目的 探究紫草素对小鼠成骨前体细胞（MC3T3⁃E1 cells）增殖、成骨分化的影响及 OPG/ RANKL 信号轴在其中的作用。方法 MC3T3⁃E1 细胞体外培养，实验分为对照组和不同浓度（0.062 5、 0.125、0.25、0.5、1、2 μmol/L）紫草素实验组，给药 24、48、72 h 后 CCK⁃8 法检测细胞增殖抑制率；使用碱性 磷酸酶（ALP）活性试剂盒检测 MC3T3⁃E1 细胞 ALP 活性水平；运用 NBT/BCIP 试剂盒进行 ALP 染色鉴定； 采用实时荧光定量 PCR（RT⁃PCR）检测骨保护素（OPG）、核因子 κB 受体活化因子配体（RANKL）、Runt 相 关转录因子2（RUNX2）、Ⅰ型胶原（COL⁃I）基因表达水平；茜素红染色观察矿化结节的形成。结果 0.062 5、 0.125、0.25、0.5 μmol/L 的紫草素组较对照组显著促进 MC3T3⁃E1 细胞增殖（P < 0.05），高于 0.5 μmol/L 的紫 草素组显著抑制 MC3T3⁃E1 细胞生长（P < 0.05）；安全浓度下的紫草素组呈浓度依赖性促进成骨细胞增 殖、分化和矿化；RT⁃PCR 结果显示与对照组相比，安全浓度下的紫草素组显著促进 OPG、RUNX2、COL⁃I 表 达，抑制 RANKL 表达（P < 0.05）。结论 紫草素能促进 MC3T3⁃E1 细胞增殖、分化及矿化，可能是通过调 节OPG/RANKL 信号轴及成骨相关基因实现的。

Objective To investigate the effects of Shikonin on proliferation and osteogenic differentiation of mouse preosteoblast cells（MC3T3⁃E1 cells）and the role of OPG/ RANKL signaling axis. Methods MC3T3⁃E1 cells were cultured in vitro and divided into control group and different concentrations of shikonin group（0.0625， 0.125，0.25，0.5，1，2 μmol/L）. After 24，48，72 h of administration，Cell proliferation inhibition rate was detected by CCK⁃8 method；ALP activity of MC3T3⁃E1 cells was detected by alkaline phosphatase（ALP）activity kit. The NBT/BCIP kit was used to identify ALP staining. The expression levels of osteoprotegerin（OPG），nuclear factor κB receptor activating factor ligand（RANKL），Runt ⁃associated transcription factor 2（RUNX2）and type ⁃ I collagen （COL ⁃ I）genes were detected by Real ⁃time fluorescence quantitative PCR（RT ⁃PCR）；Alizarin red staining was used to observe the formation of mineralized nodules. Results Compared with the control group，0.0625，0.125， 0.25 and 0.5 μmol/L shikonin groups significantly promoted the proliferation of MC3T3⁃E1 cells（P < 0.05），while 0.5 μmol/L shikonin group significantly inhibited the growth of MC3T3⁃E1 cells（P < 0.05）. The safe concentration of shikonin group promoted the proliferation，differentiation and mineralization of osteoblasts in a concentration⁃ dependent manner. RT⁃PCR results showed that，when compared to the control group，the safe Shikonin concentra⁃ tion significantly increased the expression of OPG，RUNX2，and COL⁃I while inhibiting the expression of RANKL （P < 0.05）. Conclusions Shikonin can promote the proliferation，differentiation and mineralization of MC3T3⁃E1 cells，possibly by regulating the OPG/ RANKL signaling axis and osteogenic genes.