脉冲电磁场对大鼠骨髓间充质干细胞增殖及成骨分化的影响

Effects of pulsed electromagnetic fields on proliferation and differentiation of cultured rat mesenchymal stem cells

目的:探讨脉冲电磁场(PEMFs)对大鼠骨髓间充质干细胞(rMSCs)的影响.方法:用全骨髓贴壁法分离rMSCs,对其进行1Hz和15Hz的PEMFs刺激,MTT法测定细胞增殖水平,检测碱性磷酸酶活性,进行四环素荧光染色和钙结节染色.结果:rMSCs经PEMFs刺激后,各实验组细胞增殖水平均有不同程度提高,差异具有统计学意义(P<0.05),其中1Hz,0.4mT组改变最为明显(3d,0.323±0.051;5d,0.714±0.058),对照组(3d,0.246±0.044;5d,0.487±0.064),差异具有统计学意义(P<0.01);碱性磷酸酶检测实验组水平升高(5d,0.348±0.032;15d,2.339±0.034),对照组(5d,0.205±0.026;15d,0.533±0.013),差异具有统计学意义(P<0.05),四环素荧光染色和钙结节染色结果均呈阳性.结论:rMSCs经PEMFs刺激后,能促进体外培养rMSCs的增殖水平及成骨分化,磁场参数对实验结果有影响.

AIM： To study the effects of pulsed electromagnetic fields （PEMFs） on rat mesenchymal stem cells （rMSCs）. METHODS： The rMSCs were obtained by using whole marrow attachment method, and then irradiated by PEMFs of 1 Hz and 15 Hz with different intensity. The method of MTT was employed to evaluate cell proliferation; the activity of alkaline phosphatase （ALP） was measured; tetracycline fluorescence and bone nodule stainings were performed. RESULTS： After irradiation by PEMFs, the proliferation of rMSCs was accelerated （ P 〈 0.05 ） ; compared with sham group （3 d, 0.246 ± 0. 044 ; 5 d, 0.487 ± 0.064）, it changed most obviously in group of 1 Hz, 0.4 mT （3 d, 0.323±0.051; 5 d, 0.714 ±0.058） （P〈0.01）. Activity of ALP was also increased significantly （ P 〈 0.05 ）. Compared with the sham group （5 d, 0.205 ±0.026; 15 d, 0.533 ± 0.013） , the change was more obvious in group of 1 Hz, 0.4 mT （5 d, 0.348±0.032; 15 d, 2.339±0.034） （P〈0.05）. Tetracycline fluorescence staining and bone nodule staining were both positive. CONCLUSION： Irradiation of PEMFs can increase the proliferation of rMSCs and induce their differentiation into osteoblasts, which is affected by the parameters of PEMFs. In this experiment, the PEMFs of 1 Hz, 0.4 mT is most effective.