Dnmti@Zif-8 Enhances Biomimetic Pulp Regeneration Via Epigenetic Regulation

This study aimed to develop a biomimetic therapy integrating DNMTi@ZIF-8 with DPSC spheroids to effectively regenerate the dentin-pulp complex. Dynamic DNA methylation profiles during mouse tooth germ development was evaluated through 5mC expression level. DNMTi@ZIF-8 nanoplatform was synthesized in-situ by encapsulating DNMTi within ZIF-8 nanoplatforms. The effects of DNMTi and DNMTi@ZIF-8 on angiogenesis was evaluated in vitro and in vivo using scratch assays, tube formation assays, the chicken embryo chorioallantoic membrane test and angiogenic gene expression; The effects of DNMTi@ZIF-8 on odontogenic differentiation of DPSC spheroids was investigated through ALP and Alizarin red staining and odontogenic gene expression. In vivo confirmation was performed in a semi-orthotopic pulp regeneration model in nude mice. During mouse tooth germ development, a progressive reduction in 5mC content was observed, suggesting its role in dentinogenesis. In vitro, DNMTi promoted odontogenic differentiation of DPSCs but inhibited angiogenesis. DNMTi@ZIF-8 extended the activity of DNMTi and promoted angiogenesis by activating the PI3K-AKT signaling. DPSC spheroids exhibited enhanced odontogenic differentiation compared to monolayer cells. In vivo, the combined therapy of DPSC spheroids and DNMTi@ZIF-8 significantly promoted dentin-pulp complex regeneration, as evidenced by increased dentin-like tissue formation and vascularization. This study demonstrates the efficacy of the biomimetic regenerative approach that integrates epigenetic modulation via DNMTi@ZIF-8 with stem cell spheroid culture for dentin-pulp complex regeneration.