The mechanism of honeysuckle peptides in ameliorating hyperuricemia in mice via the PGC-1α/PPARγ/ABCG2 pathway

Ethnopharmacological relevance Lonicera japonica Thunb (honeysuckle), a traditional Chinese medicine, has been historically used to clear heat, detoxify, and dispel wind-heat. Modern research has identified various bioactive constituents from honeysuckle, supporting its potential in managing inflammatory and metabolic disorders. However, the anti-hyperuricemic activity and mechanism of its peptide components remain unexplored. Aim of the study: This study aimed to investigate the anti-hyperuricemic effect of honeysuckle-derived peptides and the underlying mechanisms, with a focus on uric acid production, excretion, and gut microbiota modulation. Materials and methods Nine novel peptides were identified from honeysuckle by HPLC-MS/MS and screened through molecular docking against xanthine oxidase (XOD). In vitro XOD inhibition and antioxidant assays were performed. A hyperuricemic mouse model was induced by potassium oxonate and hypoxanthine. Mice were treated with honeysuckle peptides at low, medium, and high doses. Serum biomarkers, renal and ileal histopathology, protein and mRNA expression of PGC-1α/PPARγ/ABCG2 pathway components, and gut microbiota composition (16S rRNA sequencing) were analyzed. Results Molecular docking confirmed strong binding between the peptides and XOD. In vitro , honeysuckle peptides significantly inhibited XOD activity and exhibited potent antioxidant capacity. In vivo , peptide treatment effectively reduced serum uric acid, XOD, creatinine, and blood urea nitrogen levels, alleviated renal and intestinal tissue damage, and suppressed inflammatory cytokines. The treatment also significantly upregulated the renal PGC-1α/PPARγ/ABCG2 pathway at both protein and mRNA levels. Furthermore, the peptides restored gut microbial diversity and corrected the Firmicutes/Bacteroidota ratio. Conclusion Honeysuckle peptides ameliorate hyperuricemia through a dual mechanism: inhibiting uric acid production by suppressing XOD activity and promoting its renal excretion by activating the PGC-1α/PPARγ/ABCG2 pathway, coupled with restoring gut microbiota homeostasis. This study provides a pharmacological basis for the traditional use of honeysuckle and highlights its peptides as promising candidates for managing hyperuricemia.