Protein-rich food matrices from alternative and conventional sources differentially shape gut microbiota, metabolic...

The functional consequences of consuming conventional and alternative protein rich food matrices remain poorly understood. This study characterized diverse protein rich food matrices and investigated their effect on gut microbiota, muscle protein synthesis, and host metabolic function in rats. Arthropods and lentils contained chitin, resistant starch, polyphenols, and antioxidant activity, whereas egg and picanha were enriched in cholesterol and precursors of trimethylamine N-oxide (TMAO). Lentils and crickets consumption resulted in the lowest fat mass gain, glucose area under the curve and serum lipopolysaccharide (LPS) concentration and lentils the highest fecal butyrate. Gut microbiota alpha diversity was similar among rats fed casein, cricket, acocil, and beef diets, whereas diets containing higher amounts and different types of fat, including egg, picanha, and chinicuil, reduced alpha diversity. Cricket consumption increased the abundance of Faecalibacterium, whereas lentil consumption promoted Bifidobacterium. Rats fed picanha or egg exhibited the highest serum LPS concentrations, while acocil and beef induced the greatest stimulation of muscle protein synthesis followed by cricket, egg, and lentil diets. Biological effects of dietary protein depend on the entire food matrix rather than content alone and cricket and lentil matrices emerge as sustainable protein sources.