Contact Co-culture of Osteoblasts and Sympathetic Neuronal Cells Promotes Differentiation of Both Cell Types

Background/Aim: Bone and nerve reconstruction is crucial for treating various diseases of the oral and maxillofacial region. However, the relationship between bone and nervous system has not yet been fully elucidated. Therefore, we aimed to examine the interaction between osteoblasts and neuronal cells in contact co-culture. Material and Methods: Osteoblasts and sympathetic neuronal cells were grown in contact co-culture. Microscopic observation, a mineralization assay, immunofluorescence staining, and DNA microarray analysis were performed. Results: Microscopic observation revealed morphological changes in the osteoblasts that were co-cultured with sympathetic neuronal cells. Contact co-culture enhanced osteoblast calcification and upregulated a neuronal marker. Not only osteoblast differentiation signals, but also neuronal signals were increased in murine osteoblasts that were co-cultured with rat sympathetic neuronal cells. We also found that not only rat neuron differentiation signals, but also osteoblast differentiation signals were increased in rat sympathetic neuronal cells that were co-cultured with murine osteoblasts. Conclusion: In the contact co-culture with osteoblasts and sympathetic neuronal cells, the sympathetic neuronal cells promoted osteoblast differentiation, and the osteoblasts promoted neuron differentiation.