ALLERGIC rhinitis (AR) is a chronic respiratory inflammatory condition mediated by immunoglobulin E (IgE) upon exposure to inhaled allergens. Characterised by symptoms such as sneezing, rhinorrhea, nasal congestion, and pruritus, AR affects around 40% of the global population. Its impact on quality of life, productivity, and psychological well-being is substantial, compounded by the increasing incidence rate and socioeconomic burden. Traditional management strategies have limitations, necessitating the exploration of innovative treatments. Recent research highlights the role of intestinal microbiota in immune system regulation and AR development.
Studies reveal significant differences in gut microbiota composition between AR patients and healthy individuals. Reduced short-chain fatty acids (SCFAs), vital metabolites produced by gut bacteria, have been linked to worsened allergic inflammation. Probiotics and prebiotics, which modulate gut flora, offer promising therapeutic avenues. A notable clinical trial conducted in northwest China examined the effects of probiotics combined with prebiotics on seasonal AR patients. Over 90 days, participants reported improvements in nasal symptoms and reduced dependency on antihistamines, with changes in microbiota composition suggesting restored immune balance.
The trial found increased beneficial gut bacteria such as Lactobacillus and Bifidobacterium, alongside reduced pro-inflammatory species. Key immune markers, including TNF-α and INF-γ, were elevated, supporting a shift towards a Th1-mediated immune response and reduced Th17 activity. Additionally, SCFAs like acetate were positively correlated with symptom relief and immune modulation. These findings suggest that probiotics and prebiotics mitigate AR symptoms by influencing gut microbiota, metabolic pathways, and systemic immunity via the gut-lung axis.
While this research provides compelling evidence for microbial intervention, it highlights gaps requiring further exploration, such as optimal strains, doses, and the precise mechanisms underlying microbiota-immunity interactions. Despite these limitations, the study underscores the potential of probiotic-prebiotic therapies as effective, adjunctive treatments for AR, paving the way for personalised, microbiota-focused healthcare solutions.
Reference
Hou Y et al. Probiotics combined with prebiotics alleviated seasonal allergic rhinitis by altering the composition and metabolic function of intestinal microbiota: a prospective, randomized, double-blind, placebo-controlled clinical trial. Front Immunol. 2024;15:1439830.
