中文摘要：

目的：研究不同浓度镁离子对成骨细胞活力和分化的影响,并探讨镁基生物材料促进骨再生的机制。方法：分离培养大鼠乳鼠颅骨成骨细胞,之后将细胞分别在DMEM培养基（含有0.8 m M镁离子;对照组）和含有6 m M、10 m M、18 m M镁离子（实验组）的培养基中进行培养,通过MTT法测定细胞活力,ALP活力、茜素红染色法测定成骨细胞的分化,通过western blot法测定不同浓度镁离子组中PI3K/Akt信号通路的表达情况。结果：6 m M、10 m M镁离子组成骨细胞活力、ALP活力、基质矿化水平较对照组明显增加（P〈0.05）,18 m M镁离子组成骨细胞活力、ALP活力、基质矿化水平对照组明显降低（P〈0.05）。在10 m M镁离子组加入wortmannin后,上述增强的结果受到抑制。结论：6-10 m M镁离子促进成骨细胞的活力和分化,而过高浓度镁离子（18 m M）对成骨细胞的活力和分化具有抑制作用。10 m M镁离子通过激活PI3K/Akt信号通路促进成骨细胞的活力和分化。这项研究为医用镁基生物材料的进一步研究提供了很好的参考作用。

英文摘要：

Objective： To investigate the effect of different Mg2＋ concentrations on viability and differentiation of osteoblasts and the underlying mechanism. Methods： Osteoblasts were isolated and extracted from the calvarial bone of 1-day old Sprague-Dawley Rats. Subsequently, cells were cultured with DMEM （0.8 mM Mg2＋, control group） and culture medium containing 6, 10 and 18 mM concentrations of Mg2＋ （treatment group）, respectively. The viability of osteoblasts was measured by MTT assay. The osteogenic differentiation of osteoblasts was measured by ALP activity and Alizarin red staining. Western blot was used to determine the activation of PI3K/Akt signaling pathway in different Mg：＋ concentrations. Results： The groups cultured with 6 and 10 mM Mg：＋ showed enhanced cell viability, ALP activity and extracellular matrix mineralization （P〈0.05）, while 18raM Mg2＋ group showed the opposite effect （P〈0.05）. The afore- mentioned beneficial effects afforded by 10 mM Mg2＋ were abolished by blocking the PI3K/Akt signaling pathway with addition ofwort- mannin. Conclusions： The viability and differentiation of osteoblasts were promoted by 6 and 10 mM Mg2＋, while inhibited by the 18 mM Mg2＋ The promotive effect of 10 mM Mg2＋ on viability and differentiation of osteoblasts attributed to the activation of the PI3K/Akt signaling pathway. This study could promisingly promote research and development of medical magnesium-based biomaterials.