The transcription factor cyclic adenosine 3′,5′-monophosphate response element-binding protein enhances the odonto/osteogenic differentiation of stem cells from the apical papilla

Aim To investigate the role of cAMP response element-binding protein (CREB) in the regulation of odonto/osteogenic differentiation of stem cells from the apical papilla (SCAPs). Methodology Stem cells from the apical papilla were obtained from human impacted third molars ( n = 15). Isolated SCAPs were transfected with CREB overexpressing/silenced lentivirus. Transfected cells were stained with alizarin red to investigate mineralized nodule formation. The expression of the mineralization-related genes, alkaline phosphatase (ALP), collagen type I (Col I), runt-related transcription factor 2 (RUNX2), osterix (OSX) and osteocalcin (OCN), was determined by quantitative reverse transcription polymerase chain reaction (qRT-PCR). Protein expression of the odontogenic-related marker dentine sialoprotein (DSP) and the osteogenic-related marker RUNX2 was measured by Western blotting analysis. One-way analysis of variance ( anova ) and Student's t -test were used for statistical analysis ( a = 0.05). Results The overexpression of CREB enhanced mineralized nodule formation and up-regulated ( P < 0.05) the mRNA levels of odonto/osteogenic-related markers, including ALP, Col I, RUNX2, OSX and OCN, and also increased ( P < 0.05) the protein expression of DSP and RUNX2. In contrast, the silencing of CREB inhibited ( P < 0.05) the mineralization capacity of the SCAPs and decreased ( P < 0.05) the expression of odonto/osteogenic-related markers. Conclusion Up-regulation of CREB expression promoted odonto/osteogenic differentiation of SCAPs and provided a potential method for the regeneration of the dentine–pulp complex.