Colostrum of Preeclamptic Women Has a High Level of Polyphenols and Better Resistance to Oxidative Stress in Comparison to That of Healthy Women

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.

Effect of peroxiredoxin 1 on the regulation of trophoblast function by affecting autophagy and oxidative stress in preeclampsia

PURPOSE

PE is a pregnancy-specific syndrome and one of the main causes of maternal, fetal, and neonatal mortality. PRDX1 is an antioxidant that regulates cell proliferation, differentiation, and apoptosis. The aim of this study is to investigate the effect of PRDX1 on the regulation of trophoblast function by affecting autophagy and oxidative stress in preeclampsia.

METHODS

Western blotting, RT-qPCR, and immunofluorescence were used to examine the expression of PRDX1 in placentas. PRDX1-siRNA was transfected to knockdown PRDX1 in HTR-8/SVneo cells. The biological function of HTR-8/SVneo cells was detected by wound healing, invasion, tube formation, CCK-8, EdU, flow cytometry, and TUNEL assays. Western blotting was used to detect the protein expression of cleaved-Caspase3, Bax, LC3II, Beclin1, PTEN, and p-AKT. DCFH-DA staining was used to detect ROS levels by flow cytometry.

RESULTS

PRDX1 was significantly decreased in placental trophoblasts in PE patients. Following the exposure of HTR-8/SVneo cells to H₂O₂, PRDX1 expression was significantly decreased, LC3II and Beclin1 expression was notably increased, and ROS level was also markedly increased. PRDX1 knockdown impaired migration, invasion, and tube-formation abilities and promoted apoptosis, which was accompanied by an increased expression of cleaved-Caspase3 and Bax. PRDX1 knockdown induced a significant decrease in LC3II and Beclin1 expression, along with an elevated p-AKT expression and a decreased PTEN expression. PRDX1 knockdown increased intracellular ROS levels, and NAC attenuated PRDX1 knockdown-induced apoptosis.

CONCLUSION

PRDX1 regulated trophoblast function through the PTEN/AKT signaling pathway to affect cell autophagy and ROS level, which provided a potential target for the treatment of PE.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

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.

Phytochemicals in breast milk and their benefits for infants

Exclusive breastfeeding is widely recommended at least during the first 6 months of life and breast milk (BM) composition depends on maternal diet. Phytochemicals, including polyphenols and carotenoids, are recognized by their powerful antioxidant activities being present in BM. This review provides an overview of BM composition with respect to polyphenols and carotenoids evaluating its possible benefits for the infant. Polyphenols do not have any body deposit and their content in BM depends on regular dietary intake from mothers and bioavailability of them, while carotenoids content in BM changed depending on factors including stages of breastfeeding, maternal diet and maternal health status. Preeclampsia, overweight or obesity are conditions able to reduce polyphenols and carotenoids in BM by using them as antioxidants. For both polyphenols and carotenoids, the supplementation slightly enhances their BM content. Few studies have shown the presence of phytochemicals in infant plasma and still remains unclear the benefits that polyphenols and carotenoids provide for development of infants. Further studies using long-term, randomized and controlled designs are necessary to determine the relation between carotenoids, polyphenols and its potential benefits for early childhood.

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

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

Gestational Weight Gain Influences the Adipokine-Oxidative Stress Association during Pregnancy

INTRODUCTION AND OBJECTIVE

The weight gained during pregnancy could determine the immediate and future health of the mother-child dyad. Excessive gestational weight gain (EGWG) due to abnormal adipose tissue (AT) accumulation is strongly associated with adverse perinatal outcomes as gestational diabetes, macrosomia, obesity, and hypertension further in life. Dysregulation of adipokine, AT dysfunction, and an imbalance in the prooxidant-antioxidant systems are critical features in altered AT accumulation. This study was aimed to investigate the association between adipokines and oxidative stress markers in pregnant women and the influence of the GWG on this association.

METHODS

Maternal blood samples were obtained in the third trimester of pregnancy (n = 74) and serum adipokines (adiponectin, leptin, and resistin), oxidative damage markers: 8-oxo-2'-deoxyguanosine (8-oxodG), lipohydroperoxides (LOOH), malondialdehyde (MDA), and carbonylated proteins (CP), and glucose a metabolic marker were measured.

RESULTS

Women with EGWG had low adiponectin levels than women with adequate weight gain (AWG) or insufficient weight gain (IWG). Multiple linear regression models revealed a positive association between adiponectin and 8-oxodG in women with AWG (B = 1.09, 95% CI: 164-222, p = 0.027) and IWG (B = 0.860, 95% CI: 0.199-1.52, p = 0.013) but not in women with EGWG. In women with EGWG, leptin was positively associated with LOOH (p = 0.018), MDA (p = 0.005), and CP (p = 0.010) oxidative markers.

CONCLUSION

Our findings suggest that concurrent mechanisms regulate adipokine production and oxidative stress in pregnant women and that this regulation is influenced by GWG, probably due to an excessive AT accumulation.

Canine colostrum exosomes: characterization and influence on the canine mesenchymal stem cell secretory profile and fibroblast anti-oxidative capacity

Background

Canine colostrum milk (CCM) is a specific secretion of the mammary gland that is fundamental for the survival of the newborn. CCM has many described components (immunoglobulins, proteins or fat), but its small vesicles, named exosomes, are largely unknown.

Results

A characterization of CCM exosomes was performed. Exosomes were abundant in CCM and appeared with the characteristic cup-shaped morphology and well-defined round vesicles. The size distribution of exosomes was between 37 and 140 nm, and western blot analysis showed positive expression of specific exosomal markers. Proteomic analysis revealed a total of 826 proteins in exosome cargo. We also found that exosomes modified the proliferation and secretory profiles in canine mesenchymal stem cells derived from bone marrow (cBM-MSCs) and adipose tissue (cAd-MSCs). Additionally, CCM exosomes demonstrated a potent antioxidant effect on canine fibroblasts in culture.

Conclusions

Our findings highlight, for the first time, the abundant presence of exosomes in CCM and their ability to interact with mesenchymal stem cells (MSCs). The addition of exosomes to two types of MSCs in culture resulted in specific secretory profiles with functions related to angiogenesis, migration and chemotaxis of immune cells. In particular, the cAd-MSCs secretory profile showed higher potential in adipose tissue development and neurogenesis, while cBM-MSC production was associated with immunity, cell mobilization and haematopoiesis. Finally, exosomes also presented antioxidant capacity on fibroblasts against reactive oxygen species activity within the cell, demonstrating their fundamental role in the development and maturation of dogs in the early stages of their life.

Supplementary information

Supplementary information accompanies this paper at 10.1186/s12917-020-02623-w.

Biomarkers of placental redox imbalance in pregnancies with preeclampsia and consequent perinatal outcomes

OBJECTIVE

To compare redox and inflammatory markers between normal and PE-derived placentas and to evaluate the relationship between placental redox imbalance markers and perinatal outcomes in pregnancies with PE.

METHODS

This was a cross-sectional study conducted at the maternity hospital of a university hospital in Maceio-Alagoas, Brazil, in 2017, including women diagnosed with PE and healthy pregnant women and their conceptuses. After screening, standardized questionnaires containing socioeconomic, clinical, obstetric and anthropometric data were applied. After delivery, placental samples were collected for quantification of biomarkers of redox imbalance (catalase - CAT; malondialdehyde - MDA; hydrogen peroxide - H₂O₂; superoxide dismutase - SOD; reduced glutathione - GSH; oxidized glutathione - GSSG; and their ratio - GSH/GSSG) and inflammation (myeloperoxidase - MPO; interleukin (IL)-6; IL-8; IL-10; and tumor necrosis factor-alpha - TNF-α). All biomarkers were evaluated via linear regression with adjustments of variables with measures of weight, length, head circumference (HC), chest circumference (CC) and gestational age of newborns at birth, considering p < 0.05 as significant.

RESULTS

A total of 100 pregnant women with PE and 50 healthy pregnant women were studied. Higher placental levels of catalase (p = 0.018), SOD (p = 0.031), the GSH/GSSG ratio (p = 0.019) and IL-6 (p = 0.010) and lower GSSG (p = 0.001) were observed in pregnant women with PE than in the control group. Positive associations between placental GSH levels and body weight, HC, CC and gestational age at birth (p < 0.05) were identified.

CONCLUSION

PE-derived placentas had high concentrations of some antioxidants (enzymes and thiols), which might be a compensation mechanism against oxidative stress. Placental GSH levels were the only biomarker, among the studied ones, related positively with beneficial perinatal outcomes, suggesting that this endogenous antioxidant plays an important role in maintaining the health of the conceptus and women with PE.

Effect on Adipose Tissue of Diabetic Mice Supplemented with n-3 Fatty Acids Extracted from Microalgae

BACKGROUND

Type 2 Diabetes Mellitus (T2DM) is considered a chronic noncommunicable disease in which oxidative stress is expected as a result of hyperglycaemia. One of the most recent approaches is the study of microalgae fatty acids and their possible antioxidant effect.

OBJECTIVE

This study aimed to analyse the effect of supplementation with n-3 fatty acids extracted from microalgae on the total antioxidant capacity (TAC) and lipid peroxidation of adipose tissue and plasma from diabetic (db/db) and healthy (CD1) mice.

METHODS

Mice were supplemented with lyophilized n-3 fatty acids extracted from microalgae or added to the diet, from week 8 to 16. TAC assay and Thiobarbituric Acid Reactive Substances assay (TBARS) were performed on adipose tissue and plasma samples.

RESULTS

The supplementation of lyophilized n-3 fatty acids from microalgae increased the total antioxidant capacity in adipose tissue of diabetic mice (615.67μM Trolox equivalents vs 405.02μM Trolox equivalents from control mice, p<0.01) and in the plasma of healthy mice (1132.97±85.75μM Trolox equivalents vs 930.64±32μM Trolox equivalents from modified diet mice, p<0.01). There was no significant effect on lipid peroxidation on both strains.

CONCLUSION

The use of n-3 fatty acids extracted from microalgae could be a useful strategy to improve total antioxidant capacity in T2DM.