镁合金对骨髓间充质干细胞增殖及成骨分化的影响研究

目的：探讨镁合金对人骨髓间充质干细胞（BMSCs）增殖及成骨分化的影响。方法抽取人骨BMSCs并予以鉴定；采用AZ31B镁合金浸提液培养人BMSCs 1、3、5、7 d，以普通培养基为对照组，CCK-8法检测细胞增殖活性；应用浸提液培养人BMSCs，诱导分化后检测成骨分化相关基因（COLⅠ、ALP、OPN）的表达。另设置调节pH值AZ31B组（pH-AZ31B组），以观察pH值变化对实验结果的影响。结果 BMSCs表达CD34（-）、CD45（-）、CD44（＋）、CD73（＋）、CD90（＋）、CD105（＋）。浸提液培养1、3、5、7 d，AZ31B组细胞相对增殖率低于对照组（P＜0.05），毒性评级为2级；对照组和pH-AZ31B组细胞活性较好，两组细胞相对增殖率比较，差异无统计学意义（P ＞0.05）。AZ31B组COLⅠ基因表达量与对照组比较，差异无统计学意义（P ＞0.05）；AZ31B组ALP基因表达量较低（P＜0.05），pH-AZ31B组与对照组无显著差异（P＞0.05）；AZ31B组OPN基因表达量在诱导分化后6 d、12 d显著高于对照组（P＜0.05），pH-AZ31B组与对照组无显著差异（P＞0.05）。结论镁合金对BMSCs增殖及成骨分化无不良影响，其影响可能与浸提液pH值的变化有关。

The influence of magnesium alloy on the cell proliferation and osteogenic differentiation of human bone marrow mesenchymal stem cells

Objective To investigate the influence of magnesium alloy on the cell proliferation and osteogenic differentiation of human bone marrow mesenchymal stem cells （BMSCs）. Methods BMSCs were extracted and identified, then cultured for 1, 3, 5, 7 d in magnesium alloy （AZ31B） leaching liquids, normal culture medium were used as control. Cell proliferation activity was detected by CCK-8 method; Human BMSCs were cultured in the extracts, followed by induction of differentiation, the expression of osteogenic differentiation-related gene （COLⅠ、ALP、OPN） were detected. pH-adjusted AZ31B group （pH-AZ31B） was added to observe the influence of pH value changes on the experimental results. Results BMSCs expressed CD34 （-）, CD45（-）, CD44 （＋）, CD73 （＋）, CD90 （＋）, CD105 （＋）. Cell relative growth rate in AZ31B group was lower than that of control group at 1, 3, 5, 7 d after the co-culture with alloy extracts （P 〈0.05）, toxicity in AZ31B group was rated as 2 grade; while cell activities were good in control group as well as in pH-AZ31B group （P 〉0.05）. No statistical difference was found between AZ31B group and control group in COLⅠ gene expression （P 〉0.05）; ALP expression in AZ31B group was relatively low compared with those in pH-AZ31B and control groups, and there was no statistical difference between pH-AZ31B group and control group （P 〉0.05）; OPN gene expression in AZ31B group was significantly higher than control group at 6 and 12 d after differentiation induction （P〈0.05）, but no statistical difference was found between control group and pH-ZA31B group （P 〉0.05）. Conclusion Magnesium alloy AZ31B do not have adverse effects on cell proliferation and osteogenic differentiation of BMSCs, the effects may be related to the changes of pH value in leaching liquids.