Fatty acids in colostrum from mothers of children at high risk of atopy in relation to clinical and laboratory signs of allergy in the first year of life

Oropharyngeal administration of colostrum targeting gut microbiota and metabolites in very preterm infants: protocol for a multicenter randomized controlled trial

BACKGROUND

Oropharyngeal administration of colostrum (OAC) has an immune-stimulating effect on oropharyngeal-associated lymphoid tissue, and can promote the maturation of the gastrointestinal tract. However, how OAC promotes intestinal maturation in preterm infants by altering gut microbiota remains unclear. We aim to assess changes in gut microbiota and metabolites after OAC in very preterm infants.

METHODS

A multicenter, double-blind, randomized controlled trial will be conducted in three large neonatal intensive care units in Shenzhen, China, with preterm infants with gestational age less than 32 weeks at birth and birth weight less than 1500 g. It is estimated that 320 preterm infants will be enrolled in this study within one year. The intervention group will receive oropharyngeal administration of 0.2 ml colostrum every 3 h, starting between the first 48 to 72 h and continued for 5 consecutive days. Following a similar administration scheme, the control group will receive oropharyngeal administration of sterile water. Stool samples will be collected at the first defecation, as well as on the 7th, 14th, 21st and 28th days after birth for analysis of effect of OAC on gut microbiota and metabolites through 16sRNA gene sequencing and liquid chromatography-mass spectrometry.

DISCUSSION

This proposal advocates for the promotion of OAC as a safe and relatively beneficial protocol in neonatal intensive care units, which may contribute to the establishment of a dominant intestinal flora. Findings of this study may help improve the health outcomes of preterm infants by establishment of targeted gut microbiota in future studies.

TRIAL REGISTRATION

NCT05481866 (registered July 30, 2022 on ClinicalTrials.gov).

The causal association of polyunsaturated fatty acids with allergic disease: A two-sample Mendelian randomization study

Objectives

Previous studies have reported a potential association of polyunsaturated fatty acids (PUFAs) levels with allergic disease risk and the possible benefit of PUFAs supplementation on allergic disease prevention. This study was performed to estimate the genetic association between PUFAs and allergic diseases using the method of both univariable and multivariable two-sample Mendelian randomization (MR).

Methods

As indicators of the PUFAs levels, we included the omega-3, omega-6, docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), linoleic acid (LA), and the ratio of omega-6 to omega-3 (omega-6:3). Summarized statistics of genome-wide association studies (GWASs) for these PUFAs were obtained from the United Kingdom Biobank and the Twins United Kingdom cohort. Genetic data relating to allergic diseases, including atopic dermatitis (AD), allergic rhinitis (AR), allergic conjunctivitis (AC), allergic urticaria (AU) and asthma, were accessed from the FinnGen biobank analysis. Odds ratios and 95% CIs were used to express the impact.

Results

The MR results denoted a genetic association between the genetically determined increase in omega-3 levels and the decreased risk of some allergic diseases including AD (OR: 0.863; 95% CI: 0.785 to 0.949; p = 3.86E-03), AC (OR:0.720; 95% CI: 0.547 to 0.947; p = 1.87E-02) and AU (OR:0.821; 95% CI: 0.684 to 0.985; p = 3.42E-02), while omega-6 and DHA level was only found to have negatively correlation with risk of AC with ORs of 0.655 (95% CI: 0.445 to 0.964; p = 3.18E-02) and 0.671 (95% CI 0.490 to 0.918; p = 1.25E-02), respectively. Omega-6:3 were causally significantly associated with the increased risk of AD (OR:1.171; 95% CI: 1.045 to 1.312; p = 6.46E-03) and AC (IVW: OR:1.341; 95% CI: 1.032 to 1.743; p = 2.83E-02). After adjustment of age, economic level, BMI, smoking and alcohol behaviors in the multivariable MR analysis, a direct causal protective effect of omega-3 on AD and AC, as well as a direct causal association between DHA and AD were observed. Omega-6:3 was also found to be directly associated with an increased risk of AD and AC. No association was found of EPA or LA with allergic diseases.

Conclusion

Higher PUFA concentrations (omega-3, omega-6, DHA) and lower omega-6:3 ratios were genetically associated with a lower risk of some allergic diseases.

Perspective: Moving Toward Desirable Linoleic Acid Content in Infant Formula

Infant formula should provide the appropriate nutrients and adequate energy to facilitate healthy infant growth and development. If conclusive data on quantitative nutrient requirements are not available, the composition of human milk (HM) can provide some initial guidance on the infant formula composition. This paper provides a narrative review of the current knowledge, unresolved questions, and future research needs in the area of HM fatty acid (FA) composition, with a particular focus on exploring appropriate intake levels of the essential FA linoleic acid (LA) in infant formula. The paper highlights a clear gap in clinical evidence as to the impact of LA levels in HM or formula on infant outcomes, such as growth, development, and long-term health. The available preclinical information suggests potential disadvantages of high LA intake in the early postnatal period. We recommend performing well-designed clinical intervention trials to create clarity on optimal levels of LA to achieve positive impacts on both short-term growth and development and long-term functional health outcomes.

β-Glucosylceramide From Allergic Mothers Enhances Offspring Responsiveness to Allergen

In animals and humans, offspring of allergic mothers have increased responsiveness to allergen and the allergen-specificity of the offspring can be different than that of the mother. In our preclinical models, the mother's allergic responses influence development of the fetus and offspring by elevating numbers of cells in dendritic cell subsets. A major question is the identity of maternal factors of allergic mothers that alter offspring development of responsiveness to allergen. Lipids are altered during allergic responses and lipids are transported to the fetus for growth and formation of fetal membranes. We hypothesized that pro-inflammatory lipids, that are elevated in allergic mothers, are transported to the fetus and regulate fetal immune development. We demonstrate in this report that there was a significant 2-fold increase in β-glucosylceramides (βGlcCer) in allergic mothers, the fetal liver and her offspring. The βGlcCer were transported from mother's plasma, across the placenta, to the fetus and in breastmilk to the offspring. Administration of βGlcCer to non-allergic mothers was sufficient for offspring responses to allergen. Importantly, maternal administration of a clinically relevant pharmacological inhibitor of βGlcCer synthase returned βGlcCer to normal levels in the allergic mothers and her offspring and blocked the offspring increase in dendritic cell subsets and offspring allergen responsiveness. In summary, allergic mothers had increased βGlcCer that was transported to offspring and mediated increases in offspring DCs and responsiveness to allergen. These data have a significant impact on our understanding of mechanisms for development of allergies in offspring of allergic mothers and have the potential to lead to novel interventions that significantly impact risk for allergic disease early in life.

Immunologically Active Components in Human Milk and Development of Atopic Disease, With Emphasis on Food Allergy, in the Pediatric Population

Breast-feeding is currently recommended to prevent the development of allergic diseases; however, data are conflicting and mechanisms are unclear. The immunomodulatory composition of human milk is poorly characterized and varies between mothers. We and others have shown that high levels of human milk IgA and certain cytokines and human milk oligosaccharides are associated with protection against food allergy in the infant, but it is unclear whether they are responsible for or simply biomarkers of the vertical transfer of protection. Because human milk has pre- and probiotic properties, the anti-allergy protection afforded by human milk may be due to its control on the developing gut microbiome. In mice, murine milk IgA supports gut homeostasis and shapes the microbiota, which in turn diversifies the intestinal IgA repertoire that reciprocally promotes the diversity of gut microbiome; these mechanisms are poorly understood in humans. In addition, several human milk bioactives are immunostimulatory, which may in part provide protection against allergic diseases. The regulation of immunologically active components in human milk is incompletely understood, although accumulating evidence suggests that IgA and cytokines in human milk reflect maternal exposures. This review summarizes the current literature on human milk components that have been associated with protection against food allergy and related allergic disorders in early childhood and discusses the work relating to regulation of these levels in human milk and possible mechanisms of action.

Association of breast milk fatty acids with allergic disease outcomes-A systematic review

INTRODUCTION

Dietary polyunsaturated fatty acids (PUFAs) have immunoregulatory properties. Breast milk is rich in PUFA, and it has been hypothesized that these PUFAs may be important in the aetiology of allergic diseases. Despite a growing body of evidence, the associations between breast milk PUFA and allergic disease have not previously been systematically reviewed.

METHODS

The search was performed in PubMed and EMBASE databases using breastfeeding, fatty acid and allergic disease terms. Two authors were involved in selecting papers for review according to the inclusion criteria and extracting information on study characteristics and measures of association. Only studies that reported numeric associations between concentration of breast milk fatty acids and allergic disease outcomes were included.

RESULTS

A total of 18 papers met the inclusion criteria, reporting results from 15 study populations. The majority were cohort studies (n=11), with data from only two case-control and two cross-sectional studies. Sample size varied between 30 and 352 participants, and follow-up time of the cohorts varied between 3 months and 14 years. Nine studies reported on eczema, seven reported on sensitization, and only five reported on asthma/wheeze. There was heterogeneity among studies in terms of presenting the association between PUFA and allergy; therefore, estimates could not be pooled. Only a few studies observed associations between n-3 and n-6 PUFAs and allergic disease, and the magnitude of this effect varied greatly.

CONCLUSIONS

There is insufficient evidence to suggest that colostrum or breast milk polyunsaturated fatty acids influence the risk of childhood allergic diseases.

They Are What You Eat: Can Nutritional Factors during Gestation and Early Infancy Modulate the Neonatal Immune Response?

The ontogeny of the human immune system is sensitive to nutrition even in the very early embryo, with both deficiency and excess of macro- and micronutrients being potentially detrimental. Neonates are particularly vulnerable to infectious disease due to the immaturity of the immune system and modulation of nutritional immunity may play a role in this sensitivity. This review examines whether nutrition around the time of conception, throughout pregnancy, and in early neonatal life may impact on the developing infant immune system.

Breast milk polyunsaturated fatty acids: associations with adolescent allergic disease and lung function

BACKGROUND

It has been hypothesized that n-3 PUFA in breast milk may assist immune and lung development. There are very limited data on possible long-term effects on allergic disease and lung function. The aim was to investigate associations of n-3 and n-6 PUFA levels in colostrum and breast milk with allergic disease and lung function at ages 12 and 18 years.

METHODS

Polyunsaturated fatty acids were measured in 194 colostrum samples and in 118 three-month expressed breast milk samples from mothers of children enrolled in the Melbourne Atopy Cohort (MACS) Study, a high-risk birth cohort study. Associations with allergic diseases, skin prick tests and lung function assessed at 12 and 18 years were estimated using multivariable regression.

RESULTS

Higher levels of n-3 but not n-6 PUFAs in colostrum were associated with a trend towards increased odds of allergic diseases, with strong associations observed for allergic rhinitis at 12 (OR = 5.69[95% CI: 1.83,17.60] per weight%) and 18 years (4.43[1.46,13.39]) and eczema at 18 years (9.89[1.44, 68.49]). Higher levels of colostrum n-3 PUFAs were associated with reduced sensitization (3.37[1.18, 9.6]), mean FEV₁ (-166 ml [-332, -1]) and FEV₁ /FVC ratio (-4.6%, [-8.1, -1.1]) at 12 years.

CONCLUSION

Higher levels of colostrum n-3 PUFAs were associated with increased risks of allergic rhinitis and eczema up to 18 years, and sensitization and reduced lung function at 12 years. As residual confounding may have caused these associations, they should be replicated, but these results could indicate that strategies that increase maternal n-3 PUFA intake may not aid in allergic disease prevention.

Breastmilk fatty acids in relation to sensitization - the ALADDIN birth cohort

BACKGROUND

Breastmilk fatty acids (FAs) have been associated with childhood allergic disease. Children of families with an anthroposophic lifestyle have a low prevalence of sensitization compared to reference groups. This study aimed to investigate whether the lower prevalence of sensitization among these children can be explained by the differences in breastmilk FA composition.

METHODS

The prospective birth cohort ALADDIN included 330 children from anthroposophic, partly anthroposophic and nonanthroposophic families recruited between 2004 and 2007 in Sweden. In total, 245 breastmilk samples, collected at 2 months of age, were analysed for FA composition. Allergen-specific IgE levels against seven common allergens were measured in the blood samples at the ages of 6, 12 and 24 months. Data were analysed longitudinally using generalized estimating equations.

RESULTS

An inverse association was observed between total concentration of omega-3 PUFA in breastmilk and sensitization in the child up to 24 months of age (highest vs lowest quartile, RRadj 0. 49, 95% CI 0.23-1.05, P for trend 0.024). No associations were observed between omega-6 PUFAs or ruminant FAs and sensitization. Overall, we observed 56% lower risks of sensitization among the anthroposophic group compared to the nonanthroposophic group (RRadj 0.44, 95% CI 0.21-0.90). This association remained largely unchanged when breastmilk omega-3 PUFA was included in the model.

CONCLUSION

Our results indicate that a higher concentration of omega-3 PUFAs in breastmilk may be associated with a reduced risk of sensitization up to 24 months of age; however, this did not explain the lower risk of sensitization among children of anthroposophic families.

Factors affecting breast milk composition and potential consequences for development of the allergic phenotype

There is conflicting evidence on the protective role of breastfeeding in relation to allergic sensitization and disease. The factors in breast milk which influence these processes are still unclear and under investigation. We know that colostrum and breast milk contain a variety of molecules which can influence immune responses in the gut-associated lymphoid tissue of a neonate. This review summarizes the evidence that variations in colostrum and breast milk composition can influence allergic outcomes in the infant, and the evidence that maternal and environmental factors can modify milk composition. Taken together, the data presented support the possibility that maternal dietary interventions may be an effective way to promote infant health through modification of breast milk composition.

Breast milk fatty acid composition has a long-term effect on the risk of asthma, eczema, and sensitization

BACKGROUND

Levels of n-3 polyunsaturated fatty acids (PUFAs) and n-6 PUFAs in breast milk are associated with the development of allergic diseases up to school age. However, it is unknown whether this relationship persists when the child becomes older. We therefore studied the association between levels of n-3 PUFAs and n-6 PUFAs in breast milk of allergic- and nonallergic mothers and asthma, eczema and sensitization up to the age of 14 years.

METHODS

The study was nested in the ongoing PIAMA birth cohort. At the child's age of 3 months, 276 mothers provided a breast milk sample. Asthma (N total = 269) and eczema (N total = 274) were self-reported up to the child's age of 14 years. Specific serum IgE levels were measured at the ages of 4, 8 and 12 years (N total = 216). Generalized estimating equations analyses were used to take account of repeated observations.

RESULTS

Asthma up to the age of 14 years is less prevalent in children of allergic mothers receiving breast milk with higher levels of n-3 long chain polyunsaturated (LCP) fatty acids (OR 0.50; 95% CI 0.31-0.79), and more prevalent in children of nonallergic mothers receiving breast milk with higher levels of n-6LCP (OR 1.86; 95% CI 1.14-3.03). Weaker associations in similar direction were observed for eczema and sensitization. Direction of associations were consistent and of similar magnitude throughout childhood.

CONCLUSION

The association between breast milk fatty acid composition and asthma, eczema and sensitization persists up to the age of 14 years in children of both allergic and nonallergic mothers.

Maternal influences over offspring allergic responses

Asthma occurs as a result of complex interactions of environmental and genetic factors. Clinical studies and animal models of asthma indicate offspring of allergic mothers have increased risk of development of allergies. Environmental factors including stress-induced corticosterone and vitamin E isoforms during pregnancy regulate the risk for offspring development of allergy. In this review, we discuss mechanisms for the development of allergic disease early in life, environmental factors that may impact the development of risk for allergic disease early in life, and how the variation in global prevalence of asthma may be explained, at least in part, by some environmental components.

Asthma and allergic diseases in pregnancy a review

Asthma and allergic disorders can affect the course and outcome of pregnancy. Pregnancy itself may also affect the course of asthma and related diseases. Optimal management of these disorders during pregnancy is vital to ensure the welfare of the mother and the baby.

Specific pharmacological agents for treatment of asthma or allergic diseases must be cautiously selected and are discussed here with respect to safety considerations in pregnancy. Although most drugs do not harm the fetus, this knowledge is incomplete. Any drug may carry a small risk that must be balanced against the benefits of keeping the mother and baby healthy. The goals and principles of management for acute and chronic asthma, rhinitis, and dermatologic disorders are the same during pregnancy as those for asthma in the general population.

Diagnosis of allergy during pregnancy should mainly consist of the patient's history and in vitro testing.

The assured and well-evaluated risk factors revealed for sensitization in mother and child are very limited, to date, and include alcohol consumption, exposure to tobacco smoke, maternal diet and diet of the newborn, drug usage, and insufficient exposure to environmental bacteria. Consequently, the recommendations for primary and secondary preventive measures are also very limited in number and verification.

Fatty-acid composition of maternal and umbilical cord plasma and early childhood atopic eczema in a Spanish cohort

BACKGROUND/OBJECTIVES

Fatty-acid status during in-utero development might influence the risk of atopic diseases in early childhood. The aim of this work was to identify the relationship between maternal plasma and cord blood fatty acid (FA) composition and the risk of atopic eczema in the offspring at 14 months of age.

SUBJECTS/METHODS

Two hundred and eleven non-atopic mothers and their children were studied. Mothers were recruited in their first trimester of gestation and children were monitored until 14 months of age. Samples of maternal plasma and cord blood plasma were analyzed to determine the FA profile of total lipids. Presence of atopic eczema in the infants was documented through questionnaires at 6 and 14 months of age.

RESULTS

Higher concentrations of total long-chain polyunsaturated FA (LC-PUFA) were found in maternal plasma of non-atopic children in relation to atopic group. Moreover, this maternal plasma LC-PUFA content was negatively correlated with the atopic eczema (odds ratios (OR)=0.83, P=0.04) in infants. Regarding cord blood samples, docosahexaenoic acid (DHA C22:6n3) and the sum of total n-3 and of LC-PUFA n-3 showed a negative correlation with the prevalence of the disease (OR=0.50, 0.49 and 0.49, respectively).

CONCLUSIONS

Our results show that the fatty-acid status of the fetus during pregnancy has an important role in the development of atopic eczema in early childhood. The prevalence of this atopic disorder is related to lower cord blood plasma levels of FA belonging to n-3 series, especially DHA.

Maternal fatty acid status in pregnancy and childhood atopic manifestations: KOALA Birth Cohort Study

BACKGROUND

Prevalence of atopic disorders has increased rapidly, but aetiological factors responsible for this increase are still largely unknown. Prenatal exposure to a pro-inflammatory fatty acid status is hypothesized although little research has been carried out.

OBJECTIVE

To investigate whether prenatal fatty acid exposures are associated with atopy in childhood.

METHODS

In the KOALA Birth Cohort Study, maternal blood samples (n=1275) at 34-36 weeks of pregnancy were assayed for n-6 and n-3 long-chain polyunsaturated fatty acids (LCPs). The full spectrum of offspring atopic manifestations (wheeze, asthma, allergic rhinoconjunctivitis, eczema, atopic dermatitis, allergic sensitization, and high total IgE) until the age of 6-7 years was assessed by repeated parental questionnaires and measurements of total and specific IgE. Associations of maternal fatty acid status with child atopic outcomes were analysed using multivariable logistic regression and generalized estimating equations for repeated measurements.

RESULTS

High ratio of maternal n-6 vs. n-3 LCPs was associated with a lower risk of eczema in the child (P for trend 0.012). More specifically, we found a decreased risk of eczema in the first 7 months of life with increasing arachidonic acid levels (P for trend 0.013). No associations were found between maternal fatty acids and offspring airway-related atopic manifestations, sensitization, or high total IgE.

CONCLUSION AND CLINICAL RELEVANCE

The development of atopic disorders in early childhood is associated with prenatal exposure to n-6 vs. n-3 fatty acids, but with inconsistencies between different manifestations. Further exploration of associations with maternal diet and genetic variants in genes regulating fatty acid metabolism are required. This study shows that the influence of prenatal exposure to fatty acids on the risk of eczema in the child is limited to the first year of life.

Linseed oil in the maternal diet increases long chain-PUFA status of the foetus and the newborn during the suckling period in pigs

Linseed oil, being rich in 18 : 3n-3, represents an alternative source of n-3 PUFA in the maternal diet. However, little is known about the effect of this oil on the long chain n-3 PUFA composition of offspring, which are required for normal growth and maturation of numerous organs. The main objective of the experiment was therefore to investigate fatty acid composition of tissues from sows at the end of gestation and from piglets during the first week of postnatal life in response to maternal dietary linseed oil intake. Sows received either a lard (LAR)-based diet or a linseed oil (LSO)-based diet during gestation and lactation. Fatty acid composition was evaluated in sow plasma, placenta and milk, and in different tissues of piglets on days 0, 3, 7, 21 and 32. The LSO diet increased the proportions of n-3 PUFA and especially 22 : 6n-3 in the placenta. The carcass of LSO piglets at birth contained greater proportions of 20 : 5n-3, 22 : 5n-3 and 22 : 6n-3. The LSO sow milk exhibited greater proportions of 18 : 3n-3 compared with the LAR sow milk. The piglets suckling LSO sows had greater proportions of 18 : 3n-3, 20 : 5n-3 and 22 : 5n-3 in plasma and carcass. The proportions of 22 : 5n-3 and 22 : 6n-3 were greater in the brain of LSO piglets than in that of LAR piglets during the suckling period. In conclusion, LSO in the maternal diet during gestation and lactation increases 22 : 6n-3 concentrations in the placenta and in the foetus carcass, and it maintains 22 : 6n-3 concentrations in the brain during the first week of postnatal life.

Asthma and allergic diseases in pregnancy a review

Asthma and allergic disorders can affect the course and outcome of pregnancy. Pregnancy itself may also affect the course of asthma and related diseases. Optimal management of these disorders during pregnancy is vital to ensure the welfare of the mother and the baby.Specific pharmacological agents for treatment of asthma or allergic diseases must be cautiously selected and are discussed here with respect to safety considerations in pregnancy. Although most drugs do not harm the fetus, this knowledge is incomplete. Any drug may carry a small risk that must be balanced against the benefits of keeping the mother and baby healthy. The goals and principles of management for acute and chronic asthma, rhinitis, and dermatologic disorders are the same during pregnancy as those for asthma in the general population.Diagnosis of allergy during pregnancy should mainly consist of the patient's history and in vitro testing.The assured and well-evaluated risk factors revealed for sensitization in mother and child are very limited, to date, and include alcohol consumption, exposure to tobacco smoke, maternal diet and diet of the newborn, drug usage, and insufficient exposure to environmental bacteria. Consequently, the recommendations for primary and secondary preventive measures are also very limited in number and verification.

Maternal transmission of asthma risk

Maternal asthma significantly increases the risk of asthma in offspring, but the mechanisms remain poorly defined. We review animal models used to study the maternal effect, focusing on a murine model developed in our laboratory. Mother mice rendered allergic to ovalbumin produce offspring that are more susceptible to allergic sensitization, seen as airway hyperresponsiveness and allergic airway inflammation after a sensitization protocol, which has minimal effects on newborns from normal mothers. Mechanistic analyses identify a role for interleukin-4 (based on pre-mating injection of neutralizing antibodies), dendritic cells and allergen-specific T cells (based on adoptive transfer experiments). Other maternal exposures (e.g. pollutant exposure and non-pulmonary allergy) can increase asthma susceptibility in offspring. This observation implies that the maternal transmission of asthma represents a final common pathway to various types of inflammatory stimuli. Identification of the shared molecular mechanisms in these models may allow better prevention and therapy. Current knowledge, gaps in knowledge and future directions are discussed.

Impact of PUFA on early immune and fetal development

It has recently been reported that the increased prevalence in childhood allergy may be linked to deviations in fetal immune development. One reason may be impaired nutrient supply. Hence, a well-differentiated placenta together with an optimal fetal nutrition via the mother are important prerequisites for the establishment of a functional immune system with normal immune responses. Fatty acids and their derivatives can influence both the early immune development and immune maturation by regulating numerous metabolic processes and the gene expression of important proteins such as enzymes and cytokines. The present review summarises the impact of nutritional fatty acids on the development of the immune system as well as the fetal development. It describes the mechanisms of action of PUFA, trans fatty acids and conjugated linoleic acids in programming the fetus with regard to its risk of acquiring atopic diseases in childhood.

Association between first-degree familial predisposition of asthma and atopy (total IgE) in newborns

BACKGROUND

It is generally thought that infants with a first-degree familial predisposition of asthma are at higher risk of developing asthma than infants without predisposition.

OBJECTIVE

To investigate whether there is an association between being at high risk for developing asthma and increased level of total IgE in newborns and whether total IgE is influenced by gender, family size, birth season, maternal smoking, birth weight, gestational age, and maternal diet.

METHODS

Two hundred and twenty-one high risk and 308 low-risk infants were prenatally selected in a 5-year-period. Three to 5 days after birth, the total IgE was measured in capillary heel blood.

RESULTS

Data on total IgE and first-degree familial predisposition were available for 170 high-risk and 300 low-risk infants. There was a statistically significant relationship between being at high-risk (maternal asthma) and increased levels of total IgE in newborns (total IgE cut-off levels: 0.6-0.9 IU/mL (odds ratio (OR)=2.1, 95% confidence interval (CI): 1.2-3.7 to 3.0, 95% CI: 1.5-5.9)), between being born in autumn and increased levels of total IgE in newborns [total IgE cut-off levels: 0.5-0.6 IU/mL (OR=2.5, 95% CI: 1.2-5.1 to 2.5, 95% CI: 1.2-5.4)] and between maternal vitamin supplements intake and decreased levels of total IgE in newborns (total IgE cut-off level: 0.9 IU/mL (OR=0.5, 95% CI:0.3-1.0)). There was no interaction between the effects of maternal asthma and birth season on total IgE, as well as between the effects of maternal asthma and maternal vitamin supplements intake. Gender, family size, maternal smoking, birth weight, and gestational age did not influence the associations. CONCLUSION; Being at high-risk of asthma (maternal asthma) and birth season are positively associated with the presence of increased levels of total IgE at birth, whereas maternal vitamin supplements intake is negatively associated with the presence of total IgE at birth.

Serum, cheek cell and breast milk fatty acid compositions in infants with atopic and non-atopic eczema

BACKGROUND

The major theory implicating diet with allergic diseases is associated with altered food consumption and subsequent changes in fatty acid composition.

OBJECTIVE

To investigate fatty acid compositions among infants with atopic and non-atopic eczema and healthy infants and to evaluate the expediency of non-invasive cheek cell phospholipid fatty acid composition as a marker in patients with eczema.

METHODS

Diagnosis of eczema in infants was confirmed clinically and by positive (atopic eczema, n=6) or negative (non-atopic eczema, n=6) skin prick testing in comparison with controls (n=19). The fatty acid compositions of infant cheek cell and serum phospholipids and breast milk total lipids were analysed by gas chromatography.

RESULTS

The distinction between atopic and non-atopic eczema was manifested in cheek cell phospholipids as linoleic acid (14.69 (13.67-15.53)% of total fatty acids; the median (interquartile range)), the sum of n-6 fatty acids (19.94 (19.06-20.53)%) and the sum of polyunsaturated fatty acids (22.70 (21.31-23.28)%) were higher in infants with atopic eczema compared with non-atopic eczema (12.69 (10.87-13.93); 17.72 (15.63-18.91) and 19.90 (17.64-21.06), respectively; P<0.05) and controls (12.50 (12.16-13.42); 18.19 (17.43-18.70) and 20.32 (19.32-21.03), respectively; P<0.05). Serum phospholipid gamma-linolenic acid was lower in both atopic and non-atopic eczema compared with controls (P<0.05) and additionally eicosapentaenoic acid was higher in atopic eczema compared with controls (P<0.05).

CONCLUSION

These preliminary results suggest differences in fatty acid compositions between the two types of eczema, calling for further evaluation in a larger setting. The two types of eczema may be regulated by different immunological processes, and fatty acids may have a more profound role in the atopic type.

Fatty acid composition of human milk in atopic Danish mothers

BACKGROUND

Atopic dermatitis has been related to a disturbed metabolism of polyunsaturated fatty acids (PUFAs).

OBJECTIVE

We tested whether the PUFA composition of breast milk differs significantly between mothers with atopic dermatitis, mothers with other types of atopy, and nonatopic mothers. We also investigated whether differences in diet can explain possible observed differences.

DESIGN

Mothers with current or previous asthma (n = 396) were divided into 3 groups according to history of atopic dermatitis and allergic rhinitis. Breast-milk samples were collected from 314 women approximately 3 wk after delivery. The habitual diet of the women was assessed with food-frequency questionnaires in the 25th week of gestation (n = 207). Breast-milk samples and simultaneous dietary data from 14 nonatopic mothers were used for comparison.

RESULTS

Compared with the milk of nonatopic mothers, that of atopic mothers had significantly higher concentrations of 22:5n-6 and lower concentrations of 20:5n-3; moreover, 20:4n-6/20:5n-3, 22:5n-6/22:6n-3, and long-chain n-3 PUFA/18:3n-3 were shifted toward n-6 PUFA and 18:3n-3 in nonatopic and atopic mothers, respectively. No differences in breast-milk PUFA composition were evident between the subject groups. The diets of the groups differed only slightly with respect to protein intake. However, the PUFA composition of the breast milk was associated with diet and time of milk sampling, and the above difference in milk PUFAs disappeared when those factors were taken into account.

CONCLUSION

Our data do not support the possibility that the fatty acid composition of breast milk is affected by atopic dermatitis or atopy in general, because most differences in breast-milk PUFA composition appear to be explained by the diet.

Breast milk fatty acids may link innate and adaptive immune regulation: analysis of soluble CD14, prostaglandin E2, and fatty acids

In addition to its role in sensing intraluminal microbial antigens, soluble (s)CD14 may regulate immune responses by its lesser known function as a lipid carrier with possible influences in the production of fatty acid-derived eicosanoids. We investigated the interrelations of fatty acids, prostaglandin E2 (PGE2), and sCD14 and their role in infant atopic eczema during the first year of life. Serum and breast milk samples from mothers and serum samples from their infants were collected at infant's age 3 mo and analyzed for sCD14 and PGE2 concentrations and for fatty acid compositions. The main correlation of sCD14 was with arachidonic acid (20:4n-6) (AA). Dihomo-gamma-linolenic acid (20:3n-6) (DHGLA) and the ratio of n-6 to n-3 fatty acids correlated positively and docosahexaenoic acid (22:6n-3) (DHA) and sum of n-3 fatty acid negatively with PGE2 in mother's serum and linoleic acid (LA) negatively with PGE2 in breast milk. Soluble CD14 tended to be higher and LA, total polyunsaturated fatty acid (PUFA), and sum of n-6 fatty acids were lower in breast milk received by infants with atopic eczema compared with those without. These results suggest that fatty acids contribute to the regulation of innate and adaptive immune responses and link intraluminal exposures, mother's diet, and microbes.

Breast milk fatty acids and allergic disease in preschool children: the Prevention and Incidence of Asthma and Mite Allergy birth cohort study

BACKGROUND

Better understanding of the association between early life lipid intakes and the development of allergic diseases is needed.

OBJECTIVE

We prospectively studied breast milk content of n-6, n-3, and trans fatty acids in relation to allergic symptoms at the ages of 1 and 4 years.

METHODS

Fatty acid content was determined in breast milk samples of 265 (158 allergic and 107 nonallergic) mothers of children participating in the Prevention and Incidence of Asthma and Mite Allergy study. Outcome variables studied were parental reported eczema at age 1 year, eczema at age 4 years, asthma at age 4 years, and, in a subgroup of 133 children, sensitization at age 4 years.

RESULTS

In children of mothers with allergy, breast milk n-3 long chain polyunsaturated fatty acids and the ratio between n-3 and n-6 long chain polyunsaturated fatty acids were inversely associated with asthma and with persistent symptoms (eczema at age 1 year and eczema at age 4 years and/or asthma at age 4 years), but no associations between breast milk fatty acids and sensitization were observed. In children of mothers with allergy, also trans fatty acids tended to be inversely associated with allergic symptoms. In children of mothers without allergy, no associations between breast milk fatty acids and allergic symptoms were observed, but alpha-linolenic acid (18:3n-3) was positively associated with sensitization.

CONCLUSION

In susceptible infants, the risk to develop allergic symptoms, but not the risk of sensitization, was modified by intake of n-3 long chain polyunsaturated fatty acids through breast milk.

Role of breast milk in a mouse model of maternal transmission of asthma susceptibility

Epidemiologic data suggest a link between nursing by asthmatic mothers and increased risk of allergy in babies. We sought to experimentally test the potential contribution of breast milk mediator(s) in a mouse model of maternal transmission of asthma risk by evaluating the effect of adoptive nursing on asthma susceptibility in the offspring. We measured airway hyperresponsiveness (AHR) and allergic airway inflammation (AI) after an intentionally suboptimal OVA Ag sensitization, tested the allergen independence of the maternal effect by using a second allergen, casein, for sensitization of the baby mice, and tested the potential role of cytokines by measuring their levels in breast milk. Offspring of asthmatic, but not normal, mothers showed AHR and AI, indicating a maternal transfer of asthma risk. After adoptive nursing, both groups (litters born to asthmatic mothers and nursed by normal mothers, and normal babies nursed by asthmatic mothers) showed AHR (enhanced pause after methacholine aerosol, 50 mg/ml, 3.7 +/- 0.7, 4.2 +/- 0.5, respectively, vs 1.1 +/- 0.1 normal controls, n = 25, p < 0.01) and AI, seen as eosinophilia on histology and bronchoalveolar lavage (40.7 +/- 4.5%, 28.7 +/- 3.7%, vs 1.0 +/- 0.5% normals, n = 25, p < 0.01) after OVA sensitization. Similar results using casein allergen were observed. Multiplex assays for cytokines (IFN-gamma, IL-2, IL-4, IL-5, TNF-alpha, and IL-13) in breast milk were negative. Breast milk is sufficient, but not necessary, to mediate allergen-independent maternal transmission of asthma risk to offspring.

Fish oil supplementation of lactating mothers affects cytokine production in 2 1/2-year-old children

n-3 PUFA influence immune functioning and may affect the cytokine phenotype during development. To examine whether maternal fish oil supplementation during lactation could modify later immune responses in children, 122 lactating Danish mothers with a fish intake below the population median were randomized to groups supplemented for the first 4 mon of lactation with 4.5 g/d of fish oil (equivalent to 1.5 g/d of n-3 long-chain PUFA) or olive oil. Fifty-three mothers with a fish intake in the highest quartile of the population were also included. The FA composition of erythrocyte membranes was measured at 4 mon and at 2 1/2 yr. Plasma immunoglobulin E (IgE) levels and cytokine production in lipopolysaccharide-stimulated whole-blood cultures were determined at 2 1/2 yr. Erythrocyte n-3 PUFA at 4 mon were higher in infants from the fish oil group compared with the olive oil group (P < 0.001) but were no longer different at 2 1/2 yr. The median production of lipopolysaccharide-induced interferon gamma (IFN-gamma) in the fish oil group was fourfold higher than that in the olive oil group (P = 0.034), whereas interleukin-10 (IL-10) production was similar. The IFN-gamma/IL-10 ratio was twofold higher in the fish oil group (P = 0.019) and was positively correlated with 20:5n-3/20:4n-6 in erythrocytes at 4 mon (P = 0.050). The percentages of atopic children and plasma IgE were not different in the two groups, but the study was not designed to look at atopy. Cytokine responses and erythrocyte FA composition in children of mothers with a high fish intake were intermediate in comparison with those in the randomized groups. Fish oil supplementation during lactation resulted in increased in vitro IFN-gamma production in the children 2 yr after the supplementation was given, which may reflect a faster maturation of the immune system.

Breast milk fatty acid composition is associated with development of atopic dermatitis in the infant

OBJECTIVE

Breast milk fatty acids may have immunomodulatory properties related to the development of atopic disease. The aim of this study was to assess the impact of the breast milk fatty acid composition on the development of atopic dermatitis (AD) in high-risk infants.

METHODS

Mothers with atopic disease were recruited at the end of gestation. Maternal food records and breast milk samples were collected at the infants' age of one month. Infants were clinically examined and AD diagnosed at one, three, six, and 12 months.

RESULTS

Altogether 13 of 34 (38%) infants were diagnosed with AD during the first year of life. Infants developing AD had consumed breast milk with a higher ratio of saturated to polyunsaturated fatty acids and less n-3 fatty acids compared to infants not developing AD. Specifically, breast milk consumed by infants with AD contained more stearic acid, 8.9% of total fatty acids (95% confidence interval 7.9-10.0) in comparison to those without AD, 7.1% (95% CI 6.6-7.7).

CONCLUSION

Breast milk rich in saturated and low in n-3 fatty acids may be a risk factor for atopic dermatitis in the infant.

Does fish oil supplementation in pregnancy reduce the risk of allergic disease in infants?

PURPOSE OF REVIEW

Parallel increases in many inflammatory diseases over the last 40 years suggest that common environmental changes are promoting inflammatory immune responses and/or inhibiting the processes that normally keep these in check. One key change during this period has been declining intakes of anti-inflammatory dietary factors, including omega-3 polyunsaturated fatty acids (n-3 PUFA). As allergic diseases often first manifest in early infancy, prevention strategies need to be targeted early, even in utero. This review will examine recent evidence for the use of fish oil during this early period as a primary prevention strategy for allergic disease.

RECENT FINDINGS

N-3 PUFA have well documented anti-inflammatory effects in vitro and have also been demonstrated to have health benefits in a range of chronic inflammatory diseases, including cardiovascular disease, rheumatoid arthritis and diabetes, supporting their role in modulating inflammation in vivo. Although the effects of fish oil supplementation in established allergic disease are less convincing, there is accumulating evidence that dietary n-3 PUFA may have greater effects before allergic responses are established.

SUMMARY

Supplementation of the maternal diet in pregnancy with n-3 PUFA may provide a non-invasive intervention with significant potential to prevent the development of allergic and possibly other immune-mediated diseases.