Physical Stimulation-Based Osteogenesis: Effect of Secretion In Vitro on Fluid Dynamic Shear Stress of Human Alveolar...

Human alveolar bone-derived mesenchymal stem cells (hABMSCs) are promising candidates for bone therapies, which have the capacity to differentiate into osteoblasts. Recently, secretion of inducible cytokines and growth factors from mesenchymal stem cells (MSCs) has been discovered, and we also have reported the osteogenic effects of cell physical stimulation. In this study, we investigated the effects of hABMSCs-conditioned secretion media (B-CSM) on osteogenic differentiation of hABMSCs in vitro. Furthermore, we analyzed the B-CSM by proteomics array to identify inducible factors which facilitate osteogenic differentiation. To determine optimal concentration, B-CSM was firstly added at varying amounts (5, 10, 20, 40, and 60%) relative to culture medium. The viability and proliferation of hABMSCs were higher after treating with 5-20% B-CSM to the cells, compared to 40-60%. In addition, the expression of stem cells markers CD146 and STRO-1 was increased in the cells treated with 5-20% B-CSM, but decreased with 40-60%. We also found that B-CSM promoted osteogenic differentiation of hABMSCs such as mineralized nodules were strongly generated by 5-20%. B-CSM was most effective in increasing the expression of Vinculin and osteocalcin (OCN) in osteogenic differentiation of hABMSCs. Taken together, the results of our study ultimately indicate that B-CSM from hABMSCs induced by physical stimulation induce the proliferation and osteogenic differentiation of hABMSCs.