Lactiplantibacillus plantarum -Fermented Broccoli Attenuates Metabolic Dysfunction and Improves Skeletal Muscle Quality in High-Fat/High-Fructose Diet-Fed Mice

Abstract Muscle loss accompanied by excessive adiposity is a critical component of metabolic dysfunction. This study investigated the effects of Lactiplantibacillus plantarum-fermented broccoli (FHB) in high-fat/high-fructose diet (HFFD)-fed C57BL/6J mice. LC–MS profiling showed that fermentation generated metabolites, including 2-hydroxycaproic acid, 3-phenyllactic acid, and a tetrahydro-β-carboline derivative. FHB supplementation attenuated visceral adiposity, hepatic steatosis, and insulin resistance while preserving grip strength. In the gastrocnemius muscle, FHB was associated with higher phosphorylation of the IRS1/PI3K/Akt and mTOR/p70S6K/4E-BP1 pathways and with lower expression of the ubiquitin ligases Atrogin-1 and MuRF-1. 16S rRNA sequencing showed altered gut microbiota, with enrichment of the butyrate-producing species Anaerostipes hominis and Bifidobacterium pseudolongum in the FHB group. These findings indicate that FHB supplementation was associated with attenuated metabolic dysfunction and preserved muscle function, accompanied by fermentation-derived metabolites and gut microbiota remodeling.