Stiffness regulates the proliferation and osteogenic/odontogenic differentiation of human dental pulp stem cells via the WNT signalling pathway

Abstract Objectives Researches showed that stiffness of the extracellular matrix can affect the differentiation of many stem cells. Dental pulp stem cells ( DPSC s) are a promising type of adult stem cell. However, we know little about whether and how the behaviour of DPSC s is influenced by stiffness. Materials and methods We carried out a study that cultured DPSC s on tunable elasticity polydimethylsiloxane substrates to investigate the influence on morphology, proliferation, osteogenic/odontogenic differentiation and its possible mechanism. Results Soft substrates changed the cell morphology and inhibited the proliferation of DPSC s. Expression of markers related to osteogenic/odontogenic differentiation was significantly increased as the substrate stiffness increased, including ALP (alkaline phosphatase), OCN (osteocalcin), OPN (osteopontin), RUNX ‐2 (runt‐related transcription factor‐2), BMP ‐2 (bone morphogenetic protein‐2), DSPP (dentin sialophosphoprotein) and DMP ‐1 (dentin matrix protein‐1). Mechanical properties promote the function of DPSC s related to the Wnt signalling pathway. Conclusions Our results showed that mechanical factors can regulate the proliferation and differentiation of DPSC s via the WNT signalling pathway. This provides theoretical basis to optimize dental or bone tissue regeneration through increasing stiffness of extracelluar matrix.