Effects of electromagnetic field activated-ERK signaling pathway on proliferation and osteogenic differentiation of rat bone marrow mesenchymal stem cells / 中国组织工程研究

ABSTRACT

BACKGROUND: It has been demonstrated that electromagnetic field (EMF) can adjust proliferation and differentiation of bone marrow mesenchymal stem cells, but the specific mechanism is not clear. OBJECTIVE: To investigate the effects of EMF-activated ERK1/2 pathway on proliferation and osteogenic differentiation of rat bone marrow mesenchymal stem cells.METHODS: The 3rd passage of rat bone marrow mesenchymal stem cells were received EMF treatment (15 Hz, 1 mT, sine wave), 20 μmol/L PD98059 + EMF treatment, or only PD98059 treatment. Simultaneously, a normal control group was established. Western blotting was applied to detect the activation of ERK signal pathway after EMF exposure. MTT assay was used to determine the activation of proliferation of cells. And alkaline phosphatase (ALP) activity in cells was detected by an ALP kit. RESULTS AND CONCLUSION: The ERK1/2 phosphorylation, proliferation and ALP activity of rat bone marrow mesenchymal stem cells were remarkably increased after exposure to EMF (P < 0.01). PD98059 could effectively block the increasing of ERK1/2 phosphorylation and cell proliferation (P < 0.01), but elevate ALP activity in a certain level (P < 0.01). EMF stimulation can fast activate ERK1/2 signal pathway and then promote the proliferation of rat bone marrow mesenchymal stem cells, however, ERK1/2 signal pathway activation has a less effect on osteogenic differentiation of bone marrow mesenchymal stem cells.