[Response to dynamic strain in human periosteal cells grown in vitro]

The objective of this program is to investigate the biological effect of dynamic strain on human periosteal cells in vitro. Using a well-established model, the Flexercell unit, we placed mechanical stress (50,000 microstrain, 1 Hz and sine wave) on human periosteal cells grown in collagen coated flexible membrane. The time points of proliferative and differentiative properties were assessed by means of cell counting, thymidine incorporation, synthesis of alkaline phosphatase and osteocalcin, and long term of mechanical load induced calcium nodules formation was also demonstrated. The results showed that the application of highly controlled strains exerted a significant effect on human periosteal cells by up regulation of osteogenic properties rather than exercised an influence on proliferation. The results suggested that the promoting effects of dynamic strain on human periosteal cells probably contribute to the biological function of mechanical loading bearing.