Metaproteomic characterization of host–microbiome dynamics induced by Triphala extract in an obese ascending colon model

Triphala has been linked to modulation of gut microbiota and short-chain fatty acid (SCFA) production. Yet, the proteomic mechanisms underlying host–microbiome responses remain poorly understood. A dynamic in vitro ascending colon model inoculated with fecal microbiota from an obese adult donor was used to evaluate the impact of daily Triphala extract (2 g) over four weeks, followed by a two-week post-treatment phase. Weekly samples were analyzed using high-resolution shotgun metaproteomics to profile microbial- and host-derived proteins. Principal component and differential expression analyses revealed rapid proteomic remodeling during supplementation, with rebound patterns after withdrawal. Microbial proteomes showed modulation of amino acid, carbohydrate, and nucleotide metabolism, alongside transient induction of translation, transport, and vitamin-related pathways. Stress-associated proteins reappeared in the post-treatment phase, indicating microbial resilience. In contrast, host proteomes exhibited extensive shifts, with transcriptional regulation dominating gene ontology enrichment. Lipid metabolism regulators, including DGAT1/2 and RGS14, were among the most variable proteins. Correlation analysis highlighted cross-talk, with microbial metabolic enzymes positively associated with host transcriptional regulators, and bacterial stress proteins negatively associated with host structural proteins. This time-resolved metaproteomic study demonstrates that Triphala extract induces dynamic yet reversible remodeling of both microbial and host proteomes in an obese colon model. By stimulating microbial metabolism and reprogramming host transcriptional pathways, Triphala extract shows potential as a dietary modulator of obesity-associated gut dysbiosis, while underscoring the value of metaproteomics in precision nutrition research. • Longitudinal metaproteomics revealed host–microbiome remodeling. • Triphala modulated microbial metabolism and stress response pathways. • Host proteomes showed shifts in transcriptional and lipid regulation. • Cross-talk links microbial enzymes with host regulatory proteins.