Gluten Friendly and fecal microbiota of celiac subjects: Evidence of a quali-quantitative changes in the community structure and in the top genera

Gut microbiota could play a significant role in the pathogenesis of Celiac Disease (CD), as there is a significant interaction between serology/histology, and microbiota. The exclusion of gluten still represents the only effective way to reduce the inflammatory cascade, although a gluten free diet does not guarantee the restoration of equilibrium in gut microbiota. Gluten Friendly (GF) technology is an alternative for CD, and a clinical study previously performed (Identifier: NCT03137862) showed that it could shape gut microbiota with some changes in its quali-quantitative composition. This paper represents a focus on the changes occurring on the fecal microbiota. Participants were stratified into four clusters, labeled as k1 (non-responders), k2, (partially responding to GF), k3 (responders), and gluten free (control). Diversity indices (Shannon, Simpson, Chao1) and β-diversity were calculated. Abundance and standardized changes at genus level (−1/0/+1) were also assessed, evaluating the taxa experiencing a significant change (P<0.05). Finally, microbial networks were reconstructed using Pearson correlations (|r| ≥ 0.5), with evaluation of density, average degree, and hub genera. In k3, there was an increase in Agathobacter , Butyricicoccus and a shift toward taxa, which could be, to some extent, regarded as beneficial. Non-responders (k1) showed a reduced connectivity, a loss of Ruminococcus and Barnesiella , and an increase in Intestinibacter and Tyzzerella . Partial responders (k2) displayed intermediate changes. In conclusion, GF could promote cluster-specific reorganization of microbial community and the emergence of some taxa, connected to the clinical outcomes, thus reinforcing the hypothesis that gut microbiota is a key-player in GF effect.