Role of the dietary components in food allergy: A comprehensive review

Purified components of red-edge tea polysaccharide alleviate food allergy in mice by regulating intestinal homeostasis

Previous studies found red-edge tea polysaccharides (RETPS)-3 and 4 have anti-allergic effects. To investigate the anti-food allergy activity of the RETPS-3/4, the ovalbumin-induced Balb/c mouse food allergy model was established. Food allergy symptoms, serum inflammatory factors, spleen and intestinal pathology were analyzed. The proportion of lymphocyte clusters was measured by flow cytometry. The intestinal flora of mice was examined using the 16S rDNA method. The results showed that RETPS-3/4 alleviated food allergy symptoms in mice, relieved intestinal injury, and reduced the contents of ovalbumin-specific immunoglobulin E, mast cell protease, and histamine in the serum of mice. In addition, RETPS-3/4 regulated the proportion of Th2 cells in mouse mesenteric lymph nodes and the abundance of Lactobacillus_muris and Prevotella. These results showed that RETPS-3/4 had anti-food allergy activity and could be developed as a functional anti-food allergy product.

Terpenoids, a Rising Star in Bioactive Constituents for Alleviating Food Allergy: A Review about the Potential Mechanism, Preparation, and Application

Food allergies affect approximately 2.5% of the global population, with a notable increase in prevalence observed each year. Terpenoids, a class of natural bioactive constituents, have been widely utilized in the management of immune- and inflammation-related disorders, and their potential in alleviating food allergies is increasingly being recognized. This article summarizes various terpenoids derived from plant, fungal, and marine sources. Among them, triterpenoids, such as oleanolic acid, ursolic acid, and lupeol, possess the highest proportion and bioactivity in alleviating food allergy. Additionally, the mechanisms by which terpenoids may mitigate allergic diseases were categorically outlined, focusing on their roles in epithelial mucosal barrier function, immunomodulatory effects during the sensitization phase, inhibition of effector cells, oxidative stress, and regulation of microbial homeostasis. Finally, the advantages and limitations of natural extraction and artificial synthesis methods were compared, and the application of terpenoids in the food industry were also discussed. This article serves as a useful reference for the development of methods or functional foods based on terpenoids, which could represent a promising avenue for alleviating food allergy.

The NLRP3 inflammasome in allergic diseases: mechanisms and therapeutic implications

In recent years, there has been a global increase in the prevalence of allergic diseases, including allergic rhinitis, chronic rhinosinusitis, allergic asthma, atopic dermatitis, allergic conjunctivitis, and food allergies. Since the pathogenic mechanisms of these allergic diseases are not yet fully understood, targeted and effective therapies are lacking. The NLRP3 inflammasome, a multiprotein complex implicated in various inflammatory diseases, can be activated by diverse stimuli. It assembles into NLRP3 inflammasome complexes through conformational changes, initiating the proteolytic cleavage of dormant procaspase-1 into active caspase-1 and promoting the maturation of inflammatory cytokines, including IL-1β and IL-18. Dysfunction of the NLRP3 inflammasome may serve as a key driver of inflammatory diseases, leading to pyroptosis and amplifying the local inflammatory response. As preliminarily demonstrated, specific NLRP3 inflammatory vesicle inhibitors play refectory roles in animal models of allergic diseases, and it is believed that specific NLRP3 inflammasome inhibitors may be potential therapeutic agents for allergic diseases. This review highlights the progress of research on the NLRP3 inflammasome in allergic diseases, explores its contribution to different types of allergic diseases, and identifies promising clinical targets for intervention.

The potential of orally exposed risk factors and constituents aggravating food allergy: Possible mechanism and target cells

Food allergy is a significant concern for the health of humans worldwide. In addition to dietary exposure of food allergens, genetic and environmental factors also play an important role in the development of food allergy. However, only the tip of the iceberg of risk factors in food allergy has been identified. The importance of food allergy caused by orally exposed risk factors and constituents, including veterinary drugs, pesticides, processed foods/derivatives, nanoparticles, microplastics, pathogens, toxins, food additives, dietary intake of salt/sugar/total fat, vitamin D, and therapeutic drugs, are highlighted and discussed in this review. Moreover, the epithelial barrier hypothesis, which is closely associated with the occurrence of food allergy, is also introduced. Additionally, several orally exposed risk factors and constituents that have been reported to disrupt the epithelial barrier are elucidated. Finally, the possible mechanisms and key immune cells of orally exposed risk factors and constituents in aggravating food allergy are overviewed. Further work should be conducted to define the specific mechanism by which these risk factors and constituents are driving food allergy, which will be of central importance to the targeted therapy of food allergy.

Reducing the Allergenicity of β-Lactoglobulin by Covalent Modification with Different Contents of Epigallocatechin Gallate (EGCG): In Vitro and In Vivo Studies

β-Lactoglobulin (βLG) is a major allergen in bovine milk protein. This study was designed to investigate changes in βLG structure, digestibility, and allergenicity induced by covalent binding modification with different contents of (-)-epigallocatechin 3-gallate (EGCG). The reaction of EGCG conjugation with βLG reached saturation at a molar ratio of 1:60 βLG:EGCG. Conjugation with EGCG altered the βLG structure, decreased IgE-binding capacity, and increased digestibility in a dose-dependent manner. In vivo studies showed that covalent conjugation with EGCG can reduce βLG-induced allergic symptoms with reducing levels of IgE, histamine, and mast cell protease-1 (mMCP-1) and the percentage of sensitized mast cells. Allergenicity was reduced more effectively in saturated βLG-EGCG conjugates compared to semisaturated conjugates. Observed changes in IFN-γ, IL-4, IL-5, IL-10, and TGF-β levels suggested that βLG-EGCG conjugates were able to promote Th1/Th2 immune balance. These findings further our understanding of the relationship between the degree of polyphenol conjugation and the allergenicity of food allergens.

Elimination diet in food allergy: friend or foe?

OBJECTIVES

To review and discuss the role of an elimination diet in food-allergic children, emphasizing nutritional aspects for a better practical approach.

SOURCES

Non-systematic review of the literature.

FINDINGS

Under an elimination diet, food-allergic patients may suffer from growth impairment or obesity and compromised quality of life. Disease phenotype, age, type, number of foods excluded, comorbidities, eating difficulties, economic status, and food availability must be considered for an appropriate diet prescription. Diet quality encompasses diversity and degree of food processing, which may alter immune regulation.

CONCLUSIONS

A friendly food elimination diet prescription depends on a multidisciplinary approach beyond macro and micronutrients.

Inhibitory effect of rosmarinic acid on IgE-trigged mast cell degranulation in vitro and in vivo

BACKGROUND

Rosmarinic acid (RA), a polyphenol from edible-medical Lamiaceae herbs, is known to possess a variety of pharmacological activity, like anti-inflammatory, hepatoprotective and immunoregulation activities.

METHODS AND RESULTS

Hereon, we investigated the anti-allergic activity of RA on immunoglobulin E (IgE)-mediated anaphylaxis responses in rat basophilic leukemia (RBL)-2H3 mast cell. RA hindered the morphological changes of IgE-induced degranulated RBL-2H3 cells. The release of two key biomarkers (β-hexosaminidase (β-HEX) and histamine) of IgE-induced degranulated mast cells was also remarkably down-regulated by RA intervention in a dose dependent manner. Moreover, RA inhibited IgE-induced ROS overproduction and flux of intracellular Ca2+ in IgE-mediated degranulated mast cells. The q-PCR analysis showed that the expressions of genes (COX 2, PGD 2, LTC 4, HDC, Nrf2, HO-1 and NQO1) involved in MAPK and oxidative stress signaling pathways were significantly regulated by RA intervention. Moreover, the degranulation inhibitory effect of rosmarinic acid was investigated on the anti-DNP IgE/DNP-HSA induced passive cutaneous anaphylaxis (PCA) mice model in vivo. It showed that RA significantly inhibited the PCA reaction and allergic edema of ears in anti-DNP IgE/DNP-HSA stimulated mice.

CONCLUSION

These findings suggest that RA has the potential to be used as a therapeutic candidate for allergic diseases by inhibiting mast cell degranulation. This indicates a possible role for RA in managing allergic reactions and related conditions.

Immunomodulatory effect of marine lipids on food allergy

Seafood is highly enriched in n-3 long-chain polyunsaturated fatty acids (n-3 LCPUFAs), particularly eicosapentaenoic acid (EPA, 20:5 n-3) and docosahexaenoic acid (DHA, 22:6 n-3), in contrast to the ultra-processed foods included in the modern Western diet that have high levels of n-6 linoleic acid (LA, 18:2 n-6), precursor for the pro-inflammatory n-6 arachidonic acid (ARA, 20:4 n-6). The capacity of marine lipids to reduce plasmatic triglycerides and blood pressure have been well-described. Moreover, recent studies have also raised evidence of a potential regulatory action of marine lipids on inflammation, the immune system, and food allergy (FA). FA is considered one of the main concerns to become life threatening in food safety. The prevalence of this emerging global problem has been increasing during the last two decades, especially in industrialized countries. About a 6-8% of young children and 2-4% of adults is estimated to be affected by FA. The main objective of the current study is to update the existing knowledge, but also the limitations, on the potential impact of marine lipids and their lipid mediators in regulating immunity, inflammation, and ultimately, food allergies. In particular, the focus is on the effect of marine lipids in modulating the key factors that control the sensitization and effector phases of FA, including gut microbiota (GM), inflammation, and immune system response. Results in animal models highlight the positive effect that consuming marine lipids, whether as a supplement or through seafood consumption, may have a relevant role in improving gut dysbiosis and inflammation, and preventing or reducing the severity of FA. However, more systematic studies in humans are needed to optimize such beneficial actions to each particular FA, age, and medical condition to reach an effective clinical application of marine lipids to improve FAs and their outcomes.

Leuconostoc mesenteroides WHH1141 ameliorates ovalbumin-induced food allergy in mice

Food allergy (FA) is acknowledged as a significant public health and food safety issue, due to its manifestation as an amplified immune reaction to food antigens. Recently, probiotics within Lactobacillus and Bifidobacterium have been highlighted as a promising strategy against allergic disease by modulating the balance of Th1/Th2 responses. However, the allergy-alleviating effects of probiotic Leuconostoc mesenteroides strains are unknown. Therefore, this study investigated the potentials of eleven L. mesenteroides strains on the Th1/Th2 balance in vitro by evaluating the expression patterns of interferon-gamma (IFN-γ) (Th1 cytokine) and interleukin-4 (IL-4) (Th2 cytokine) in mesenteric lymph node-derived lymphocytes from ovalbumin (OVA)-sensitized mice. Among strains, WHH1141 incubation caused the highest IFN-γ/IL-4 ratio. Oral administration of WHH1141 (1 × 109  CFU/mL) in the OVA-induced FA mouse model for 40 days improved the weight loss and FA pathological symptoms and normalized the serum immunoglobulin E levels. Meanwhile, the OVA-induced elevated gene expressions of cytokines (IL-4, IL-5, and IL-13) and tight-junction proteins (ZO-1 and Occludin) and levels of cytokines (IL-4, IL-5, and IL-13) and histamine in the jejunum were restored by WHH1141. Furthermore, WHH1141 reversed the reduced gut microbial diversity and short-chain fatty acid (SCFA) levels, specifically increased Bacteroidota abundance, and decreased Firmicutes abundance in OVA-induced mice. Overall, these findings suggest that WHH1141 exerts FA-alleviating effects on OVA-induced mice, which is involved with the inhibition of the jejunal Th2 immune responses and the modulation of gut microbiome composition and SCFA productions. PRACTICAL APPLICATION: Leuconostoc mesenteroides WHH1141 with FA-alleviating potentials may be considered a promising approach in the mitigation of FA symptoms.

The Effect of Dietary Components of the Mediterranean Diet on Food Allergies: A Systematic Review

Allergies are a common and increasing health problem affecting millions of people worldwide. This increase is attributed to genetic predisposition, air pollution, climate change, lack of physical activity, and alterations in eating habits. The Mediterranean diet (MD), which includes a lot of fruits and vegetables, whole grains, legumes, nuts, olive oil, and fish, has been linked to a variety of health benefits, including a lower risk of chronic and allergic disease. This paper explores the effects of the dietary components of the MD on food allergies. Electronic databases PubMed, Scopus, Science Direct, and EBSCO were used to conduct this systematic review. Out of 696 studies initially identified, five human and four animal studies were included. Risk of bias was determined using the Office of Health Assessment and Translation tool. In human studies, when the intervention was given during pregnancy and lactation, a beneficial effect was observed. When the intervention was given during pregnancy and until birth or to the infant for six months, no effect was observed. The animal studies indicated a beneficial effect between the food components of the MD and food allergies. Although the results are promising, the limited number of studies highlights the need for more research.

Anti-Allergic Effect of Dietary Polyphenols Curcumin and Epigallocatechin Gallate via Anti-Degranulation in IgE/Antigen-Stimulated Mast Cell Model: A Lipidomics Perspective

Polyphenol-rich foods exhibit anti-allergic/-inflammatory properties. As major effector cells of allergies, mast cells undergo degranulation after activation and then initiate inflammatory responses. Key immune phenomena could be regulated by the production and metabolism of lipid mediators by mast cells. Here, we analyzed the antiallergic activities of two representative dietary polyphenols, curcumin and epigallocatechin gallate (EGCG), and traced their effects on cellular lipidome rewiring in the progression of degranulation. Both curcumin and EGCG significantly inhibited degranulation as they suppressed the release of β-hexosaminidase, interleukin-4, and tumor necrosis factor-α from the IgE/antigen-stimulated mast cell model. A comprehensive lipidomics study involving 957 identified lipid species revealed that although the lipidome remodeling patterns (lipid response and composition) of curcumin intervention were considerably similar to those of EGCG, lipid metabolism was more potently disturbed by curcumin. Seventy-eight percent of significant differential lipids upon IgE/antigen stimulation could be regulated by curcumin/EGCG. LPC-O 22:0 was defined as a potential biomarker for its sensitivity to IgE/antigen stimulation and curcumin/EGCG intervention. The key changes in diacylglycerols, fatty acids, and bismonoacylglycerophosphates provided clues that cell signaling disturbances could be associated with curcumin/EGCG intervention. Our work supplies a novel perspective for understanding curcumin/EGCG involvement in antianaphylaxis and helps guide future attempts to use dietary polyphenols.

Epitope Mapping of Lysozyme Using the Chinese Egg-Allergic Sera at Both Pooled and Individual Levels

To accurately map the B-cell linear epitopes of lysozyme (LYS) in eggs, five bioinformatics tools were first used to obtain the mimotopes. Afterward, based on the Chinese egg-allergic sera samples screened by the indirect enzyme-linked immunosorbent, the epitopes possessing the capability of binding to IgG/IgE were mapped at both pooled and individual levels by using overlapping peptides covering the complete amino acid sequence of LYS. Six B-cell linear epitopes and two dominant B-cell linear epitopes that could bind to LYS-sIgG were mapped for the first time. Seven IgE-binding epitopes and three dominant IgE-binding epitopes were also obtained. Furthermore, AA31-34 and AA88-91 were the shared dominant epitopes of LYS-sIgG and LYS-sIgE at pooled and individual levels. Overall, the mapped B-cell linear epitopes filled in the gaps in the study of LYS epitopes, and the results may provide theoretical support for the following immunotherapy of egg allergy.

Early-life exposure to air pollution associated with food allergy in children: Implications for 'one allergy' concept

BACKGROUND

The rapid increase of food allergy (FA) has become the "second wave" of allergy epidemic and is now a major global public health concern. Mounting evidence indicates that early life exposure to air pollution is associated with the "first wave" of allergy epidemic (including asthma, allergic rhinitis and eczema) in children, but little is known about its association with FA.

OBJECTIVES

We hypothesize FA has triple exposure pathways, gut-skin-airway, and investigate the effects of airway exposure to outdoor and indoor air pollution on childhood FA.

METHODS

A cohort study of 2598 preschool children aged 3-6 years old was conducted in Changsha, China. The prevalence of FA was surveyed using a standard questionnaire by International Study of Asthma and Allergies in Childhood (ISAAC). Exposure to indoor air pollution was assessed by four indicators: new furniture, redecoration, mold or dampness, and window condensation. Exposure to outdoor air pollution was evaluated by the concentrations of PM10, SO2 and NO2, which were obtained from the monitored stations. Both prenatal and postnatal exposure windows were considered. The association between exposure to outdoor/indoor air pollution and childhood FA was estimated by multiple logistic regression models using odds ratio (OR) and a 95% confidence interval (CI).

RESULTS

A total of 14.9% children reported FA. The prevalence was significantly associated with exposure to indoor air pollution, OR (95% CI) = 1.93 (1.35-2.75) for prenatal exposure to mold/dampness and 1.49 (1.07-2.10) and 1.41 (1.04-1.89) respectively for postnatal exposure to new furniture and window condensation. The prevalence of FA was also associated with prenatal and postnatal exposure to outdoor air pollution, particularly the traffic-related air pollutant NO2, with adjusted ORs (95% Cls) respectively 1.24 (1.00-1.54) and 1.38 (1.03-1.85) per interquartile range (IQR) increase. Sensitivity analysis showed that the association between outdoor/indoor air pollution and childhood FA was significant only in young children aged 3-4 years.

CONCLUSION

Early-life exposure to high levels of outdoor and indoor air pollution in China due to the rapid economic growth and fast urbanization in the past decades may contribute to the rapid increase of food allergy (FA) in children. Our study indicates that, in addition to gut and skin, airway may be a new route of food sensitization. Air pollution leads to the first and second waves of allergy epidemics, suggesting a concept of 'one allergy' disease.

Oleuropein Prevents OVA-Induced Food Allergy in Mice by Enhancing the Intestinal Epithelial Barrier and Remodeling the Intestinal Flora

SCOPE

This study assesses whether oleuropein prevents ovalbumin (OVA)-induced food allergy (FA) and investigates the underlying mechanisms.

METHODS AND RESULTS

A Balb/c FA mouse model is established and maintained for 7 weeks. The subjects are administered OVA by oral gavage to induce FA and supplemented with different oleuropein doses (1.00-20.00 mg kg^-1 per day) to evaluate its preventative efficacy. The results indicate that oleuropein effectively alleviates OVA-induced allergy symptoms and promotes temperature elevation in sensitized mice. The secretion of serology-specific OVA-immunoglobulin (Ig)E, OVA-IgG, and histamine is inhibited in the sensitized mice. Oleuropein dramatically upregulates the expression of intestinal tight junction (TJ) proteins, regenerating gene (Reg) IIIγ, and interleukin (IL)-22, enhancing the physical and biochemical barrier function of the intestinal epithelium. Additionally, oleuropein improves the immune homeostasis of the intestinal epithelium by affecting the function of mucosal mast cells and regulatory T (Treg) cells. The disordered intestinal flora of the sensitized mice also improves after oleuropein administration.

CONCLUSIONS

These findings suggest that oleuropein prevents FA by enhancing intestinal epithelial barrier function and improving immune homeostasis and intestinal flora in sensitized mice. Therefore, diets rich in oleuropein should be recommended for people with FA.

Ultra-processed foods and allergic symptoms among children and adults in the United States: A population-based analysis of NHANES 2005-2006

Design

There is a strong correlation between dietary intake and allergic diseases. Ultra-processed foods (UPFs) are gradually becoming dominant worldwide and causing health problems for children and adults. We hope to determine whether links exist between UPFs and allergic symptoms.

Methods

We investigated data from 2,736 children (16-19 years) and 4,256 adults (≥20 years) from the National Health and Nutritional Examination Survey (NHANES) 2005-2006. The associations between the mean UPFs contribution to total energy intake and all allergic symptoms (IgE, current asthma, allergy, rash, sneeze, wheeze, eczema, and hay fever) were estimated by weighted multivariate logistic regression.

Results

Logistic regression analysis showed UFPs were negatively associated with IgE levels in children. Those with higher quartiles had a reduced risk from 16% (OR, 0.84, 95%CI, 0.55 to 1.28) to 34% (OR, 0.66, 95%CI, 0.49 to 0.89), p for trend = 0.006. UPFs were also positively related to current asthma in children with an increased risk of 11% (OR, 1.11, 95%CI, 0.79 to 1.56) to 76% (OR, 1.76, 95%CI, 1.10 to 2.82), p for trend = 0.0393. UPFs were also associated with eczema in girls. But there was no association observed between UPFs and allergic symptoms in adults.

Conclusion

Our results suggested that UPFs assessed by the NOVA system were associated with IgE, current asthma in children, and eczema in girls. These results further support the need to test the association of modern dietary patterns with allergic symptoms.

Allergic Inflammation: Effect of Propolis and Its Flavonoids

The incidence of allergic diseases and their complications are increasing worldwide. Today, people increasingly use natural products, which has been termed a "return to nature". Natural products with healing properties, especially those obtained from plants and bees, have been used in the prevention and treatment of numerous chronic diseases, including allergy and/or inflammation. Propolis is a multi-component resin rich in flavonoids, collected and transformed by honeybees from buds and plant wounds for the construction and adaptation of their nests. This article describes the current views regarding the possible mechanisms and multiple benefits of flavonoids in combating allergy and allergy-related complications. These benefits arise from flavonoid anti-allergic, anti-inflammatory, antioxidative, and wound healing activities and their effects on microbe-immune system interactions in developing host responses to different allergens. Finally, this article presents various aspects of allergy pathobiology and possible molecular approaches in their treatment. Possible mechanisms regarding the antiallergic action of propolis on the microbiota of the digestive and respiratory tracts and skin diseases as a method to selectively remove allergenic molecules by the process of bacterial biotransformation are also reported.

Bacterial Cellulose as a Versatile Biomaterial for Wound Dressing Application

Chronic ulcers are among the main causes of morbidity and mortality due to the high probability of infection and sepsis and therefore exert a significant impact on public health resources. Numerous types of dressings are used for the treatment of skin ulcers-each with different advantages and disadvantages. Bacterial cellulose (BC) has received enormous interest in the cosmetic, pharmaceutical, and medical fields due to its biological, physical, and mechanical characteristics, which enable the creation of polymer composites and blends with broad applications. In the medical field, BC was at first used in wound dressings, tissue regeneration, and artificial blood vessels. This material is suitable for treating various skin diseases due its considerable fluid retention and medication loading properties. BC membranes are used as a temporary dressing for skin treatments due to their excellent fit to the body, reduction in pain, and acceleration of epithelial regeneration. BC-based composites and blends have been evaluated and synthesized both in vitro and in vivo to create an ideal microenvironment for wound healing. This review describes different methods of producing and handling BC for use in the medical field and highlights the qualities of BC in detail with emphasis on biomedical reports that demonstrate its utility. Moreover, it gives an account of biomedical applications, especially for tissue engineering and wound dressing materials reported until date. This review also includes patents of BC applied as a wound dressing material.