Cocoa Supplementation Alleviates Gliadin-Induced Intestinal Dysbiosis in a Mouse Model of Celiac Disease

Celiac disease (CeD) is a chronic immune-mediated enteropathy triggered by dietary gluten in genetically predisposed individuals which also entails intestinal dysbiosis. This hallmark microbial imbalance provides a rationale for exploring interventions that could modulate the gut ecosystem. Cocoa is a bioactive food rich in polyphenols, theobromine, and fiber, compounds known to have an influence on both immune function and gut microbiota composition. Here, we investigated the effects of cocoa supplementation on the gut microbial profile and predicted functionality in DQ8-D^d-villin-IL-15tg mice, genetically predisposed to CeD. Animals were assigned to a reference group receiving a gluten-free diet (GFD), a gluten-containing diet group (GLI), or the latter supplemented with defatted cocoa (GLI + COCOA) for 25 days. The cecal microbiota was analyzed via 16S rRNA sequencing, and functional pathways were inferred using PICRUSt2. Goblet cell counts and CeD-relevant autoantibodies were measured and correlated with microbial taxa. Cocoa supplementation partially attenuated gluten-induced dysbiosis, preserving beneficial taxa such as Akkermansia muciniphila and Lactobacillus species while reducing opportunistic and pro-inflammatory bacteria. Functional predictions suggested differences in the predicted microbial metabolic potential related to amino acid, vitamin, and phenolic compound metabolism. Cocoa also mitigated goblet cell loss and was inversely associated with anti-gliadin IgA levels. These findings suggest that cocoa, as an adjuvant to a GFD, could be of help in maintaining microbial homeostasis and intestinal health in CeD, supporting further studies to assess its translational potential.