Runx2, also known as Cbfa1, is a multifunctional transcription factor essential for osteoblast differentiation. It also plays major roles in chondrocyte maturation, mesenchymal stem cell differentiation, cleidocranial dysplasia, and the growth and metastasis of tumors. The present study was performed to investigate the functions of Runx2 in the differentiation and migration of Schwann cells and outgrowth of neurites after peripheral nervous system injury. In a model of sciatic nerve crush (SNC) injury, we found a gradual increase in the expression of Runx2, which reached a peak after 1 week. Immunofluorescence revealed increased expression of Runx2 in Schwann cells and axons after SNC injury. Runx2 and Oct-6 expression trends were consistent with each other in western blotting, and colocalization of Runx2 and Oct-6 was observed in immunofluorescence. In vitro, Runx2 promoted Schwann cell differentiation by activation of the Akt-GSK3β signaling pathway. In addition, Runx2 promoted the migration of Schwann cells and outgrowth of neurites. These findings suggest that Runx2 may be involved in neurite outgrowth and Schwann cell differentiation and migration after sciatic nerve injury.
Keywords: Crush injury; Differentiation; Neurite outgrowth; PC12; Runx2; Schwann cells; Sciatic nerve.