Panax Notoginseng Saponins Regulate Autophagy to Ameliorate Oral Submucous Fibrosis

Objectives This study aimed to explore the correlation between autophagy and oral submucous fibrosis (OSF), investigate the therapeutic effects of Panax notoginseng saponins (PNS) on OSF in vitro and in vivo, verify expression changes of autophagy-related factors following PNS intervention, and elucidate the underlying mechanism by which PNS modulates autophagy. Methods Histopathological alterations were assessed using haematoxylin-eosin (HE) and Masson trichrome staining. Autophagy was evaluated by immunohistochemistry (IHC), transmission electron microscopy (TEM), and RT-qPCR. Collagen I and autophagy-related markers were measured by Western blotting and immunofluorescence (IF). Results OSF tissues exhibited epithelial atrophy, collagen fiber deposition, and inflammatory infiltration, accompanied by upregulated collagen I and p62 expression, as well as downregulated light chain 3 (LC3) and LC3-II expression, and decreased autophagosome formation. PNS treatment reduced collagen accumulation, inflammation, and muscular atrophy, while restoring epithelial thickness. In arecoline (ARE)-treated HaCaT cells, PNS reversed the abnormal expression of collagen I and LC3-II. Conclusions Dysregulated expression of autophagy-related factors is closely associated with OSF pathogenesis. PNS ameliorates OSF by modulating autophagy, providing a novel therapeutic mechanism for this potentially malignant disorder.