Fucoidan alleviates kidney fibrosis by shaping the gut microbiota and modulating tryptophan metabolism

) for 14 days. Kidney metabolomics and 16S rRNA sequencing of the gut microbiota were performed. As a result, UUO induced pronounced disturbances in tryptophan metabolism and marked gut microbial dysbiosis. FPS treatment attenuated renal fibrosis, normalized key tryptophan pathway intermediates and related metabolic enzymes in the kidneys, and partially restored the gut microbial composition. These results implicate the modulation of tryptophan metabolism and the gut microbiota in the anti-fibrotic effects of FPS, supporting its potential as a natural therapeutic candidate for renal fibrosis and CKD.