Abstract
Periodontitis is an inflammation of the alveolar bone and soft tissue surrounding the teeth. Although mesenchymal stem cells (MSCs) have been implicated in periodontal regeneration, the mechanisms by which they promote osteogenesis remain unclear. We examined whether epigenetic modifications mediated by the long-noncoding RNA (lncRNA) NR_045147, which plays a crucial role in cancer, influence the osteogenic differentiation of periodontal ligament stem cells (PDLSCs). Alkaline phosphatase staining, alizarin red staining, and western blotting were used to detect the effects of NR_045147 on PDLSC osteogenic differentiation. Scratch migration and transwell chemotaxis assays were used to evaluate the effects of NR_045147 on PDLSC migration. Mitochondrial function was evaluated via Seahorse XF analysis to measure changes in cellular respiration upon manipulation of NR_045147 expression. Ubiquitination assays were performed to examine the protein stability and degradation pathways affected by the NR_045147-MDM2 interaction. An in vivo nude rat calvarial defect model was established and gene-edited PDLSCs were re-implanted to examine the osteogenic effects of NR_045147. NR_045147 significantly reduced PDLSC osteogenic differentiation and migration ability both in vitro and in vivo. Under inflammatory conditions, the loss of NR_045147 rescued osteogenesis. NR_045147 significantly blocked the expression of integrin beta3-binding protein (ITGB3BP). Mechanistically, NR_045147 promoted the ITGB3BP-MDM2 interaction, thus increasing ITGB3BP ubiquitination and degradation. NR_045147 regulated PDLSC mitochondrial respiration and ITGB3BP upregulation efficiently promoted their osteogenic differentiation and migration ability. Concluding, NR_045147 downregulation enhances PDLSC osteogenic differentiation and migration, connects changes in cellular metabolism to functional outcomes via mitochondrial respiration, and promotes ITGB3BP degradation by mediating its interaction with MDM2.