Exploring the relationship between gut microbiota-metabolite axis and Jiawei Danxuan Koukang's therapeutic effects in male rats with oral submucous fibrosis: A multi-omics analysis.

Abstract

OBJECTIVE: This work aims to explore how Jiawei Danxuan Koukang (JDK) ameliorates Oral Submucous Fibrosis (OSF) via regulating the gut microbiota and its metabolites. DESIGN: We established an OSF rat model via oral mucosal arecoline injection. Rats were randomly divided into five groups: control, model, lycopene-treated, quercetin-treated, and JDK-treated. After intervention, we analyzed: serum metabolites by Liquid Chromatography-Mass Spectrometry -based untargeted metabolomics; gut microbiota profiling via 16S rDNA sequencing; oral mucosal histopathology and fibrosis using hematoxylin-eosin and Masson trichrome staining; expressions of fibrosis-related proteins (Transforming Growth Factor-β1 (TGF-β1), Collagen Type I Alpha 1 Chain (COL1A1)) by western blot; and cytokines (Interleukin-1β, Interleukin-6, Interleukin-10) in serum, oral and colon tissues via enzyme-linked immunosorbent assay. RESULTS: In the OSF model group, 120 serum metabolites were upregulated and 39 were down-regulated. When comparing the JDK group with the model group, 83 metabolites were upregulated and 132 were downregulated in the JDK group. Specifically, JDK targeted key metabolites: prostaglandins, leukotrienes, lysophosphatidylcholine, and 4-hydroxyproline. JDK also regulated two critical metabolic pathways: gly-cine-serine-threonine metabolism and tryptophan metabolism. JDK reduces the pro-inflammatory Ruminococcus and restores the butyrate-producing Lachnospiraceae_NK4A136_group. JDK downregulated Interleukin-1β and Interleukin-6 levels systemically and locally, concurrently increasing Interleukin-10, and reduced the expression of fibrosis-related proteins (TGF-β1, COL1A1) in the oral mucosa. CONCLUSIONS: JDK alleviates OSF by normalizing inflammation and fibrosis-related metabolic pathways, linking gut microbiota remodeling to metabolic homeostasis.