Quercetin Attenuates Vocal Fold Fibrosis via PI3K/AKT and MAPK Pathways: An Integrative Network Pharmacology and Experimental Study.

Objective

This study combined network pharmacology with in vivo and in vitro experiments to investigate the molecular mechanisms of quercetin against vocal fold fibrosis (VFI).

Methods

Common targets of quercetin and VFI were identified via network pharmacology. A protein-protein interaction network was constructed, and key pathways were analyzed. Molecular docking was performed to evaluate binding affinity between quercetin and core targets. A rat model of vocal fold scar (in vivo) and TGF-β1-stimulated vocal fold fibroblasts (in vitro) were used to assess the expression of PI3K/AKT and MAPK pathway proteins, as well as changes in cell proliferation, migration, and apoptosis.

Results

A total of 92 common targets were identified, with significant enrichment in the PI3K/AKT and MAPK pathways. Molecular docking showed binding energies < -5 kcal/mol for quercetin with PI3K, AKT1, and p38. In vivo, quercetin significantly inhibited the expression of PI3K, AKT, and p38 (P < 0.05). Moreover, quercetin and the PI3K inhibitor Alpelisib both significantly improved extracellular matrix organization, as evidenced by increased Energy, Correlation, and Homogeneity, and decreased Entropy and Contrast in gray-level co-occurrence matrix analysis (P < 0.05). Both treatments also restored hyaluronic acid and elastic fiber content in scarred vocal folds (P < 0.05). In vitro, quercetin suppressed the proliferation and migration of vocal fold fibroblasts (P < 0.05) and promoted apoptosis (P < 0.05).

Conclusion

Quercetin exerts anti-fibrotic effects on vocal folds by multi-target inhibition of PI3K/AKT and MAPK signaling pathways, thereby modulating fibroblast behavior, preserving extracellular matrix integrity, and restoring key matrix components such as hyaluronic acid and elastic fibers.