LIPUS Protects PDLSCs From Oxidative Damage and Promotes Alveolar Bone Regeneration via FOXO1.

Objective: Oxidative stress is regarded as a significant element contributing to periodontal tissue destruction and impaired regeneration. Low-intensity pulsed ultrasound (LIPUS) has been shown to effectively protect periodontal ligament stem cells (PDLSCs) from oxidative damage. However, the potential molecular mechanism of LIPUS remains unclear.

Methods: The experimental periodontitis model was established by ligation. The expression levels of oxidative stress and osteogenic markers in vivo were detected by immunohistochemistry. PDLSCs were incubated with H₂O₂ to imitate oxidative stress. A reactive oxygen species assay kit was used to determine oxidative stress status. The expression of osteogenic differentiation protein, Forkhead transcription factor-1 (FOXO1) and antioxidant protein was observed by Western blotting. SiRNA technology and the small molecule inhibitor AS1842856 were used to evaluate the role of FOXO1 in LIPUS treatment.

Results: The results demonstrated that LIPUS exerts a protective effect against oxidative damage in PDLSCs, reduces alveolar bone loss, and significantly inhibits the elevated phosphorylation levels of FOXO1 in the oxidative stress microenvironment. Moreover, the increased phosphorylation level of FOXO1 diminishes the protective effect of LIPUS.

Conclusion: Thus, these results suggest that FOXO1 may be a critical target for LIPUS to attenuate oxidative stress and regulate alveolar bone homeostasis in periodontitis.