Optimal parameters for the enhancement of human osteoblast-like cell proliferation in vitro via shear stress induced by high-frequency mechanical vibration

Introduction: Biomechanical stimulation of cultured human osteoblast-like cells, which is based on controlled mechanical vibration, has been previously indicated, but the exact parameters that are effective for cells' proliferation enhancement still elusive due to lack direct data recordings from stimulated cells in culture. Therefore, we developed a low friction tunable system enables recording narrow range parameters, above infrasonic spectrum, applied uniformly monolayer culture, aiming identify enhance osteoblast vitro. Methods: Human explant culture samples were exposed vibration 10-70Hz frequencies two minutes, four 24 hours intervals. Cell numbers cellular alkaline phosphatase activity (a marker cell maturation), and lactate dehydrogenase media (representing death) measured after protocol application compared statistically control cultures kept static conditions. The was deduced number death measurements. Results: We found 50-70 Hz frequency (10-30 μm maximal displacement amplitude, 0.03g peak-to-peak acceleration) optimal enhancing proliferation(p<0.05), with parallel decrease their maturation (p<0.01). Discussion: detected excitation induction vitro by platform, can be used as standardized method research mechanotransduction osteoblast.