Osteogenic Induction Of Bone Marrow-Derived Mesenchymal Stem Cells Within Strain For Tissue Engineering

Bone marrow-derived mesenchymal stem cells (BMSCs) are a population of cells capable of replicating as undifferentiated cells and that have the potential to differentiate to lineages of mesoblastic origin. And the characters of BMSCs have suggested the great value of this specific cell population for tissue engineering. Furthermore, complex mechanical forces are clearly involved in cell development in vivo. Therefore, it is necessary to investigate the effect of strain on proliferation and differentiation of BMSCs, and may provide increased insight in the role of strain on proliferation and osteogenic differentiation of BMSCs in vitro and lead to improved strategies in bone tissue engineering.In this study, the method of cell isolation and culture was mastered, and its general biology characteristics were realized. Next, BMSCs for the following experiments were at the same third passage. Using a four-point bending loads system, a uniform 1000με cyclic tension strain was applied to the cells at 0.5Hz (1s on, 1s off) for 30 minutes per 12 hours, and lasted out 72 hours. We assessed the ALP activity of unstrained plates and strained plates at different times, the proliferation and ALP activity of BMSCs under strain and/or osteogenic supplement medium, the matrix-deposited calcium, gene expression of osteocalcin (OCN). Lastly, four kinds of materials served as bone tissue-engineering scaffold was compared.The results suggested that strained cells expressed higher ALP activity than unstrained cells, and the ALP levels expressed by BMSCs is highest at the time of the 6th hour after being applied strain. We demonstrated that BMSCs, stretched by cyclic deformation of the cell substrate, inhibited their growth and accelerated their osteogenic differentiation. And we detected that p-TCP can serve as bone tissue-engineering scaffold materials more appropriately.