Disease ⇒ Allergy {40000209}

Shared Reference Notes

• [1.1] [#Short Chain Fatty Acid] 
  - Decreases in the bacterially fermented metabolites of glycans, SCFAs, have been associated with IgE-mediated food allergy, providing an example of how dietary-driven microbiota changes can influence human health and disease
• [1.2] 
  - #Cutibacterium > ferments hexoses > Embden–Meyerhof pathway > produce #Pyruvate > metabolized into propionate > reduce antigen presentation on dendritic cells as > GPR41-dependent modulation of hematopoiesis and affected allergic diseases in a mouse model
• [1.3] [#Atopic Dermatitis] [#High fibre diet] 
  - Epidemiological evidence indicates that children suffering from allergies have lower levels of dietary fibre-derived short-chain fatty acids (SCFA). Using an experimental model of AD-like skin inflammation, - a fermentable fibre-rich diet alleviates systemic allergen sensitization and disease severity. - particularly butyrate, which strengthens skin barrier function by altering mitochondrial metabolism of epidermal keratinocytes and the production of key structural components.
• [1.4] [#Diabetes Type 1, #Infantile eczema] 
  #Infants treated with antibiotic > The early use of this treatment has been associated with higher risks of allergic diseases, eczema , and #Obesity, and type 1 diabetes
• - #Exposure to pets increases the abundance of Ruminococcus and Oscillospira species, which may protect against allergic disorders and #Obesity in children
• [1.5] 
  - #Siblings in the home to be one of the most important determinants of the developing microbiota in both the airway and gut, with significant differences in alpha diversity, beta diversity, and relative abundances of the most abundant taxa, with the specific associations being particularly apparent during the first year of life. - The age gap to the closest older sibling was more important than the number of older #Siblings. The signature of having #Siblings in the gut microbiota at 1 year was associated with protection against #Asthma at 6 years of age, while no associations were found for allergy.
• [1.6] [#Inulin] 
  - diet of #Inulin fibre alters the composition of the mouse microbiota and the levels of microbiota-derived metabolites, notably #Bile Acids. - This metabolomic shift is associated with type 2 inflammation in the intestine and lungs, characterized by IL-33 production, activation of group 2 innate lymphoid cells and eosinophilia. - dietary #Inulin fibre triggers microbiota-derived #Cholic acid and type 2 inflammation at barrier surfaces
• [1.7] 
  - #Blautia, #Faecalibacterium, and #Dorea levels were consistently more abundant in 8-year-olds with allergy than in #Children without allergy. - #Faecalibacterium abundance was correlated with IL-10 and FOXP3 mRNA levels.
• [1.8] [#Diabetes Type 2] 
  - A disturbed #Proteobacteria microbiota has been previously associated with #Psoriasis, eczema and diabetic foot ulcers, with greater #Proteobacteria diversity correlated with T-helper1, interleukin-10 and anti-inflammatory immune responses that were protective against allergic inflammation.
• [1.9] [#Anaerostipes hadrus, #Blautia wexlerae, #Clostridium innocuum, #Eggerthella lenta, #Enterococcus faecalis, #Escherichia coli, #Eubacterium hallii, #Fusicatenibacter saccharivorans, #Tyzzerella nexilis] 
  - depletions in the bacterial species A. hadrus, F. saccharivorans, E. hallii, and B. wexlerae in participants who later developed allergic diseases, as well as enrichments in E. lenta, C. innocuum, E. faecalis, E. coli, and T. nexilis in these participants.
• [#Anaerostipes hadrus, #Blautia wexlerae, #Eubacterium hallii, #Fusicatenibacter saccharivorans] [#Short Chain Fatty Acid] - The depleted bacterial populations are known short-chain fatty acid (SCFA) producers, notably the #Butyrate producers A. hadrus, E. hallii, and F. saccharivorans and the #Acetate producer B. wexlerae - depletion of #Butyrate in allergy-prone participants significant associations between A. hadrus and F. saccharivorans respective relative abundance and #Butyrate concentration.
• - Several maturation-dependent metabolites were disturbed in #Children who developed allergies with three biogenic amines, namely #Phenylethylamine, #Tryptamine, and #Tyramine, also demonstrating high correlations with disrupted microbial pathways. - This Trace amines (TAs) have a very high affinity for TA-associated receptors (TAARs), a class of G-coupled protein receptors found on both intestinal and immune cells, and TAAR ligation has been demonstrated to increase intestinal cell oxidative stress and immune cell activation. - their accumulation promotes bacterial adherence to intestinal cells, likely perpetuating this inflammatory response
• - imbalances in functional pathways indicative of dysbiosis were associated with reduced predicted age and elevated risk of allergy. -These included a breakdown of mucous integrity via elevated #Sulfur reduction and diminished #Sulfur oxidation pathways, elevated oxidation levels and subsequent availability of oxidized monosaccharides, as well as reduced potential for secondary fermentation.
• [#Food Allergy] [#Akkermansia muciniphila] - A. muciniphila was reported to be decreased in the faecal microbiota of severe asthmatic patients, and oral supplementation of A. muciniphila to the native complex gut microbiota was able to modulate the immunophenotype and protect mice from allergic airway inflammation. - By contrast, the abundance of A. muciniphila or its family #Verrucomicrobiaceae has been reported to be transiently increased in the faeces of food allergic #Infants by the age of 13–18 months
• [#Akkermansia muciniphila] - A. muciniphila in the maintenance of the allergic type-2 response by promoting Th2 cells under fibre-rich conditions and type-2 innate cells under fibre deprivation.
• [#Akkermansia muciniphila] - the enhanced mucin-degrading activity of A. muciniphila in FF mice may be required as an additional microbial trigger to promote the breakdown of oral tolerance, probably through increased innate type-2 responses.
• [1.11] 
  - #Peanut allergy-bound #Children had different abundance trajectories of #Clostridium sensu stricto 1 sp. and #Bifidobacterium sp. , with #Butyrate and #Isovalerate decreasing over time.
• - Metabolites associated with #Peanut allergy development clustered within the #Histidine metabolism pathway. - Positive correlations between microbiota, #Butyrate, and #Isovalerate and negative correlations with #Histamine marked the #Peanut allergy-free network.
• [1.12] [#Antibiotic Therapy, #Infants, #Mother-infant] 
  - Antibiotic exposure during #Pregnancy was associated with preschool #Asthma, wheezing, #Allergic rhinoconjunctivitis and any allergic disease in offspring up to age 3 years.
• [1.13] [#Atopic Dermatitis, #Atopy] 
  - In #Children with AD, there was a significantly lower #Vitamin D level at age 2 and 4, but a significantly higher prevalence of food and mite sensitization at all ages in comparison with HC. - #Vitamin D level was found to be inversely related to the prevalence of allergen sensitization at age 4

References Notes