Allergic rhinitis (AR) is a health problem characterised by an inflammatory reaction in the nasal mucosa mediated by immunoglobulin (Ig) E and resulting from exposure to environmental allergens, such as pollen and dust mites. AR symptoms can significantly affect the quality of life of patients suffering from AR, causing substantial direct health care costs and indirect costs due to absenteeism from work. The effects of pharmacological treatments are not always fully effective and have adverse effects, resulting in a significant proportion of AR patients continuing to experience symptoms or being dissatisfied. Considering the relationship between AR and intestinal microbiota (IM), the use of probiotics, live microorganisms that, when consumed in adequate amounts, confer beneficial effects on the host, emerges as a potential strategy to prevent or treat certain allergies. There are different mechanisms of action by which probiotics may exert their effects on the treatment or prevention of allergies through modulation of the immune system and stimulation of tolerance. Probiotics promote a change in IM. In addition, probiotics stimulate gut-associated lymphoid tissue, modulating inflammation and immune reactions present in AR, promoting a more favourable profile by increasing the production of the modulatory cytokines IL-10 and TGFβ by Treg cells. Probiotics can restore the Th1:Th2 balance by inducing Th1 responses through the production of IL-12 and interferon (IFN)-γ, or by suppressing Th2 responses through the depletion of IL-4. In addition, probiotics may exert immunomodulatory effects through stimulating mucosal IgA production. The hypothesis of the present study is that supplementation with the probiotic Bifidobacterium longum ES1 and/or with the heat treated version of ES1 will decrease the symptomatology associated with AR and improve the quality of life of individuals by modulating IM and potentiating Treg cells and the Th1 response. The main objective of the present study is to determine the effects of supplementation with the probiotic Bifidobacterium longum ES1 and the heat treated version of ES1 (HT-ES1) on the symptoms associated with AR. The secondary objectives of the study are to determine the effects of the treatments over: 1) Quality of life; 2) Blood immunological markers (IFN-γ, IL-12, IL-10, TGF-β, IgE, IL-4, IL-13, IL-19 and IL-8); 3) Faecal immunological marker IgA; 4)Faecal microbiota composition.
Age range
18 Years – 60 Years
Sex
ALL
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Combined Symptoms and Medication Score
Timeframe: Daily for the thirteen weeks of the study.