EDTA Enhances Stromal Cell-derived Factor 1α-induced Migration of Dental Pulp Cells by Up-regulating Chemokine Receptor 4 Expression

Introduction: In regenerative endodontics, irrigation is an important step to ensure the success of treatment. EDTA as a common irrigant has been recommended in the American Associations of Endodontists guidelines. It has been suggested that EDTA-treated dentin slices could increase the attachment, differentiation, and migration of dental pulp stem cells. However, no information is available about the effect of EDTA on the migration of dental pulp cells (DPCs). The aim of this study was to explore how EDTA affects the migration of DPCs. Methods: Cells were obtained from human premolars or third molars, and cell counting kit-8 was used to evaluate the influence of EDTA on cell proliferation at various concentrations and time points. Real-time polymerase chain reaction was used to detect the messenger RNA expression levels of transforming growth factor beta (TGF-beta) and chemokine receptor 4 (CXCR4). Protein expression was tested by the enzyme-linked immunosorbent assay and Western blot, respectively. In addition, the transwell migration assay was performed to investigate the role of EDTA pretreatment in stromal cell derived factor 1 alpha (SDF-1 alpha)-induced DPC migration. Results: Stimulation with 12% EDTA enhanced SDF-1 alpha-induced migration of DPCs. Both expressions of TGF-beta 1 and CXCR4 were increased by 12% EDTA in a time-dependent manner. After silencing CXCR4, EDTA-enhanced migration was decreased. Furthermore, the transcriptional regulation of CXCR4 by EDTA was found to be mediated by TGF-beta 1/ERK1/2 and TGF-beta 1/Smad2/3 signal pathways. Conclusions: Our results showed that 12% EDTA could promote SDF-1 alpha-induced migration of DPCs by up regulating CXCR4 expression in which TGF-beta 1 signal pathways were involved.