Proteomics Insights Into Gingival Aging: The Role of Oxidative Stress and Key Signaling Pathways

Gingival aging is closely associated with oxidative stress, yet its molecular mechanisms remain poorly understood. This study employed proteomic analysis of gingival tissues from young and aged mice, combined with functional experiments, to elucidate the central role of oxidative stress in gingival aging and its underlying mechanisms.

Proteins differentially expressed in old mice compared to young mice were screened using a 4D label-free mass spectrometry platform. The differentially expressed proteins were then subjected to bioinformatics analyses, including Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Set Enrichment Analysis (GSEA), and Protein-Protein Interaction Networks (PPI). At the same time, H₂O₂ was used to stimulate human periodontal ligament fibroblasts to induce an aging model. Combined with H&E staining, immunohistochemistry, Western blot, SOD activity detection, and other experiments, the relationship between oxidative stress and gingival aging was comprehensively evaluated across.

The level of reactive oxygen species (ROS) in gingival tissue of aged mice was significantly increased, accompanied by decreased expression of epidermal growth factor receptor (EGFR) and inhibition of the PI3K-AKT signaling pathway. Proteomic analysis identified 224 differentially expressed proteins, of which up-regulated proteins were related to redox function, while down-regulated proteins were involved in cell proliferation and tissue repair. Further experiments showed that inhibition of cytochrome P450 (CYP450) reduced ROS levels and alleviated aging-related phenotypes. In addition, the functional inhibition of EGFR aggravated the decrease in the activity of gingival fibroblasts, and the antioxidant 1-aminobenzotriazole (ABT) pretreatment could partially reverse this effect.

Our findings indicate that oxidative stress drives gingival functional decline and tissue aging by disrupting EGFR-mediated signaling pathways and amplifying CYP450 activity. This study provides novel insights into the molecular mechanisms of gingival aging and highlights the potential of targeting oxidative stress and EGFR signaling as anti-aging therapeutic strategies.