[Effects of mechanical stimulation on proliferation and differentiation in MG-63 osteoblast-like cells].

This paper is aimed to explore the effects of mechanical stimulation on proliferation and differentiation of osteoblasts. Cultured MG-63 osteoblast-like cells were strained by the four-point bending cell mechanics loader. In the study, we observed the effects of different magnitudes and duration of mechanical strain on the markers of proliferation and differentiation in osteoblasts. The protein levels and Alkaline phosphatase (ALP) activity were determined by western blot and alpha-nitrophenyl phosphate assay respectively. The mineralization nodules were stained using Alizarin Red-S method. We found: (1) the expression of proliferating cell nuclear antigen (PCNA), ALP activity in strained group were significantly increased compared to those in the control group, but the role did not increase with the increase of the magnitude of the stimulation; and (2) under appropriate stimulation (2000 microstrain), the expression of PCNA, COL I protein and ALP activity increased gradually with the increase of loading time, and appropriate stimulation promoted the formation of mineralization nodules. It indicated that appropriate mechanical stimulation could promote proliferation and differentiation of osteoblasts.