Dentin-derived Inorganic Minerals Promote the Osteogenesis of Bone Marrow-derived Mesenchymal Stem Cells: Potential Applications for Bone Regeneration
Abstract Background Oral and maxillofacial bone loss is highly prevalent among populations and nowadays increased attention has been focused on dentin derivatives as desirable graft materials for bone regeneration. In this study, dentin-derived inorganic minerals (DIM) were fabricated with a high-temperature calcination technique and the effects of DIM on the osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMMSCs) and the bone formation were elucidated.Methods The effects of DIM on BMMSCs proliferation, apoptosis capacity were evaluated by CCK-8, flow cytometry and EdU assays. Alkaline phosphatase (ALP) activity detection, ALP staining, alizarin red staining and osteogenic markers expression analysis were performed to investigate the influence of DIM on the osteogenic differentiation of BMMSCs, as well as the relevant signal mechanisms. The model of critical-sized defects in calvarium of rats was constructed for exploring the in vivo efficiency of DIM on bone regeneration.Results Cell viability assays indicated that DIM had no cytotoxicity. BMMSCs cultured with DIM presented a higher level of osteogenic differentiation ability than those in the control group. The activation in ERK and p38 signals was detected in DIM-treated BMMSCs, and both pathways and osteogenic process were suppressed while using ERK inhibitor U0126 and p38 inhibitor SB203580, respectively. Furthermore, the animal experiments revealed that DIM could dramatically enhance new bone formation compared to the control group.Conclusion All these results demonstrated that DIM could promote BMMSCs osteogenic differentiation via triggering ERK and p38 MAPK signaling pathways and be a novel predictable material for facilitating bone formation.