静磁场对骨髓间充质干细胞增殖及骨向分化的影响

目的研究0.25 T、0.35 T、0.42 T 静磁场持续或间歇曝磁对骨髓间充质干细胞(MSCs)增殖及骨向分化的影响。方法全骨髓贴壁筛选法分离MSCs，取第三代MSCs采用强度分别为0.25 T、0.35 T、0.42 T静磁场持续曝磁或间歇曝磁，CCK-8 法检测各组细胞增殖活力，并观察0.35 T连续曝磁后MSCs碱性磷酸酶活性、骨钙素含量。结果细胞经过磁场处理后，与对照组相比，细胞增殖活力均降低，连续曝磁第7 天效果最为显著(P<0.001)，而0.25 T、0.35 T间歇曝磁第2~8 天持续表现出显著抑制效应(P<0.001)。0.35 T持续曝磁后，MSCs碱性磷酸酶活性和骨钙素水平均增高(P<0.05)。结论0.25 T、0.35 T、0.42 T静磁场连续曝磁或间歇曝磁均可抑制MSCs增殖，0.35 T连续曝磁能促进MSCs向成骨细胞方向分化。

Effects of Static Magnetic Field on Proliferation and Osteogenic Differentiation of Mesenchymal Stem Cells

Objective To investigate the effect of exposure to 0.25 T, 0.35 T, 0.42 T static magnetic fields (SMF) on the proliferation and osteogenic differentiation of mesenchymal stem cells (MSCs). Methods Primary bone marrow MSCs were obtained from Sprague-Dawley rats and screened by adhesive method. MSCs were exposed to 0.25 T, 0.35 T, 0.42 T SMF continuously and 24 h intermittently respectively.The cell proliferation activity was detected by Cell Counting Kit (CCK-8) assay. The osteogenic differentiation markers including alkaline phosphatase (ALP) activity and osteocalcin were analyzed after continuously exposure to 0.35 T SMF. Results Compared with the control group, the proliferation activity of SMF-treated cells significantly decreased, especially on the 7th day (P<0.001) after continuous exposure,and on the 2nd to 8th day in 0.25 T, 0.35 T SMF intermittent exposure groups (P<0.001). Both the alkaline phosphatase activity and the level of osteocalcin significantly increased in MSCs after continuous exposure to 0.35 T SMF (P<0.05). Conclusion Continuous or intermittent exposure to 0.25 T, 0.35 T and 0.42 T SMF could effectively inhibit the proliferation of MSCs. Continuous exposure to 0.35 T SMF could enhance the osteogenic differentiation of MSCs.