Salmon nasal cartilage-derived proteoglycan complexes influence the gut microbiota and bacterial metabolites in mice

The effects of salmon nasal cartilage-derived proteoglycan complexes (SNC-PG) on the gut microbiota were examined by assessing changes in microbial composition, concentrations of short-chain fatty acids (SCFA), epithelial cell morphology, distal ileal gene expression levels, and fecal mucin content. Mice were assigned to one of two groups and fed either the standard AIN93G diet (control group) or the same diet supplemented with 0.04 % (w/w) SNC-PG (SNC-PG group) for 12 weeks. The SNC-PG diet increased fecal mucin content, reduced expression of inflammatory cytokine genes in the distal ileal mucosa, and high levels of acetic and butyric acid in the cecal contents compared with the control group. The relative abundance of Desulfobacterota, a bacterium that uses sulfate as an energy source, was higher in the SNC-PG group than in the control group. These findings suggest that SNC-PG intake may contribute to increased SCFA levels and fecal mucin content.