Remodeling of Gut Microbiota Metabolic Function Is Associated with the Therapeutic Effects of Wenweishu Capsules in Chronic Gastritis

Chronic gastritis (CG) is linked to gut–gastric axis dysbiosis. Wenweishu Capsules (WWS) are clinically used to treat CG, but their concurrent regulatory effects on this axis remain unclear. A CG rat model was established using sodium deoxycholate, ammonia, ethanol, and irregular feeding. Rats received WWS (0.38 g·kg−1·d−1) for 4 weeks. Gastric lesions, inflammation, and gut microbiota were evaluated via histopathology, ELISA, 16S rRNA sequencing, PICRUSt prediction, and correlation analysis. WWS improved general condition, food intake, and weight gain in CG rats, alleviated gastric mucosal damage, and reduced serum TNF-α and IL-6. These effects were associated with altered IκBα expression and NF-κB pathway modulation. WWS reversed gut microbiota dysbiosis, restored α- and β-diversity, increased Lachnospiraceae NK4A136 group abundance, and suppressed potential pathogens. Functional prediction showed that WWS upregulated beneficial pathways such as carbohydrate metabolism and downregulated infection-related pathways. Correlation analysis linked TNF-α/IL-6 negatively with the Lachnospiraceae NK4A136 group and positively with Bacteroides. WWS ameliorates CG through a multi-dimensional mechanism that may involve modulation of the NF-κB inflammatory axis, rebalancing of gut microbiota structure, and remodeling of microbial metabolic function. These findings provide preliminary evidence for a potential microbe–drug interaction strategy for CG, though causal relationships require further mechanistic validation.