The causality between intestinal flora and allergic diseases: Insights from a bi-directional two-sample Mendelian randomization analysis

Abstract

BackgroundGrowing evidence shows a significant association between intestinal flora and allergic diseases, specifically atopic dermatitis (AD), allergic rhinitis (AR), and allergic asthma (AA). However, the causality has not yet been clarified.ObjectiveWe conducted a bidirectional two-sample Mendelian randomization (TSMR) analysis to study the causal relationships between intestinal flora classification and AD, AR, or AA.Materials and methodsWe obtained summary data of intestinal flora, AD, AR, and AA from a genome-wide association research. The inverse-variance weighted method is the primary method for analyzing causality in the TSMR analysis. Several sensitivity analyses were conducted to examine the stability of TSMR results. Reverse TSMR analysis was also performed to assess whether there was a reverse causality.ResultsA total of 7 bacterial taxa associated with AD, AR, and AA were identified by the current TSMR analysis. Specifically, the genus Dialister(P=0.034)and genus Prevotella(P=0.047)were associated with a higher risk of AD, whereas class Coriobacteriia (P=0.034) and its child taxon, order Coriobacteriales (P=0.034) and family Coriobacteriaceae (P=0.034), all had a protective effect on AR. In addition, the family Victivallaceae (P=0.019) was identified as a risk factor for AR. We also noticed a positive association between the genus Holdemanella (P=0.046) and AA. The reverse TSMR analysis didn’t suggest any evidence of reverse causality from allergic diseases to the intestinal flora.ConclusionWe confirmed the causal relationship between intestinal flora and allergic diseases and provided an innovative perspective for research on allergic diseases: targeted regulation of dysregulation of specific bacterial taxa to prevent and treat AD, AR, and AA.

The relationship between prebiotic intake and allergic rhinitis

“…Previous studies have shown a causal relationship between gut microbiota and allergic diseases, as gut microbial dysbiosis can lead to abnormal immune reactions and promote the development of AR 5,6 . Prebiotics can regulate gut dysbiosis, 23 providing a new therapeutic approach for indirectly affecting the progression of AR by modulating the gut microenvironment through prebiotic intake.…”

“…Prebiotics Previous studies have shown a causal relationship between gut microbiota and allergic diseases, as gut microbial dysbiosis can lead to abnormal immune reactions and promote the development of AR. 5,6 Prebiotics can regulate gut dysbiosis, 23 providing a new therapeutic approach for indirectly affecting the progression of AR by modulating the gut microenvironment through prebiotic intake. The advantage of prebiotics lies in their selective fermentation by bifidobacteria or lactobacilli, dependent on stimulating the host's own bifidobacteria or lactobacilli populations.…”

“…In recent years, the relationship between gut microbiota and AR has drawn wide attention. Studies have shown that gut microbiota dysbiosis is associated with immune‐mediated diseases and may cause immune system dysregulation, thereby promoting the occurrence of AR 5–7 . Over the past few decades, there has been a significant increase in the prevalence of allergic diseases such as asthma, eczema, food allergies, and AR worldwide.…”

The causal relationship between gut microbiota and immune skin diseases: a bidirectional Mendelian randomization

“…(2) A linkage disequilibrium (LD) analysis (R2 < 0.001, clumping distance = 10,000kb) was performed to satisfy the MR hypothesis. It is important to avoid weak instrument bias when inferring causal relationships, we used the formula F = β 2 exposure/SE 2 exposure to calculate the intensity of IVs [19][20][21] and excluded IVs with F < 10 (23). GWAS summary statistics for skin diseases were extracted from the FinnGen research project (https://r5.…”

Colon-Hydro-Therapie: Ausleitung von innen

“…Daher stellt ein gesunder Darm ein Schlüsselelement zu mehr Gesundheit und Wohlbefinden im Allgemeinen dar. So haben Aufbaustudien gezeigt, dass Menschen mit einer gesunden Darmflora deutlich weniger anfällig für Allergien und Unverträglichkeiten sind [ 1 , 2 ]. Das ist deshalb so, weil die nützlichen Darmbakterien die vorderste Front unseres Körperabwehrsystems darstellen [ 3 ].…”