Apocynin inhibits compressive force-induced apoptosis and autophagy of periodontal ligament stem cells

ObjectiveThis study aimed to evaluate the effect of Apocynin on compressive force-induced apoptosis and autophagy in periodontal ligament stem cells (PDLSCs).Materials and MethodsPeriodontal ligament stem cells were subjected to a uniform compressive force of 2.0 g/cm2 for 24 h, without and with addition of 50, 100 and 200 mu M Apocynin. Beclin-1 was overexpressed in PDLSCs. Flow cytometry was used to assess apoptosis and transmission electron microscopy was used to evaluate ultrastructural features of PDLSCs. Immunofluorescence was used to assess the levels of microtubule-associated protein 1 light chain 3 (LC3). The protein levels of B-cell lymphoma-2 (Bcl-2), Bcl-2 associated X (Bax), Caspase-3, LC3, and Beclin were determined by Western blot analysis.ResultsCompressive force of PDLSCs significantly increased apoptosis, Bax, Caspase-3, the number of autophagosome or autolysosomes, Beclin-1, the ratio of LC3 II/LC3 I, and decreased Bcl-2. Apocynin was shown to inhibit apoptosis and Beclin-1-mediated autophagy. Over-expression of Beclin-1 increased apoptosis and autophagy.ConclusionsApplication of Apocynin attenuated long-term compressive force-induced apoptosis by regulating Beclin-1-mediated autophagy in PDLSCs. These results provide an alternative approach to improve orthodontic treatment outcomes for patients.