Supplementation of Mice with Specific Nondigestible Oligosaccharides during Pregnancy or Lactation Leads to Diminished Sensitization and Allergy in the Female Offspring

Human Breast Milk: The Role of Its Microbiota and Metabolites in Infant Health

This review explores the role of microorganisms and metabolites in human breast milk and their impact on neonatal health. Breast milk serves as both a primary source of nutrition for newborns and contributes to the development and maturation of the digestive, immunological, and neurological systems. It has the potential to reduce the risks of infections, allergies, and asthma. As our understanding of the properties of human milk advances, there is growing interest in incorporating its benefits into personalized infant nutrition strategies, particularly in situations in which breastfeeding is not an option. Future infant formula products are expected to emulate the composition and advantages of human milk, aligning with an evolving understanding of infant nutrition. The long-term health implications of human milk are still under investigation.

Complex interplay of gut microbiota between obesity and asthma in children

Obesity is an important risk factor and common comorbidity of childhood asthma. Simultaneously, obesity-related asthma, a distinct asthma phenotype, has attracted significant attention owing to its association with more severe clinical manifestations, poorer disease control, and reduced quality of life. The establishment of the gut microbiota during early life is essential for maintaining metabolic balance and fostering the development of the immune system in children. Microbial dysbiosis influences host lipid metabolism, triggers chronic low-grade inflammation, and affects immune responses. It is intimately linked to the susceptibility to childhood obesity and asthma and plays a potentially crucial transitional role in the progression of obesity-related asthma. This review article summarizes the latest research on the interplay between asthma and obesity, with a particular focus on the mediating role of gut microbiota in the pathogenesis of obesity-related asthma. This study aims to provide valuable insight to enhance our understanding of this condition and offer preliminary evidence to support the development of therapeutic interventions.

Plant-Based Dietary Fibers and Polysaccharides as Modulators of Gut Microbiota in Intestinal and Lung Inflammation: Current State and Challenges

Recent research has underscored the significant role of gut microbiota in managing various diseases, including intestinal and lung inflammation. It is now well established that diet plays a crucial role in shaping the composition of the microbiota, leading to changes in metabolite production. Consequently, dietary interventions have emerged as promising preventive and therapeutic approaches for managing these diseases. Plant-based dietary fibers, particularly polysaccharides and oligosaccharides, have attracted attention as potential therapeutic agents for modulating gut microbiota and alleviating intestinal and lung inflammation. This comprehensive review aims to provide an in-depth overview of the current state of research in this field, emphasizing the challenges and limitations associated with the use of plant-based dietary fibers and polysaccharides in managing intestinal and lung inflammation. By shedding light on existing issues and limitations, this review seeks to stimulate further research and development in this promising area of therapeutic intervention.

Maternal prebiotic supplementation impacts colitis development in offspring mice

Background and aims

Maternal diet plays a key role in preventing or contributing to the development of chronic diseases, such as obesity, allergy, and brain disorders. Supplementation of maternal diet with prebiotics has been shown to reduce the risk of food allergies and affect the intestinal permeability in offspring later in life. However, its role in modulating the development of other intestinal disorders, such as colitis, remains unknown. Therefore, we investigated the effects of prebiotic supplementation in pregnant mice on the occurrence of colitis in their offspring.

Materials and methods

Offspring from mothers, who were administered prebiotic galacto-oligosaccharides and inulin during gestation or fed a control diet, were subjected to three cycles of dextran sulphate sodium (DSS) treatment to induce chronic colitis, and their intestinal function and disease activity were evaluated. Colonic remodelling, gut microbiota composition, and lipidomic and transcriptomic profiles were also assessed.

Results

DSS-treated offspring from prebiotic-fed mothers presented a higher disease score, increased weight loss, and increased faecal humidity than those from standard diet-fed mothers. DSS-treated offspring from prebiotic-fed mothers also showed increased number of colonic mucosal lymphocytes and macrophages than the control group, associated with the increased colonic concentrations of resolvin D5, protectin DX, and 14-hydroxydocosahexaenoic acid, and modulation of colonic gene expression. In addition, maternal prebiotic supplementation induced an overabundance of eight bacterial families and a decrease in the butyrate caecal concentration in DSS-treated offspring.

Conclusion

Maternal prebiotic exposure modified the microbiota composition and function, lipid content, and transcriptome of the colon of the offspring. These modifications did not protect against colitis, but rather sensitised the mice to colitis development.

Study Protocol for a Randomised Controlled Trial Investigating the Effects of Maternal Prebiotic Fibre Dietary Supplementation from Mid-Pregnancy to Six Months’ Post-Partum on Child Allergic Disease Outcomes

Infant allergy is the most common early manifestation of an increasing propensity for inflammation and immune dysregulation in modern environments. Refined low-fibre diets are a major risk for inflammatory diseases through adverse effects on the composition and function of gut microbiota. This has focused attention on the potential of prebiotic dietary fibres to favourably change gut microbiota, for local and systemic anti-inflammatory effects. In pregnancy, the immunomodulatory effects of prebiotics may also have benefits for the developing fetal immune system, and provide a potential dietary strategy to reduce the risk of allergic disease. Here, we present the study protocol for a double-blinded, randomised controlled trial investigating the effects of maternal prebiotics supplementation on child allergic disease outcomes. Eligible pregnant women have infants with a first-degree relative with a history of medically diagnosed allergic disease. Consented women are randomised to consume either prebiotics (galacto-oligosaccharides and fructo-oligosaccharides) or placebo (maltodextrin) powder daily from 18–20 weeks’ gestation to six months’ post-partum. The target sample size is 652 women. The primary outcome is infant medically diagnosed eczema; secondary outcomes include allergen sensitisation, food allergies and recurrent wheeze. Breast milk, stool and blood samples are collected at multiple timepoints for further analysis.

Targeted allergen-specific immunotherapy within the skin improves allergen delivery to induce desensitization to peanut

Aim: Epicutaneous immunotherapy (EPIT) with peanut has been demonstrated to be safe but efficacy may be limited by allergen uptake through the skin barrier. To enhance allergen uptake into the skin, the authors used peanut-coated microneedles and compared them with EPIT in a peanut allergy mouse model. Methods: Sensitized mice were treated with peanut-coated microneedles or peanut-EPIT and then challenged with peanut to determine protection. Results: Treatment with peanut-coated microneedles was safe and showed enhanced desensitization to peanut compared with peanut-EPIT administered via a similar schedule. Protection was associated with reduced Th2 immune responses and mast cell accumulation in the intestine. Conclusion: Peanut-coated microneedles have the potential to present a safe method of improving allergen delivery for cutaneous immunotherapy.

Prebiotic Supplementation During Gestation Induces a Tolerogenic Environment and a Protective Microbiota in Offspring Mitigating Food Allergy

Food allergy is associated with alterations in the gut microbiota, epithelial barrier, and immune tolerance. These dysfunctions are observed within the first months of life, indicating that early intervention is crucial for disease prevention. Preventive nutritional strategies with prebiotics are an attractive option, as prebiotics such as galacto-oligosaccharides and inulin can promote tolerance, epithelial barrier reinforcement, and gut microbiota modulation. Nonetheless, the ideal period for intervention remains unknown. Here, we investigated whether galacto-oligosaccharide/inulin supplementation during gestation could protect offspring from wheat allergy development in BALB/cJRj mice. We demonstrated that gestational prebiotic supplementation promoted the presence of beneficial strains in the fecal microbiota of dams during gestation and partially during mid-lactation. This specific microbiota was transferred to their offspring and maintained to adulthood. The presence of B and T regulatory immune cell subsets was also increased in the lymph nodes of offspring born from supplemented mothers, suggestive of a more tolerogenic immune environment. Indeed, antenatal prebiotic supplementation reduced the development of wheat allergy symptoms in offspring. Our study thus demonstrates that prebiotic supplementation during pregnancy induces, in the offspring, a tolerogenic environment and a microbial imprint that mitigates food allergy development.

Exposure to Deoxynivalenol During Pregnancy and Lactation Enhances Food Allergy and Reduces Vaccine Responsiveness in the Offspring in a Mouse Model

Deoxynivalenol (DON), a highly prevalent contaminant of grain-based products, is known to induce reproductive- and immunotoxicities. Considering the importance of immune development in early life, the present study investigated the effects of perinatal DON exposure on allergy development and vaccine responsiveness in the offspring. Pregnant mice received control or DON-contaminated diets (12.5 mg/kg diet) during pregnancy and lactation. After weaning, female offspring were sensitized to ovalbumin (OVA) by oral administration of OVA with cholera toxin (CT). Male offspring were injected with Influvac vaccine. OVA-specific acute allergic skin response (ASR) in females and vaccine-specific delayed-type hypersensitivity (DTH) in males were measured upon intradermal antigen challenge. Immune cell populations in spleen and antigen-specific plasma immunoglobulins were analyzed. In female CT+OVA-sensitized offspring of DON-exposed mothers ASR and OVA-specific plasma immunoglobulins were significantly higher, compared to the female offspring of control mothers. In vaccinated male offspring of DON-exposed mothers DTH and vaccine-specific antibody levels were significantly lower, compared to the male offspring of control mothers. In both models a significant reduction in regulatory T cells, Tbet+ Th1 cells and Th1-related cytokine production of the offspring of DON-exposed mothers was observed. In conclusion, early life dietary exposure to DON can adversely influence immune development in the offspring. Consequently, the immune system of the offspring may be skewed towards an imbalanced state, resulting in an increased allergic immune response to food allergens and a decreased immune response to vaccination against influenza virus in these models.

Microbiota Changes in Fathers Consuming a High Prebiotic Fiber Diet Have Minimal Effects on Male and Female Offspring in Rats

BACKGROUND

Consuming a diet high in prebiotic fiber has been associated with improved metabolic and gut microbial parameters intergenerationally, although studies have been limited to maternal intake with no studies examining this effect in a paternal model.

METHOD

Male Sprague Dawley rats were allocated to either (1) control or (2) oligofructose-supplemented diet for nine weeks and then mated. Offspring consumed control diet until 16 weeks of age. Bodyweight, body composition, glycemia, hepatic triglycerides, gastrointestinal hormones, and gut microbiota composition were measured in fathers and offspring.

RESULTS

Paternal energy intake was reduced, while satiety inducing peptide tyrosine tyrosine (PYY) gut hormone was increased in prebiotic versus control fathers. Increased serum PYY persisted in female prebiotic adult offspring. Hepatic triglycerides were decreased in prebiotic fathers with a similar trend (p = 0.07) seen in female offspring. Gut microbial composition showed significantly reduced alpha diversity in prebiotic fathers at 9 and 12 weeks of age (p < 0.001), as well as concurrent differences in beta diversity (p < 0.001), characterized by differences in Bifidobacteriaceae, Lactobacillaceae and Erysipelotrichaceae, and particularly Bifidobacterium animalis. Female prebiotic offspring had higher alpha diversity at 3 and 9 weeks of age (p < 0.002) and differences in beta diversity at 15 weeks of age (p = 0.04). Increases in Bacteroidetes in female offspring and Christensenellaceae in male offspring were seen at nine weeks of age.

CONCLUSIONS

Although paternal prebiotic intake before conception improves metabolic and microbiota outcomes in fathers, effects on offspring were limited with increased serum satiety hormone levels and changes to only select gut bacteria.

Perinatal and Early-Life Nutrition, Epigenetics, and Allergy

Epidemiological studies have shown a dramatic increase in the incidence and the prevalence of allergic diseases over the last several decades. Environmental triggers including risk factors (e.g., pollution), the loss of rural living conditions (e.g., farming conditions), and nutritional status (e.g., maternal, breastfeeding) are considered major contributors to this increase. The influences of these environmental factors are thought to be mediated by epigenetic mechanisms which are heritable, reversible, and biologically relevant biochemical modifications of the chromatin carrying the genetic information without changing the nucleotide sequence of the genome. An important feature characterizing epigenetically-mediated processes is the existence of a time frame where the induced effects are the strongest and therefore most crucial. This period between conception, pregnancy, and the first years of life (e.g., first 1000 days) is considered the optimal time for environmental factors, such as nutrition, to exert their beneficial epigenetic effects. In the current review, we discussed the impact of the exposure to bacteria, viruses, parasites, fungal components, microbiome metabolites, and specific nutritional components (e.g., polyunsaturated fatty acids (PUFA), vitamins, plant- and animal-derived microRNAs, breast milk) on the epigenetic patterns related to allergic manifestations. We gave insight into the epigenetic signature of bioactive milk components and the effects of specific nutrition on neonatal T cell development. Several lines of evidence suggest that atypical metabolic reprogramming induced by extrinsic factors such as allergens, viruses, pollutants, diet, or microbiome might drive cellular metabolic dysfunctions and defective immune responses in allergic disease. Therefore, we described the current knowledge on the relationship between immunometabolism and allergy mediated by epigenetic mechanisms. The knowledge as presented will give insight into epigenetic changes and the potential of maternal and post-natal nutrition on the development of allergic disease.

The Impact of Milk and Its Components on Epigenetic Programming of Immune Function in Early Life and Beyond: Implications for Allergy and Asthma

Specific and adequate nutrition during pregnancy and early life is an important factor in avoiding non-communicable diseases such as obesity, type 2 diabetes, cardiovascular disease, cancers, and chronic allergic diseases. Although epidemiologic and experimental studies have shown that nutrition is important at all stages of life, it is especially important in prenatal and the first few years of life. During the last decade, there has been a growing interest in the potential role of epigenetic mechanisms in the increasing health problems associated with allergic disease. Epigenetics involves several mechanisms including DNA methylation, histone modifications, and microRNAs which can modify the expression of genes. In this study, we focus on the effects of maternal nutrition during pregnancy, the effects of the bioactive components in human and bovine milk, and the environmental factors that can affect early life (i.e., farming, milk processing, and bacterial exposure), and which contribute to the epigenetic mechanisms underlying the persistent programming of immune functions and allergic diseases. This knowledge will help to improve approaches to nutrition in early life and help prevent allergies in the future.

Human Milk From Atopic Mothers Has Lower Levels of Short Chain Fatty Acids

Short chain fatty acids (SFCAs) are microbial metabolites produced in the gut upon fermentation of dietary fiber. These metabolites interact with the host immune system and can elicit epigenetic effects. There is evidence to suggest that SCFAs may play a role in the developmental programming of immune disorders and obesity, though evidence in humans remains sparse. Here we have quantified human milk (HM) SCFA levels in an international cohort of atopic and non-atopic mothers (n = 109). Our results demonstrate that human milk contains detectable levels of the SCFAs acetate, butyrate, and formate. Samples from atopic mothers had significantly lower concentrations of acetate and butyrate than those of non-atopic mothers. HM SCFA levels in atopic and non-atopic women also varied based on maternal country of residence (Australia, Japan, Norway, South Africa, USA). Reduced exposure to HM SCFA in early life may program atopy or overweight risk in breastfed infants.

The inhibitory activity of alginate against allergic reactions in an ovalbumin-induced mouse model

Marine seaweed polysaccharides have been considered as a potential resource for antiallergic therapy. Alginate is an acidic linear polysaccharide and soluble dietary fiber that was extracted from brown algae, Laminaria japonica. The molecular weight of alginate was 108 kDa, and its water solution exhibited non-Newtonian characteristics, including viscoelasticity and shear-thinning behavior. The ability of alginate to inhibit allergic reactions was investigated in ovalbumin (OVA)-induced BALB/c mice, which have been widely used as a mouse model of egg allergy. The results showed that alginate could effectively attenuate the occurrence of allergic reactions, including improving the integrity of the intestinal epithelial villi and inhibition of mast cell degranulation in the jejunum, in OVA-induced mice. Moreover, after treatment with alginate, the levels of IgE, histamine and IL-4 in OVA-induced mice were remarkably decreased, and the levels of IFN-γ were markedly increased. In addition, the number of Treg cells in spleen tissues in OVA-induced mice was increased by alginate, and the OVA-induced differentiation of Th0 cells into Th2 cells was significantly inhibited. These results demonstrate that alginate possesses potential antiallergic activities in a mouse model of egg allergy, which might provide important evidence that alginate, extracted from Laminaria japonica, can be developed into a novel functional food for inhibiting egg allergy.

Overview of in vivo and ex vivo endpoints in murine food allergy models: Suitable for evaluation of the sensitizing capacity of novel proteins?

Significant efforts are necessary to introduce new dietary protein sources to feed a growing world population while maintaining food supply chain sustainability. Such a sustainable protein transition includes the use of highly modified proteins from side streams or the introduction of new protein sources that may lead to increased clinically relevant allergic sensitization. With food allergy being a major health problem of increasing concern, understanding the potential allergenicity of new or modified proteins is crucial to ensure public health protection. The best predictive risk assessment methods currently relied on are in vivo models, making the choice of endpoint parameters a key element in evaluating the sensitizing capacity of novel proteins. Here, we provide a comprehensive overview of the most frequently used in vivo and ex vivo endpoints in murine food allergy models, addressing their strengths and limitations for assessing sensitization risks. For optimal laboratory‐to‐laboratory reproducibility and reliable use of predictive tests for protein risk assessment, it is important that researchers maintain and apply the same relevant parameters and procedures. Thus, there is an urgent need for a consensus on key food allergy parameters to be applied in future food allergy research in synergy between both knowledge institutes and clinicians.

Impact of maternal dietary gut microbial metabolites on an offspring's systemic immune response in mouse models

The gut microbiota has a great impact on the host immune systems. Recent evidence suggests that the maternal gut microbiota affects the immune systems of offspring. Metabolites produced by the gut microbiota play crucial roles in the immune system. Previous studies have also revealed that metabolites such as short-chain fatty acids (SCFAs) and the aryl hydrocarbon receptor (AhR) ligands are involved in host health and diseases. Great progress has been made in understanding the roles of diet-derived SCFAs in the offspring’s immune system. The findings to date raise the possibility that maternal dietary soluble fiber intake may play a role in the development of the offspring’s systemic immune response. In this review, we summarize the present knowledge and discuss future therapeutic possibilities for using dietary soluble fiber intake against inflammatory diseases.

Prebiotics: Mechanisms and Preventive Effects in Allergy

Allergic diseases now affect over 30% of individuals in many communities, particularly young children, underscoring the need for effective prevention strategies in early life. These allergic conditions have been linked to environmental and lifestyle changes driving the dysfunction of three interdependent biological systems: microbiota, epithelial barrier and immune system. While this is multifactorial, dietary changes are of particular interest in the altered establishment and maturation of the microbiome, including the associated profile of metabolites that modulate immune development and barrier function. Prebiotics are non-digestible food ingredients that beneficially influence the health of the host by 1) acting as a fermentable substrate for some specific commensal host bacteria leading to the release of short-chain fatty acids in the gut intestinal tract influencing many molecular and cellular processes; 2) acting directly on several compartments and specifically on different patterns of cells (epithelial and immune cells). Nutrients with prebiotic properties are therefore of central interest in allergy prevention for their potential to promote a more tolerogenic environment through these multiple pathways. Both observational studies and experimental models lend further credence to this hypothesis. In this review, we describe both the mechanisms and the therapeutic evidence from preclinical and clinical studies exploring the role of prebiotics in allergy prevention.

Regulatory Roles of Pectin Oligosaccharides on Immunoglobulin Production in Healthy Mice Mediated by Gut Microbiota

SCOPE

The prebiotic regulation of the gut microbiota is a promising strategy to induce protective humoral and mucosal immune responses. The potential immune-improving effects of pectin oligosaccharides (POS) in healthy mice and the potential mechanism mediated by specific intestinal bacteria are investigated.

METHODS AND RESULTS

POS is prepared using a hydrogen-peroxide-assisted degradation. Mice that consumed diets containing POS are tested for microbial community shifts, short-chain fatty acids (SCFAs), and immunoglobulin (Ig) production using quantitative real-time polymerase chain reaction, gas chromatography, and ELISA kits. Pearson's correlation analyses are performed between Ig production and specific intestinal bacteria or SCFAs. POS treatment significantly improves the growth of healthy mice. Moreover, 4-week POS administration results in a profound change in intestinal microbial composition and a significantly higher fecal concentration of acetate, which leads to substantial increases of the levels of fecal secretory immunoglobulin A and serum IgG.

CONCLUSIONS

The results suggest that the inclusion of POS in a diet can increase Ig production and optimize the composition of the gut microbiota. A significant correlation is observed between changes in Ig production and specific intestinal bacteria or acetate, providing insight into the mechanism of POS as a potential immune-enhancing supplement.

Polyphenol Effects on Splenic Cytokine Response in Post-Weaning Contactin 1-Overexpressing Transgenic Mice

Background: In mice, postnatal immune development has previously been investigated, and evidence of a delayed maturation of the adaptive immune response has been detected. Methods: In this study, the effects of red grape polyphenol oral administration on the murine immune response were explored using pregnant mice (TAG/F3 transgenic and wild type (wt) mice) as the animal model. The study was performed during pregnancy as well as during lactation until postnatal day 8. Suckling pups from polyphenol-administered dams as well as day 30 post-weaning pups (dietary-administered with polyphenols) were used. Polyphenol effects were evaluated, measuring splenic cytokine secretion. Results: Phorbol myristate acetate-activated splenocytes underwent the highest cytokine production at day 30 in both wt and TAG/F3 mice. In the latter, release of interferon (IFN)-γ and tumor necrosis factor (TNF)-α was found to be higher than in the wt counterpart. In this context, polyphenols exerted modulating activities on day 30 TAG/F3 mice, inducing release of interleukin (IL)-10 in hetero mice while abrogating release of IL-2, IFN-γ, TNF-α, IL-6, and IL-4 in homo and hetero mice. Conclusion: Polyphenols are able to prevent the development of an inflammatory/allergic profile in postnatal TAG/F3 mice.

AllergoOncology: Microbiota in allergy and cancer-A European Academy for Allergy and Clinical Immunology position paper

The microbiota can play important roles in the development of human immunity and the establishment of immune homeostasis. Lifestyle factors including diet, hygiene, and exposure to viruses or bacteria, and medical interventions with antibiotics or anti-ulcer medications, regulate phylogenetic variability and the quality of cross talk between innate and adaptive immune cells via mucosal and skin epithelia. More recently, microbiota and their composition have been linked to protective effects for health. Imbalance, however, has been linked to immune-related diseases such as allergy and cancer, characterized by impaired, or exaggerated immune tolerance, respectively. In this AllergoOncology position paper, we focus on the increasing evidence defining the microbiota composition as a key determinant of immunity and immune tolerance, linked to the risk for the development of allergic and malignant diseases. We discuss novel insights into the role of microbiota in disease and patient responses to treatments in cancer and in allergy. These may highlight opportunities to improve patient outcomes with medical interventions supported through a restored microbiome.

Maternal L-proline supplementation during gestation alters amino acid and polyamine metabolism in the first generation female offspring of C57BL/6J mice

We recently reported that dietary supplementation with L-proline (proline) during gestation improved embryonic survival in C57BL/6J mice. The objective of the present study was to test the hypothesis that the effect of maternal proline supplementation on embryonic survival can be carried forward to the first generation female offspring. In the F0 generation, pregnant dams were fed a purified diet supplemented with 0 (control) or 5 g proline/kg diet. The F1 female adult offsprings were bred to fertile males. Fetal survival at embryonic day (E)12.5 and reproductive outcomes at term birth were recorded. The concentrations of amino acids, ammonia, and urea in plasma and amniotic fluid, as well as concentrations of polyamines in placental tissues and amniotic fluid at E12.5 were determined. Results showed that the F1 generation female offspring from proline-supplemented dams had higher (P < 0.05) concentrations of glutamate and taurine in plasma; of putrescine and spermidine in placental tissues; and of glycine, taurine, and spermidine in amniotic fluid at E12.5, as compared with F1 generation female offsprings from dams without proline supplementation. Concentration of proline in the plasma of offspring mice from proline-supplemented dams were lower (P < 0.05), as compared with the control group. No differences in fetal survival, reproductive outcomes, or concentrations of ammonia and urea in plasma and amniotic fluid were observed between the two groups of F1 female offspring. Collectively, our results indicate that the benefits of maternal proline supplementation during gestation on improving embryonic survival and fetal growth in F0 females are not transmitted to their F1 generation females.

Strategies to reduce non-communicable diseases in the offspring: negative and positive in utero programming

Non-communicable diseases (NCDs) are a major problem as they are the leading cause of death and represent a substantial economic cost. The 'Developmental Origins of Health and Disease Hypothesis' proposes that adverse stimuli at different life stages can increase the predisposition to these diseases. In fact, adverse in utero programming is a major origin of these diseases due to the high malleability of embryonic development. This review provides a comprehensive analysis of the scientific literature on in utero programming and NCDs highlighting potential medical strategies to prevent these diseases based upon this programming. We fully address the concept and mechanisms involved in this programming (anatomical disruptions, epigenetic modifications and microbiota alterations). We also examine the negative role of in utero programming on the increased predisposition of NCDs in the offspring, which introduces the passive medical approach that consists of avoiding adverse stimuli including an unhealthy diet and environmental chemicals. Finally, we extensively discuss active medical approaches that target the causes of NCDs and have the potential to significantly and rapidly reduce the incidence of NCDs. These approaches can be classified as direct in utero programming modifications and personalized lifestyle pregnancy programs; they could potentially provide transgenerational NCDs protection. Active strategies against NCDs constitute a promising tool for the reduction in NCDs.

Effect of Dietary Fiber and Metabolites on Mast Cell Activation and Mast Cell-Associated Diseases

Many mast cell-associated diseases, including allergies and asthma, have seen a strong increase in prevalence during the past decades, especially in Western(ized) countries. It has been suggested that a Western diet may contribute to the prevalence and manifestation of allergies and asthma through reduced intake of dietary fiber and the subsequent production of their metabolites. Indeed, dietary fiber and its metabolites have been shown to positively influence the development of immune disorders via changes in microbiota composition and the regulation of B- and T-cell activation. However, the effects of these dietary components on the activation of mast cells, key effector cells of the inflammatory response in allergies and asthma, remain poorly characterized. Due to their location in the gut and vascularized tissues, mast cells are exposed to high concentrations of dietary fiber and/or its metabolites. Here, we provide a focused overview of current findings regarding the direct effects of dietary fiber and its various metabolites on the regulation of mast cell activity and the pathophysiology of mast cell-associated diseases.

Human Milk Oligosaccharides Attenuate Antigen-Antibody Complex Induced Chemokine Release from Human Intestinal Epithelial Cell Lines

There has been increased interest in the use of dietary ingredients, including prebiotics such as human-milk oligosaccharides (HMOs), as therapeutic strategies for food allergy. Understanding the mechanisms underlying the beneficial effects of HMOs is important to realizing their therapeutic potential. Here we demonstrate that the HMO, 6'-sialyllactose (6'SL) inhibited chemokine (IL-8 and CCL20) release from T-84 and HT-29 cells stimulated with antigen-antibody complex, TNFα or PGE₂ ; an effect that was PPARγ dependent and associated with decreased activity of the transcription factors AP-1 and NFκB. In contrast, 2'-fucosyllactose (2'FL) selectively inhibited CCL20 release in response to antigen antibody complex in a PPARγ independent manner. This study reinforces the concept that structurally different oligosaccharides have distinct biological activities and identifies, for the first time, that the HMOs, 6'SL, and 2'FL, modulate human epithelial cell responses related to allergic disease. These findings encourage further investigation of the therapeutic potential of specific HMOs in food allergy.

PRACTICAL APPLICATION

This study provides evidence for direct effects of HMOs in addition to their prebiotic role and demonstrates, for the first time, modulation of Ag-IgE complex activation of human epithelial cells that may have important implications for food-allergy. The study also reinforces the concept that structurally different oligosaccharides have distinct biological activities. In determining the composition of infant formula, addition of oligosaccharides with specific structures may provide direct modulation of immune responses and potentially attenuate symptoms or development of food allergy.

The maternal microbiome during pregnancy and allergic disease in the offspring

There is substantial epidemiological and mechanistic evidence that the increase in allergic disease and asthma in many parts of the world in part relates to changes in microbial exposures and diet acting via the composition and metabolic products of the intestinal microbiome. The majority of research in this field has focused on the gut microbiome during infancy, but it is increasingly clear that the maternal microbiome during pregnancy also has a key role in preventing an allergy-prone immune phenotype in the offspring. The mechanisms by which the maternal microbiome influences the developing fetal immune system include alignment between the maternal and infant regulatory immune status and transplacental passage of microbial metabolites and IgG. Interplay between microbial stimulatory factors such as lipopolysaccharides and regulatory factors such as short-chain fatty acids may also influence on fetal immune development. However, our understanding of these pathways is at an early stage and further mechanistic studies are needed. There are also no data from human studies relating the composition and metabolic activity of the maternal microbiome during pregnancy to the offspring's immune status at birth and risk of allergic disease. Improved knowledge of these pathways may inform novel strategies for tackling the increase in allergic disorders in the modern world.

Prenatal and postnatal administration of prebiotics and probiotics

Colonization of the neonatal gut by beneficial bacteria is important for the establishment and maintenance of the mucosal barrier, thus protecting the neonate from enteric pathogens and local and systemic inflammation. The neonatal microbiome is influenced by infant diet, environment, and the maternal microbiome. Dysbiosis in pregnancy increases the risk of pre-eclampsia, diabetes, infection, preterm labor, and later childhood atopy. Dysbiosis of the neonatal gut plays an important role in colic in the term infant, in the disease processes which plague preterm infants, including necrotizing enterocolitis and sepsis, and in the long-term outcomes of neonates. Administration of enteral prebiotics, probiotics, and synbiotics during pregnancy, lactation, and postnatal life appears to be a safe and feasible method to alter the maternal and neonatal microbiome, thus improving pregnancy and neonatal outcomes.

Re-evaluation of pectin (E 440i) and amidated pectin (E 440ii) as food additives

Following a request from the European Commission, the EFSA Panel on Food Additives and Nutrient sources added to Food (ANS) was asked to deliver a scientific opinion on the re-evaluation of pectin (E 440i) and amidated pectin (E 440ii) as food additives. An acceptable daily intake (ADI) 'not specified' was allocated by the Scientific Committee for Food (SCF) for E 440i and E 440ii. Pectin and amidated pectin would not be absorbed intact, but extensively fermented by intestinal microbiota in animals and humans; products formed from pectins in the gastrointestinal tract are similar to manufactured pectin-derived acidic oligosaccharides (pAOS). There is no indication of genotoxicity for pectin and amidated pectin, although the available data were limited. No adverse effects were reported in a chronic toxicity study in rats at levels up to 5,000 mg pectin/kg bw per day, the highest dose tested. No treatment-related effects were observed in a dietary one-generation reproductive toxicity study with pAOS in rats at up to 6,200 mg/kg body weight (bw) per day, the highest dose tested. The Panel did not consider E 440i and E 440ii as having allergenic potential. A dose of 36 g/day (equivalent to 515 mg/kg bw per day) for 6 weeks in humans was without adverse effects. Exposure to pectins from their use as food additives ranged up to 442 mg/kg bw per day for toddlers at the 95th percentile (brand-loyal scenario). The Panel concluded that there is no safety concern for the use of pectin (E 440i) and amidated pectin (E 440ii) as food additives for the general population and that there is no need for a numerical ADI.

An unusual cause of food-induced anaphylaxis in mothers

BACKGROUND

Galacto-oligosaccharides (GOS) are prebiotics added to commercial milk formula of infants and mothers. In recent years, cases of allergy related to GOS in atopic children have been reported in the South East Asian region.

CASE PRESENTATIONS

We describe a series of pregnant (n = 4) and lactating mothers (n = 2) who developed anaphylactic reactions after consumption of maternal milk formula containing GOS. All six subjects had pre-existing atopy and a positive skin prick test to GOS and 5/5 of the subjects who were tested had positive basophil activation tests to GOS. All of the mothers and their babies had normal neonatal outcomes after the reactions.

CONCLUSIONS

The supplementation of GOS into milk and beverages in the Asian region should take into account the rare chance of allergenicity of GOS in the atopic population.

Maternal short-chain fructo-oligosaccharide supplementation increases intestinal cytokine secretion, goblet cell number, butyrate concentration and Lawsonia intracellularis humoral vaccine response in weaned pigs

Prebiotic supplementation modulates immune system development and function. However, less is known about the effects of maternal prebiotic consumption on offspring intestinal defences and immune system responsiveness. We investigated the effects of maternal short-chain fructo-oligosaccharide (scFOS) supplementation on mucin-secreting cells, ileal secretory IgA and cytokine secretion of weaned offspring and their humoral response to an oral vaccine against obligate intracellular Lawsonia intracellularis. Sows were fed a control diet (CTRL) or scFOS-supplemented diet during the last third of gestation and throughout lactation. At weaning, each litter was divided into two groups receiving a post-weaning CTRL or scFOS diet for a month. Pigs from the four groups were either non-vaccinated (n 16) or vaccinated (n 117) at day 33. Biomarkers related to intestinal defences and immune parameters were analysed 3 weeks later. SCFA production was assessed over time in suckling and weaned pigs. Maternal scFOS supplementation improved ileal cytokine secretions (interferon (IFN)-γ, P<0·05; IL-4, P=0·07) and tended to increase caecal goblet cell number (P=0·06). It increased IgA vaccine response in the serum (P<0·01) and ileal mucosa (P=0·08). Higher bacterial fermentative activity was observed during lactation (total faecal SCFA, P<0·001) and after weaning (colonic butyrate, P=0·10) in pigs from scFOS-supplemented mothers. No synergistic effect between maternal and post-weaning scFOS supplementation was observed. Therefore, maternal scFOS supplementation has long-lasting consequences by strengthening gut defences and immune response to a vaccine against an intestinal obligate intracellular pathogen. Prebiotic consumption by gestating and lactating mothers is decisive in modulating offspring intestinal immunity.

Current challenges facing the assessment of the allergenic capacity of food allergens in animal models

Food allergy is a major health problem of increasing concern. The insufficiency of protein sources for human nutrition in a world with a growing population is also a significant problem. The introduction of new protein sources into the diet, such as newly developed innovative foods or foods produced using new technologies and production processes, insects, algae, duckweed, or agricultural products from third countries, creates the opportunity for development of new food allergies, and this in turn has driven the need to develop test methods capable of characterizing the allergenic potential of novel food proteins. There is no doubt that robust and reliable animal models for the identification and characterization of food allergens would be valuable tools for safety assessment. However, although various animal models have been proposed for this purpose, to date, none have been formally validated as predictive and none are currently suitable to test the allergenic potential of new foods. Here, the design of various animal models are reviewed, including among others considerations of species and strain, diet, route of administration, dose and formulation of the test protein, relevant controls and endpoints measured.

High-Fat and Low-Carbohydrate Diets Are Associated with Allergic Rhinitis But Not Asthma or Atopic Dermatitis in Children

BACKGROUND

Numerous studies have suggested that nutritional intake is related to allergic diseases. Although conflicting results exist, fat intake is often associated with allergic diseases. We investigated the relationship between allergic diseases and nutritional intake after adjusting for various demographic and socioeconomic factors in a large, representative sample of Korean children.

METHODS

A total of 3,040 participants, aged 4 to 13 years old, were enrolled in the present study from the Korean National Health and Nutrition Examination Survey (KNHANES), 2010-2012. Nutritional intake data, including total calories, protein, fat, carbohydrate, vitamin A, vitamin C, thiamine, riboflavin, and niacin, were retrieved from the survey using the complete 24-hour recall method. The associations between each nutritional factor and allergic rhinitis/asthma/atopic dermatitis were analyzed using simple and multiple logistic regression analyses with complex sampling. Age, sex, body mass index (BMI), number of household members, income level, and region of residence were adjusted for as covariates.

RESULTS

Of the participants, 22.1%, 6.0%, and 15.5% suffered from allergic rhinitis, asthma, and atopic dermatitis, respectively. Allergic rhinitis was significantly correlated with high-fat and low-carbohydrate diets. The adjusted odds ratio (AOR) was 1.25 (95% CIs = 1.06-1.46, P = 0.007) for fat intake, denoting a 10% increase. Carbohydrate intake (10% increase) was negatively related to allergic rhinitis with an AOR of 0.84 (95% CIs = 0.74-0.95, P = 0.004). No other significant relationships were found between the retrieved nutritional factors and either asthma or atopic dermatitis.

CONCLUSION

Allergic rhinitis was related to high-fat and low-carbohydrate diets. Although the underlying mechanisms and causal relationships remain elusive, the present study provides reliable evidence regarding the associations between nutritional factors and allergic rhinitis by considering numerous factors within a large and representative population.

Maternal exposure to GOS/inulin mixture prevents food allergies and promotes tolerance in offspring in mice

BACKGROUND

Food allergies affect 4-8% of children and are constantly on the rise, thus making allergies a timely issue. Most importantly, prevention strategies are nonexistent, and current therapeutic strategies have limited efficacy and need to be improved. One alternative to prevent or reduce allergies, particularly during infancy, could consist of modulating maternal immunity and microbiota using nondigestible food ingredients, such as prebiotics. For this purpose, we studied the preventive effects of prebiotics in Balb/c mothers during pregnancy and breastfeeding on food allergy development in offspring mice.

METHODS

After weaning, the offspring from mothers that were exposed to GOS/inulin mixture or fed a control diet were intraperitoneally sensitized to wheat proteins to induce a systemic allergic response and orally exposed to the same allergen. Immunological, physiological, and microbial parameters were analyzed.

RESULTS

GOS/inulin mixture diet modified the microbiota of mothers and their offspring. Offspring from mothers that received GOS/inulin prebiotics were protected against food allergies and displayed lower clinical scores, specifically of IgE and histamine levels, compared to offspring from mothers fed a control diet. Moreover, GOS/inulin supplementation for the mother resulted in stronger intestinal permeability in the offspring. Enhancement of the regulatory response to allergic inflammation and changes in the Th2/Th1 balance toward a dampened Th2 response were observed in mice from GOS/inulin mixture-exposed mothers.

CONCLUSION

The treatment of pregnant and lactating mice with nondigestible GOS/inulin prebiotics promotes a long-term protective effect against food allergies in the offspring.