The Nutrition in Early Life and Asthma (NELA) birth cohort study: Rationale, design, and methods

Breastmilk polyamines modify gut gene expression in children at three months of age

BACKGROUND & AIMS

Breastmilk is one of the main sources of exogenous polyamines for newborns and contains higher polyamine content than infant formulas. Polyamines are involved in gut maturation and immune system regulation in animals, although the underlying mechanisms are not fully understood. We quantified polyamines in human mature breastmilk and evaluate their effects on intestinal gene expression in babies at three months of age.

METHODS

Polyamines were quantified in mature milk of 195 women from the prospective Mediterranean NELA birth cohort (Murcia, Spain) at 3 months postpartum. Maternal dietary intake was assessed by food frequency questionnaires. Intestinal gene expression was analysed in babies receiving breastmilk, with high (>p50, n = 25) or low (

RESULTS

Spermidine and spermine were the most prevalent polyamines in breastmilk at 3 months postpartum, while levels of putrescine were lower. Maternal dietary intake of polyamines was not associated with polyamine concentration in breastmilk and there were no differences in the polyamine content between allergic and non-allergic mothers. Microarray analyses of exfoliated gut cells revealed that cell localization and immune system were the most significant biological processes affected by high vs low polyamines in breastmilk. There were 15 differentially expressed genes, 3 up-regulated and 12 down-regulated, in high compared to low polyamine groups. Among the up-regulated genes were tumour necrosis factor alpha-induced protein 6 (TNFAIP6) and interleukin 8; while other immune system-related genes, such as integral membrane protein 2C, lymphocyte antigen 6 complex, transmembrane protein 179B were down-regulated.

CONCLUSIONS

Mature breastmilk presents spermidine and spermine as the most prevalent polyamines. Babies receiving milk with higher polyamine levels showed differences in the expression of genes associated with cell localization and immune system processes.

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Key Words

• Breastmilk
• Exfoliome
• Gene expression
• Intestine
• Polyamines
• Transcriptome

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MESH Headings

• Humans
• Female
• Polyamines/analysis
• Infant
• Milk, Human/chemistry
• Prospective Studies
• Spermidine/analysis
• Adult
• Spain
• Spermine/analysis
• Putrescine/analysis
• Male
• Gene Expression

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Affiliation(s)

María Sánchez-Campillo Biomedical Research Institute of Murcia (IMIB-Arrixaca), Murcia, Spain; Department of Physiology, University of Murcia, Murcia, Spain
Antonio Gázquez Biomedical Research Institute of Murcia (IMIB-Arrixaca), Murcia, Spain; Department of Physiology, University of Murcia, Murcia, Spain; Maternal and Child Health and Development Research Network (RICORS-SAMID), Institute of Health Carlos III, Madrid, Spain
María T Pastor-Fajardo Biomedical Research Institute of Murcia (IMIB-Arrixaca), Murcia, Spain; Department of Pediatrics, Hospital General Universitario de Elche, Alicante, Spain
María J López-Andreo Biology Molecular Section (ACTI), University of Murcia, Murcia, Spain
Adrián Pérez-Andrés Department of Physiology, University of Murcia, Murcia, Spain
Carmen Martínez-Graciá Biomedical Research Institute of Murcia (IMIB-Arrixaca), Murcia, Spain; Food Science and Technology Department, Faculty of Veterinary, University of Murcia, Murcia, Spain
Jesús Vioque Health and Biomedical Research Institute of Alicante, University Miguel Hernandez (ISABIAL-UMH), Alicante, Spain; CIBER Epidemiology and Public Health (CIBERESP), Madrid, Spain
Virginia Pérez-Fernández Biomedical Research Institute of Murcia (IMIB-Arrixaca), Murcia, Spain; Department of Sociosanitary Sciences, Faculty of Medicine, University of Murcia, Murcia, Spain
Luís García-Marcos Biomedical Research Institute of Murcia (IMIB-Arrixaca), Murcia, Spain; Network of Asthma and Adverse and Allergic Reactions (ARADyAL), Madrid, Spain; Pediatric Allergy and Pulmonology Units, Virgen de la Arrixaca University Children's Hospital, University of Murcia, Murcia, Spain
Elvira Larqué Biomedical Research Institute of Murcia (IMIB-Arrixaca), Murcia, Spain; Department of Physiology, University of Murcia, Murcia, Spain; Maternal and Child Health and Development Research Network (RICORS-SAMID), Institute of Health Carlos III, Madrid, Spain.

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Impact of environmental exposures on exhaled breath and lung function: NELA Birth Cohort

Introduction

Exposure to environmental factors (i.e. air pollution and second-hand tobacco smoke) have been associated with impaired lung function. However, the impact of environmental factors on lung health is usually evaluated separately and not with an exposomic framework. In this regard, breath analysis could be a noninvasive tool for biomonitoring of global human environmental exposure.

Methods

Data come from 337 mother-child pairs from the Nutrition in Early Childhood Asthma (NELA) birth cohort. Levels of BTEX (benzene, toluene, ethylbenzene and xylenes) in exhaled breath from mothers and children at 3 months after birth were estimated using gas chromatography-mass spectrometry. Short-term residential exposures (breath sampling day and 15 days before breath sampling) to nitrogen dioxide, particulate matter (PM2.5) and ozone were determined by chemical dispersion/transport modelling. Forced vital capacity, forced expiratory volume in 0.5 s (FEV0.5) and forced expiratory flow at 75% of FVC and at 25%-75% of FVC were measured in infants according to the raised-volume rapid thoracoabdominal compression technique.

Results

The results showed significant associations between short-term exposure to external agents and levels of benzene and toluene in exhaled breath. It was observed that exhaled levels of benzene and toluene were influenced by smoking status and outdoor air pollution in mothers, and by air pollution in infants (3 months of age). No significant relationship was observed between exposure to maternal tobacco smoking and/or short-term air pollution and lung function in healthy infants. However, there was a significant relationship between FEV0.5 and exhaled toluene in children.

Discussion

These findings indicated a significant relationship between environmental exposures and exhaled levels of benzene and toluene, suggesting that breath analysis could be a helpful exposure biomonitoring tool.

Validity of a Short Food Frequency Questionnaire for Toddlers of NELA Birth Cohort Study

BACKGROUND/OBJECTIVES

Our aim was to evaluate the reproducibility and validity of a semi-quantitative food frequency questionnaire (FFQ) for the assessment of usual nutrient and food intakes in children of 18 months old.

METHODS

We included 103 toddlers aged 18 months from the Nutrition in Early Life and Asthma (NELA) birth cohort study. A 47-item FFQ was administered twice to parents with a 3-month interval. During that period, we also performed three non-consecutive 24 h dietary recalls (24hDRs) and oral mucosa samples for determining the fatty acid profile (glycerophospholipids). We estimated correlation coefficients of reproducibility for nutrient and food group intakes by comparing both FFQs and validity coefficients by comparing nutrient intakes between the second FFQ and the average of the three 24hDRs. We also explored biochemical validity by comparing the intake of fish from the FFQ with the percentage of fatty acids in oral mucosa cells.

RESULTS

The average of correlation coefficients for FFQ reproducibility was r = 0.48 for energy-adjusted nutrient intakes (ranging from r = 0.28 for Na to r = 0.62 for Mg and Zn) and r = 0.35 for the intake of energy-adjusted food groups. The average correlation coefficient for FFQ validity on nutrient intakes was r = 0.48, ranging from r = 0.16 for α-carotene to r = 0.75 for vitamin E. We also found a positive correlation between total omega-3 fatty acids and docosahexaenoic acid percentages in oral mucosa cells and the intake of total and white fish, r = 0.31 and r = 0.34, respectively.

CONCLUSIONS

This study shows that our short FFQ demonstrated moderate reproducibility (mean r = 0.48) and validity (mean r = 0.48) for dietary assessment of most nutrients and foods in 18-month-old children in Spain. This FFQ provides an efficient and minimally invasive method for evaluating toddler dietary intake, particularly in Mediterranean contexts.

Urinary concentrations of non-essential and essential elements during weaning in infants from the NELA cohort in Spain

Infancy is a period of continuous growth and development, where inadequate intake of essential elements and exposure to non-essential elements may have lifelong health consequences. Thus, the aim of this study is to evaluate the urine concentration of essential and non-essential elements as a proxy for internal exposure during the weaning period, from 3 to 18 months of age. The Nutrition in Early Life and Asthma (NELA) birth cohort generated the data for this study. Sociodemographic, dietary, and urine concentration of essential (Co, Cu, Mo, I, Fe, Mn, Se, Zn, and Ni) and non-essential elements (Al, V, As, Cd, Sb, Tl, and Pb) data were available for 490 participants at 3 months of age and 216 participants at 18 months of age. Paired urine samples at both time periods were available for 175 infants. At 3 months of age, exclusively breastfed infants had lower urine concentrations of Al, V, Fe, Co, Se, Sb, and Tl. Notably, the concentration of Mo had a median (IQR) of 0.60 (0.40-2.10) μg/L compared to a median (IQR) of 39.80 (25.00-56.40) μg/L observed in infants exclusively fed with formula. When we analyzed the change in urine elements concentrations between 3 and 18 months of age, we observed increased As (0.75 vs. 18.60 μg/L), Co (0.05 vs. 0.24 μg/L), Mo (1.98 vs. 50.0 μg/L), Pb (0.15 vs. 0.69 μg/L), Se (11.3 vs. 23.1 μg/L), Tl (0.02 vs. 0.11 μg/L), and V (0.05 vs. 0.11 μg/L). For Cu, lower urine concentrations were observed at 18 months of age in comparison with concentrations at 3 months (5.77 vs. 4.41 μg/L). Among the main food items identified as driving the changes in urine concentration between 3 and 18 months of age were white fish, rice and pasta, potato chips, custard, small blue fish, and legumes. Exclusively breastfed infants showed lower exposure to non-essential elements compared to those who were fed with a mixture or formula. With the introduction of solid foods, the exposure to some non-essential elements increased drastically, as in the case of As and Pb. In addition, exposure to the essential metal Mo also increased substantially with the introduction of solid food.

Role of body mass index in unbalanced (dysanaptic) lung growth of healthy infants

RATIONALE

Imbalance between forced expiratory volume in the first second (FEV1) and forced vital capacity (FVC) (dysanapsis) has been reported in children who are obese. This dysanaptic growth might begin at an early age, although there are no data on children younger than 6 years.

OBJETIVES

To assess whether body mass index (BMI) and early weight gain, in healthy infants born at term, plays a significant role in the imbalance between FEV1 and FVC, even in the absence of obesity.

METHODS

Lung function was measured by means of raised volume rapid thoracic compression in 69 healthy infants born at term from the Nutrition in Early Life and Asthma cohort. Dysanapsis was defined as zFVC >0.674, zFEV0 .5 ≥-1.645, and FEV0 .5/FVC ≤-1.645. Weight gain (g/day) and growth rate (cm/year) were calculated as the difference between weight and length on the test date and those at birth. To assess the relationship between zBMI and dysanapsis, a receiver operating characteristic curve was performed. Multivariable analysis was carried out by means of linear regressions (one for each lung function index) and by logistic regression for dysanapsis (yes/no).

RESULTS

Higher zBMI was associated with risk of dysanapsis (odds ratio: 3.53, [95% confidence interval: 1.30; 9.66]; p = .014): Each additional zBMI unit was associated with ~10 mL higher FVC and with ~3.5% lower FEV0.5/FVC. Weight gain was associated with lower FEV0.5/FVC ratio.

CONCLUSION

Dysanaptic development of lung function begins very early in infancy and is related with weight gain and body mass index, even in the absence of obesity.

Plasma polyamines during pregnancy and their relationships with maternal allergies and the immune response of the neonates

BACKGROUND

Some studies have reported that polyamine levels may influence immune system programming. The aim of this study was to evaluate the polyamine profile during gestation and its associations with maternal allergy and cytokine production in cord blood cells in response to different allergenic stimuli.

METHODS

Polyamines were determined in plasma of pregnant women (24 weeks, N = 674) and in umbilical cord samples (N = 353 vein and N = 160 artery) from the Mediterranean NELA birth cohort. Immune cell populations were quantified, and the production of cytokines in response to different allergic and mitogenic stimuli was assessed in cord blood.

RESULTS

Spermidine and spermine were the most prevalent polyamines in maternal, cord venous, and cord arterial plasma. Maternal allergies, especially allergic conjunctivitis, were associated with lower spermine in umbilical cord vein. Higher levels of polyamines were associated with higher lymphocyte number but lower Th2-related cells in cord venous blood. Those subjects with higher levels of circulating polyamines in cord showed lower production of inflammatory cytokines, especially IFN-α, and lower production of Th2-related cytokines, mainly IL-4 and IL-5. The effects of polyamines on Th1-related cytokines production were uncertain.

CONCLUSIONS

Spermidine and spermine are the predominant polyamines in plasma of pregnant women at mid-pregnancy and also in umbilical cord. Maternal allergic diseases like allergic conjunctivitis are related to lower levels of polyamines in cord vein, which could influence the immune response of the newborn. Cord polyamine content is related to a decreased Th2 response and inflammatory cytokines production, which might be important to reduce an allergenic phenotype in the neonate.

Maternal non-compliance with recommended folic acid supplement use alters global DNA methylation in cord blood of newborns: A cohort study

BACKGROUND & AIMS

Prenatal folate exposure may alter epigenetic marks in the offspring. We aimed to evaluate associations between prenatal exposure to folic acid (FA) in preconception and in utero with cord blood DNA methylation in long interspersed nuclear element 1 (LINE-1) and Alu short interspersed nuclear elements (SINEs) as markers of global DNA methylation levels.

METHODS

Data come from 325 mother-child pairs participating in the Nutrition in Early Life and Asthma (NELA) birth cohort (2015-2018). Pregnant women were asked about supplement use, including brand name and dose, one month before pregnancy (preconception) and through the trimesters of pregnancy. Maternal dietary folate intake was assessed using a validated food frequency questionnaire with additional questions for FA supplement use. Folate serum levels were measured in mothers at 24 weeks of gestation and in cord blood of newborns. DNA methylation was quantitatively assessed by bisulfite pyrosequencing on 5 LINE-1 and 3 Alu different elements. Associations were estimated using multivariable linear regression models.

RESULTS

A reduction in methylation levels of LINE-1 in newborns was associated with the use of FA supplements below the recommended doses (<400 ug/day) during preconception (-0.50; 95% CI: -0.91, -0.09; P = 0.016), and from preconception up to 12 weeks of gestation (-0.48; 95% CI: -0.88, -0.08; P = 0.018). Maternal use of FA supplements above the tolerable upper intake level of 1000 ug/day from preconception until 12 weeks of gestation was also related to lower methylation in LINE-1 at birth (-0.77; 95% CI: -1.52, -0.02; P = 0.044). Neither FA supplement use after 12 weeks of gestation nor maternal total folate intake (diet plus supplements) were associated with global DNA methylation levels at birth.

CONCLUSIONS

Maternal non-compliance with the use of FA supplement recommendations from preconception up to 12 weeks of gestation reduces offspring global DNA methylation levels at birth.

Perinatal, obstetric and parental risk factors for asthma in the offspring throughout childhood: a longitudinal cohort study

OBJECTIVES

Asthma is a common chronic and burdensome disease which typically begins in childhood. The aim of this study was to assess perinatal and obstetric factors which may increase the risk of developing asthma in the offspring.

METHODS

Data from five consecutive waves (n=7,073 children, from birth to 15 years old) from a nationally-representative birth cohort of people born in the United Kingdom between 2000 and 2002, the Millennium Cohort Study (MCS), were used. The Kaplan-Meier survival curve was used to graphically display the risk of developing asthma from early childhood to adolescence. The Z-based Wald test was used to prove significant covariate loading.

RESULTS

Cox regression analyzing the influence of covariates on asthma development risk showed a significant likelihood ratio test, χ2(18)=899.30, p<0.01. A parent with asthma (OR=2.02, p<0.01), a younger maternal age at delivery (OR=0.98, p<0.05), and the use of assisted reproductive technology (OR=1.43, p<0.05) were associated with an increased risk of developing asthma in the offspring.

CONCLUSIONS

Perinatal factors (a younger maternal age, assisted reproductive technology) and a parental factor (a parent with asthma) increased the risk for developing asthma in the offspring.

Does Asthma Disrupt Psychological Wellbeing in Pregnancy?

(1) Background: Asthma is a very prevalent disease with special characteristics during pregnancy, however, little is known about its relationship to the psychological wellbeing of women in this period; we aimed to know whether depression and anxiety symptoms are more frequent in asthmatic pregnant women. (2) Methods: Family Apgar (week 20), Edinburgh Postnatal Depression Scale (weeks 20 and 32) and State-Trait Anxiety Inventory (STAI) (week 32) tests were administered to 738 pregnant women (81 asthmatics) in the Nutrition in Early Life and Asthma (NELA) birth cohort. (3) Results: There were no significant differences between asthmatic and non-asthmatic pregnant women in any of the different tests at any of the time points. The mean scores for the different tests and timepoints between asthmatic and non-asthmatic pregnant women were: Apgar 20, 17.9 ± 2.2 vs. 10.0 ± 2.2; Edinburgh 20, 6.7 ± 4.2 vs. 6.9 ± 4.3; Edinburgh 32, 5.9 ± 4.4 vs. 5.6 ± 4.3; and STAI 32, 16.7 ± 8.4 vs. 15.8 ± 8.3. The proportion of pregnant women out of the normal range score for any of the tests and time points was also similar in both populations. (4) Conclusions: asthma is not associated with the psychological wellbeing of pregnant women.

Serum Vitamins A and E at Mid-Pregnancy and Their Relationships with Both Maternal and Cord Blood Antioxidant Status and Perinatal Conditions: The NELA Cohort

INTRODUCTION

Most of the pregnant women do not achieve the recommended dietary intake of vitamins A and E. These vitamins may counteract oxidative stress involved in some adverse perinatal outcomes. We aimed to assess the associations between maternal vitamin A and E at mid-pregnancy with both maternal and fetal outcomes and to identify possible early biomarkers during pregnancy to predict and prevent oxidative stress in the offspring.

METHODS

Data on dietary and serum levels of vitamins A and E were collected from 544 pregnant women from the Nutrition in Early Life and Asthma (NELA) study, a prospective mother-child cohort set up in Spain.

RESULTS

There were large discrepancies between low dietary vitamin E intake (78% of the mothers) and low serum vitamin E levels (3%) at 24 weeks of gestation. Maternal serum vitamins A and E at mid-pregnancy were associated with higher antioxidant status not only in the mother at this time point (lower hydroperoxides and higher total antioxidant activity [TAA]) but also with the newborn at birth (higher TAA). Gestational diabetes mellitus (GDM) was negatively associated with maternal serum vitamin A (OR: 0.95 CI: 0.91-0.99, p = 0.009) at mid-pregnancy. Nevertheless, we could not detect any association between GDM and oxidative stress parameters.

CONCLUSIONS

In conclusion, maternal vitamin A and E serum levels may be used as an early potential biomarker of antioxidant status of the neonate at birth. Control of these vitamins during pregnancy could help avoid morbid conditions in the newborn caused by oxidative stress in GDM pregnancies.

Cytokine production by newborns: influence of sex and season of birth

BACKGROUND

Immune signatures at birth could be associated with clinical outcomes and will improve our understanding of immunity prenatal programming.

METHODS

Data come from 235 newborns from the cohort study NELA. Production of cytokines was determined using Luminex technology. Associations between cytokine concentrations with sex and season of birth were examined by multivariate regression models.

RESULTS

Umbilical cord blood cells produced high levels of inflammatory cytokines, moderate levels of Th1/Th2/Tr-related cytokines, and low levels of Th17 cytokines. Compared to females, male newborn cells secreted higher levels of Th2 (peptidoglycan-stimulated IL-13, odds ratio [OR] = 2.26; 95% CI 1.18, 4.31, p value = 0.013) and Th17 (polyinosinic:polycytidylic acid-stimulated IL-23, OR = 1.82, 95% CI 1.01, 3.27, p value = 0.046) and lower levels of Th1 (olive-stimulated IL-2, OR = 0.56, 95% CI 0.31, 0.99, p value = 0.047) cytokines. Also, children born during warm seasons showed decreased innate cytokine response to peptidoglycan (IL-6, OR = 0.28, 95% CI 0.15, 0.52, p value < 0.001) compared to those born in cold seasons; meanwhile, adaptive immunity cytokines were more frequently secreted by children born during warm seasons in response to allergen extracts (IL-10, OR = 2.11, 95% CI 1.12, 3.96, p value = 0.020; IL-17F, OR = 3.31, 95% CI 1.83, 5.99, p value < 0.001).

CONCLUSION

Newborns showed specific cytokines signatures influenced by sex and season of birth.

IMPACT

There is a limited number of population-based studies on the immune status at birth and the influence of prenatal and perinatal factors on it. Characterization of cytokine signatures at birth related to the prenatal environment could improve our understanding of immunity prenatal programming. Newborns exhibit specific unstimulated and stimulated cytokine signatures influenced by sex and season of birth. Unstimulated and stimulated cytokine signatures in newborns may be associated with the development of related clinical outcomes later in life.

Maternal urinary concentrations of bisphenol A during pregnancy are associated with global DNA methylation in cord blood of newborns in the "NELA" birth cohort

Endocrine disrupting chemicals (EDCs) set a public health risk through disruption of normal physiological processes. The toxicoepigenetic mechanisms of developmental exposure to common EDCs, such as bisphenol A (BPA), are poorly known. The present study aimed to evaluate associations between perinatal maternal urinary concentrations of BPA, bisphenol S (BPS) and bisphenol F (BPF) and LINE-1 (long interspersed nuclear elements) and Alu (short interspersed nuclear elements, SINEs) DNA methylation levels in newborns, as surrogate markers of global DNA methylation. Data come from 318 mother-child pairs of the `Nutrition in Early Life and Asthma´ (NELA) birth cohort. Urinary bisphenol concentration was measured by dispersive liquid-liquid microextraction and ultrahigh performance liquid chromatography with tandem mass spectrometry detection. DNA methylation was quantitatively assessed by bisulphite pyrosequencing on 3 LINEs and 5 SINEs. Unadjusted linear regression analyses showed that higher concentration of maternal urinary BPA in 24th week's pregnancy was associated with an increase in LINE-1 methylation in all newborns (p = 0.01) and, particularly, in male newborns (p = 0.03). These associations remained in full adjusted models [beta = 0.09 (95 % CI = 0.03; 0.14) for all newborns; and beta = 0.10 (95 % CI = 0.03; 0.17) for males], including a non-linear association for female newborns as well (p-trend = 0.003). No associations were found between maternal concentrations of bisphenol and Alu sequences. Our results suggest that exposure to environmental levels of BPA may be associated with a modest increase in LINE-1 methylation -as a relevant marker of epigenomic stability- during human fetal development. However, any effects on global DNA methylation are likely to be small, and of uncertain biological significance.

Influence of Home Indoor Dampness Exposure on Volatile Organic Compounds in Exhaled Breath of Mothers and Their Infants: The NELA Birth Cohort

Currently, the effect of exposure to indoor air contaminants and the presence of dampness at home on respiratory/atopic health is of particular concern to physicians. The measurement of volatile organic compounds (VOCs) in exhaled breath is a useful approach for monitoring environmental exposures. A great advantage of this strategy is that it allows the study of the impact of pollutants on the metabolism through a non-invasive method. In this paper, the levels of nine VOCs (acetone, isoprene, toluene, p/m-xylene, o-xylene, styrene, benzaldehyde, naphthalene, and 2-ethyl-1-hexanol) in the exhaled breath of subjects exposed and not exposed to home dampness were assessed. Exhaled breath samples were collected from 337 mother–child pairs of a birth cohort and analysed by gas-chromatography–mass-spectrometry. It was observed that the levels of 2-ethyl-1-hexanol in the exhaled breath of the mothers were significantly influenced by exposure to household humidity. In the case of the infants, differences in some of the VOC levels related to home dampness exposure; however, they did not reach statistical significance. In addition, it was also found that the eosinophil counts of the mothers exposed to home dampness were significantly elevated compared to those of the non-exposed mothers. To our knowledge, these findings show, for the first time, that exposure to home dampness may influence VOC patterns in exhaled breath.

Dietary Patterns in Pregnancy and Biomarkers of Oxidative Stress in Mothers and Offspring: The NELA Birth Cohort

Background

Although adherence to the Mediterranean and antioxidant-rich diets during pregnancy is suggested to improve maternal-fetal health by reducing oxidative stress, yet there is no study available.

Objective

We examined whether maternal dietary patterns in pregnancy impact the biomarkers of oxidative stress in mothers and their offspring.

Methods

Study population included 642 mothers and 335 newborns of the "Nutrition in Early Life and Asthma" (NELA) birth cohort. Maternal diet during pregnancy was assessed by a validated food frequency questionnaire and a priori-defined dietary indices (relative Mediterranean Diet [rMED], alternative Mediterranean Diet [aMED], Dietary Approach to Stop Hypertension [DASH], Alternate Healthy Index [AHEI], and AHEI-2010) were calculated. Biomarkers measured were: hydroperoxides, carbonyl groups, and 8-hydroxydeoxyguanosine (8OHdG) determined in maternal blood and newborn cord blood, and urinary maternal and offspring 15-F2t-isoprostane. Multivariate linear regression models were performed.

Results

Maternal rMED score was inversely associated with the maternal levels of 8OHdG at mid-pregnancy (beta per 1-point increase = -1.61; 95% CI -2.82, -0.39) and the newborn levels of hydroperoxides (beta per 1-point increase = -4.54; 95% CI -9.32, 0.25). High vs. low maternal rMED score was marginally associated with the decreased levels of 8OHdG in newborns (beta = -9.17; 95% CI -19.9, 1.63; p for trend 0.079). Maternal DASH score tended to be inversely associated with maternal urinary 15-F2t-isoprostane (beta per 1-point increase = -0.69; 95% CI, -1.44, 0.06). High vs. low maternal AHEI score was associated with reduced offspring urinary levels of 15-F2t-isoprostane (beta = -20.2; 95% CI -38.0, -2.46; p for trend 0.026).

Conclusion

These results suggest that maternal adherence to healthy dietary patterns during pregnancy may reduce DNA damage and lipid oxidation in mothers and offspring.

Cytokine profiles in cord blood in relation to prenatal traffic-related air pollution: The NELA cohort

BACKGROUND

Outdoor air pollution may disturb immune system development. We investigated whether gestational exposure to traffic-related air pollutants (TRAP) is associated with unstimulated cytokine profiles in newborns.

METHODS

Data come from 235 newborns of the NELA cohort. Innate response-related cytokines (IL-6, IFN-α, IL1-β, and TNF-α), Th1-related (IFN-γ and IL-2), Th2-related (IL-4, IL-5, and IL-13), Th17-related (IL-17 and IL-23), and immunomodulatory cytokine IL-10 were quantified in the supernatant of unstimulated whole umbilical cord blood cells after 7 days of culture using the Luminex technology. Dispersion/chemical transport modeling was used to estimate long-term (whole pregnancy and trimesters) and short-term (15 days before delivery) residential exposures to traffic-related nitrogen dioxide (NO₂ ), particulate matter (PM_2.5 and PM₁₀ ), and ozone (O₃ ). We fitted multivariable logistic regression, Bayesian kernel machine regression (BKMR), and weighted quantile sum (WQS) regression models.

RESULTS

NO₂ during the whole pregnancy increased the odds of detection of IL-1β (OR per 10 µg/m³ increase = 1.37; 95% CI, 1.02, 1.85) and IL-6 (OR per 10 µg/m³ increase = 1.32; 95% CI 1.00, 1.75). Increased odds of detected concentrations of IL-10 was found in newborns exposed during whole pregnancy to higher levels of NO₂ (OR per 10 µg/m³ increase = 1.30; 95% CI 0.99, 1.69), PM₁₀ (OR per 10 µg/m³ increase = 1.49; 95% CI 0.95, 2.33), and PM_2.5 (OR per 5 µg/m³ increase = 1.56; 95% CI 0.97, 2.51). Exposure to O₃ during the whole pregnancy increased the odds of detected IL-13 (OR per 10 µg/m³ increase = 1.22; 95% CI 1.01, 1.49). WQS model revealed first and third trimesters of gestation as windows of higher susceptibility.

CONCLUSIONS

Gestational exposure to TRAP may increase detection of pro-inflammatory, Th2-related, and T regulatory cytokines in newborns. These changes might influence immune system responses later in life.