative stress in the form of lipid peroxidation significantly affected various birth measures. Therefore, there is a need for studies regarding PAH exposure and its associated biological effects to determine the extent of potential fetal damage as well as possible long-term effects, such as cancer.

Pre-eclampsia and offspring cardiovascular health: mechanistic insights from experimental studies

Pre-eclampsia is increasingly recognized as more than an isolated disease of pregnancy. Women who have had a pregnancy complicated by pre-eclampsia have a 4-fold increased risk of later cardiovascular disease. Intriguingly, the offspring of affected pregnancies also have an increased risk of higher blood pressure and almost double the risk of stroke in later life. Experimental approaches to identify the key features of pre-eclampsia responsible for this programming of offspring cardiovascular health, or the key biological pathways modified in the offspring, have the potential to highlight novel targets for early primary prevention strategies. As pre-eclampsia occurs in 2–5% of all pregnancies, the findings are relevant to the current healthcare of up to 3 million people in the U.K. and 15 million people in the U.S.A. In the present paper, we review the current literature that concerns potential mechanisms for adverse cardiovascular programming in offspring exposed to pre-eclampsia, considering two major areas of investigation: first, experimental models that mimic features of the in utero environment characteristic of pre-eclampsia, and secondly, how, in humans, offspring cardiovascular phenotype is altered after exposure to pre-eclampsia. We compare and contrast the findings from these two bodies of work to develop insights into the likely key pathways of relevance. The present review and analysis highlights the pivotal role of long-term changes in vascular function and identifies areas of growing interest, specifically, response to hypoxia, immune modification, epigenetics and the anti-angiogenic in utero milieu.