Research Article Mechanical Stress Stimulates the Osteo/Odontoblastic Differentiation of Human Stem Cells from Apical Papilla via

Copyright © 2014 Chao Mu et al.This is an open access article distributed under the Creative CommonsAttribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Background Information. Stem cells from apical papilla (SCAPs) are a potent candidate for the apexogenesis/apexification due to their multiple differentiation capacity. During the orthodontic treatment of developing teeth, SCAPs in vivo are usually subjected to the cyclic stress induced by compression forces. However, it remains unclear whether mechanical stress can affect the proliferation and differentiation of human SCAPs. Results. Human SCAPs were isolated and stimulated by 200 g mechanical stimuli for 30min and their proliferation and differentiation capacity were evaluated in vitro at different time points. MTT and FCM results demonstrated that cell proliferation was enhanced, while TEM findings showed the morphological and ultrastructural changes in stress-treated SCAPs. ALP activity and mineralization capacity of stress-treated SCAPs were upregulated. In the meantime, higher odontogenic and osteogenic differentiation were found in stress-treated SCAPs by real-time RT-PCR andWestern blot, as indicated by the expression of relatedmarkers at bothmRNA and protein levels.Moreover, the protein expressions of pJNK and pERKMAPK pathways were upregulated. Conclusion. Together, these findings suggest that mechanical stress is an important factor affecting th