Activation of multiple signaling pathways during the differentiation of mesenchymal stem cells cultured in a silicon nanowire microenvironment

Mesenchymal stem cells (MSC) offer an optimal source for bone tissue engineering due to their capability of undergoing multilineage differentiation, where the mechanical properties of the microenvironment of MSCs are vital for osteochondral formation. However, the mechanisms of how mechanical and microenvironmental cues control osteogenesis and chondrogenesis are yet to be elucidated. In this study, we investigated the effects of vertically aligned silicon nanowire (SiNW) array on the differentiation of MSCs and the associated molecular mechanisms involved in osteogenesis and chandrogenesis. The results showed that the microenvironment of SiNW array activated a number of mechanosensitive pathways (including Integrin, TGF-beta/BMP, Akt, MAPK, Insulin, and Wnt pathways) in MSCs, which converged to stimulate the osteogenesis and chondrogenesis via the Ras-Raf-MEK-ERK cascade. From the Clinical Editor: This study reports on the mechanisms and microenvironmental influence of osteogenesis and chondrogenesis by mesenchymal stem cells interacting with vertically aligned silicon nanowire scaffolds. (C) 2014 Elsevier Inc. All rights reserved.