Effect of substrate stiffness on proliferation and differentiation of periodontal ligament stem cells.

ObjectivesThe aim of this study was to understand the effect of substrate stiffness (a mechanical factor of the extracellular matrix) on periodontal ligament stem cells (PDLSCs) and its underlying mechanism. Materials and methodsElastic substrates were fabricated by mixing 2 components, a base and curing agent in proportions of 10:1, 20:1, 30:1 or 40:1. PDLSC morphology was observed using scanning electron microscopy (SEM). Cell proliferation and differentiation were assessed after PDLSCs was cultured on various elastic substrates. Data were analysed using one-way ANOVA. ResultsSEM revealed variations in the morphology of PDLSCs cultured on elastic substrates. PDLSC proliferation increased with substrate stiffness (P<.05). Osteogenic differentiation of PDLSCs was higher on stiff substrates. Notch pathway markers were up-regulated in PDLSCs cultured on stiff substrates. ConclusionsResults suggested that the osteogenic differentiation of PDLSCs might be promoted by culturing them in a stiffness-dependent manner, which regulates the Notch pathway. This might provide a new method of enhancing osteogenesis in PDLSCs.