Spatial Transcriptomics Reveals Tgfβ1–Orchestrated Periodontium Stem Cell Senescence

This study investigates the role of TGF-β1 in periodontal ligament stem cell (PDLSC) senescence and elucidates the underlying molecular mechanisms, enhancing our current understanding of age-related periodontal diseases. An integrative multi-omics approach was used. Spatial transcriptomics was applied to murine jawbone tissues to analyze Tgfb1 mRNA expression in the periodontium, with pseudotime analysis to evaluate its dynamic pattern. Human PDLSCs were used as a model to investigate the effects of TGF-β1 signaling, with assays conducted to examine DNA methylation, senescence phenotypes, cell cycle arrest, and associated pathways. Spatial transcriptomic profiling revealed Tgfb1 enrichment in the periodontium with an upregulated tendency. In human PDLSCs, TGF-β1 induced a senescent phenotype marked by G2 phase cell cycle arrest. Mechanistically, TGF-β1 triggered reactive oxygen species (ROS) accumulation via DNA methylation-mediated repression of PRKAG2, encoding AMPKγ2, leading to DNA damage and ATM signaling activation. Pharmacological inhibition of ROS with N-acetyl-l-cysteine (NAC) or reversal of PRKAG2 epigenetic silencing with decitabine mitigated PDLSC senescence by inhibiting ATM signaling. Our findings provide the first spatially resolved transcriptomic map of murine jawbone tissues and identify DNA methylation as a critical regulator of TGF-β1-induced PDLSC senescence. These insights pave the way for developing stem cell-based therapies to combat age-related periodontal diseases and improve both oral and systemic health.