Conclusions
SDF-1/EX-4 cotherapy synergistically regulated PDLSC activities, promoted periodontal bone formation, thereby providing a new strategy for periodontal bone regeneration.
Methods
Cell-counting kit-8 (CCK8), transwell assay, qRT-PCR and western blot were used to determine the effects and mechanism of SDF-1/EX-4 cotherapy on PDLSCs in vitro. A rat periodontal bone defect model was developed to evaluate the effects of topical application of SDF-1 and systemic injection of EX-4 on endogenous cell recruitment, osteoclastogenesis and bone regeneration in vivo.
Results
SDF-1/EX-4 cotherapy had additive effects on PDLSC proliferation, migration, alkaline phosphatase (ALP) activity, mineral deposition and osteogenesis-related gene expression compared to SDF-1 or EX-4 in vitro. Pretreatment with ERK inhibitor U0126 blocked SDF-1/EX-4 cotherapy induced ERK signal activation and PDLSC proliferation. SDF-1/EX-4 cotherapy significantly promoted new bone formation, recruited more CXCR4+ cells and CD90+ /CD34- stromal cells to the defects, enhanced early-stage osteoclastogenesis and osteogenesis-related markers expression in regenerated bone compared to control, SDF-1 or EX-4 in vivo. Conclusions: SDF-1/EX-4 cotherapy synergistically regulated PDLSC activities, promoted periodontal bone formation, thereby providing a new strategy for periodontal bone regeneration.