Prevention Of Allergic Symptoms Research Articles

The role of carotenoid intake in food allergy prevention.

Abstract Carotenoids are reported to play an important role in various physiological processes. Carotenoids quench reactive oxygen species and play a role in the prevention of development of chronic diseases and certain types of allergic diseases. The intake of β-carotene, which is one of the carotenoids, can improve allergic symptoms through inhibition of antigen-specific IgE antibody production, degranulation and the release of chemical mediators from mast cells or basophils. The retinoic acid derived from β-carotene is known to play an important role in inducing oral tolerance in gut-associated lymphoid tissue. The intake of β-carotene inhibits oral sensitization and the onset of IgE-dependent immediate type allergy. The intake of carotenoids has been reported to be important in the prevention of allergic symptoms, including allergic sensitization, asthma and eczema.

The Importance of Allergen Avoidance in High Risk Infants and Sensitized Patients: A Meta-analysis Study.

PurposeAt this time, there is uncertainty regarding whether allergen avoidance is the most appropriate strategy for managing or preventing allergies. The purpose of this study was to evaluate the effectiveness of allergen avoidance in the prevention of allergic symptoms in previously sensitized patients and newborns that have the potential to develop allergies.MethodsWe performed online searches of articles published from January 1980 to December 2012 in PubMed and The Cochrane Central Register of Controlled Trials, and selected articles involving randomized controlled trials (RCTs) and allergen avoidance. The parameters used to determine allergenic potential in newborns included the risk ratio (RR) of eczema, asthma, rhinitis, wheeze, and cough. The methods employed to evaluate previously sensitized patients were the standardized mean difference (SMD) of forced expiratory volume in 1 second (FEV1) and peak expiratory flow rate (PEFR). Data quality was assessed using the Jadad scale.ResultsA total of 14 RCTs were identified. Meta-analysis demonstrated that allergen avoidance for newborns did not reduce the subsequent incidence of allergic diseases (eczema, P=0.21; rhinitis, P=0.3; cough, P=0.1) but significantly reduced the incidence of asthma and wheezing in high-risk infants (asthma, P=0.03; wheeze, P=0.0004). However, previously sensitized patients who reduced their exposure to known allergens did not show improvement in their lung functions (FEV1, P=0.3; PEFR morning, P=0.53; PEFR evening, P=0.2; PEFR, P=0.29).ConclusionsAllergen avoidance may not always be successful in preventing allergic symptoms. However, rigorous methodological studies are required to confirm this hypothesis.

A topical microemulsion for the prevention of allergic rhinitis symptoms: results of a randomized, controlled, double-blind, parallel group, multicentre, multinational clinical trial (Nares study)

BackgroundSince barrier protection measures to avoid contact with allergens are being increasingly developed, we assessed the clinical efficacy and tolerability of a topical nasal microemulsion made of glycerol esters in patients with allergic rhinitis.MethodsRandomized, controlled, double-blind, parallel group, multicentre, multinational clinical trial in which adult patients with allergic rhinitis or rhinoconjunctivitis due to sensitization to birch, grass or olive tree pollens received treatment with topical microemulsion or placebo during the pollen seasons. Efficacy variables included scores in the mini-RQLQ questionnaire, number and severity of nasal, ocular and lung signs and symptoms, need for symptomatic medications and patients’ satisfaction with treatment. Adverse events were also recorded.ResultsDemographic characteristics were homogeneous between groups and mini-RQLQ scores did not differ significantly at baseline (visit 1). From symptoms recorded in the diary cards, the ME group showed statistically significant better scores for nasal congestion (0.72 vs. 1.01; p = 0.017) and mean total nasal symptoms (0.7 vs. 0.9; p = 0.045). At visit 2 (pollen season), lower values were observed in the mini-RQLQ in the ME group, although there were no statistically significant differences between groups in both full analysis set (FAS) and patients completing treatment (PPS) populations. The results obtained in the nasal symptoms domain of the mini-RQLQ at visit 2 showed the highest difference (−0.43; 95% CI: -0.88 to 0.02) for the ME group in the FAS population. The topical microemulsion was safe and well tolerated and no major discomforts were observed. Satisfaction rating with the treatment was similar between the groups.ConclusionsThe topical application of the microemulsion is a feasible and safe therapy in the prevention of allergic symptoms, particularly nasal congestion.Trial registrationClinicalTrials.gov Identifier: NCT01478425

Galectin‐9 induced by dietary synbiotics is involved in suppression of allergic symptoms in mice and humans

Prebiotic galacto- and fructo-oligosaccharides (scGOS/lcFOS) resembling non-digestible oligosaccharides in human milk reduce the development of atopic disorders. However, the underlying mechanisms are still unclear. Galectins are soluble-type lectins recognizing β-galactoside containing glycans. Galectin-9 has been shown to regulate mast cell degranulation and T-cell differentiation. In this study, the involvement of galectin-9 as a mechanism by which scGOS/lcFOS in combination with Bifidobacterium breve M-16V protects against acute allergic symptoms was investigated. Mice were sensitized orally to whey, while being fed with a diet containing scGOS/lcFOS and Bifidobacterium breve M-16V (GF/Bb) or a control diet. Galectin-9 expression was determined by immunohistochemistry in the intestine and measured in the serum by ELISA. T-cell differentiation was investigated in the mesenteric lymph nodes (MLN) as well as in galectin-9-exposed peripheral blood mononuclear cells (PBMC) cultures. Sera of the mice were evaluated for the capacity to suppress mast cell degranulation using a RBL-2H3 degranulation assay. In addition, in a double-blind, placebo-controlled multicenter trial, galectin-9 levels were measured in the sera of 90 infants with atopic dermatitis who received hydrolyzed formulae with or without GF/Bb. Galectin-9 expression by intestinal epithelial cells and serum galectin-9 levels were increased in mice and humans following dietary intervention with GF/Bb and correlated with reduced acute allergic skin reaction and mast cell degranulation. In addition, GF/Bb enhanced T(h)1- and T(reg)-cell differentiation in MLN and in PBMC cultures exposed to galectin-9. Dietary supplementation with GF/Bb enhances serum galectin-9 levels, which associates with the prevention of allergic symptoms.