17β-雌二醇对大鼠骨髓基质干细胞成骨分化初期细胞骨架的影响

Effects of 17β-estradiol on the cytoskeleton of cultured bone mesenchymal stem cells in vitro

目的研究17β-雌二醇（17β-estriol，17β-E2）促进体外培养的大鼠骨髓幕质干细胞（bone mesenchymal stem cells，BMSCs）骨向分化过程中细胞骨架的变化。方法采用全骨髓培养法体外培养大鼠BMSCs，分为阴性对照组、阳性对照组（成骨细胞诱导液）和雌激素处理组（成骨细胞诱导液＋10^-6。mol／L。17β-E2），使用碱性磷酸酶（alkaline phosphatase，AI，P）试剂盒检测BMSCs的ALP活性，激光扫描共聚焦显微镜观察各组BMSCs成骨分化初期的细胞骨架。结果BMSCs细胞ALP活性随时间的增加而增强，雌激素处理组表达ALP活性明显高于阴性对照组和阳性对照组（P〈0．01）；细胞骨架荧光强度定量分析显示，雌激素处理组（26．56％±9．87％）较阳性对照组（18．31％±5．76％）和阴性对照组（8．12％土4．42％）明显增强（P〈0．05）。结论17β—E2可能通过早期调节细胞骨架微丝聚合改变细胞形态，从而促进骨髓基质干细胞向成骨分化。

Objective To explore the effects of 17β-estradiol （17β-E2） on cytoskeletalremodeling in osteogenic differentiation process of rat bone mesenchymal stem cells （BMSCs）. Methods Whole bone marrow culture method was used to amplify the BMSCs in vitro. The cultivated cells were randomly divided into negative control group, positive control group, and 17β-E2 group. The changes of alkaline phosphatase （ALP） activity were examined by ALP kit and the change of actin was observed by laser scanning con{ocal microscope. Results The ALP activity of BMSCs was increased with time. ALP activity in 17β-E2 group was significantly higher than that in two control groups. The quantitative analysis showed that cytoskeleton fluorescence intensity of BMSCs in 17β-E2 group （26.56 %± 9.87 % ） was apparently higher than that in positive control group （ 18.31%±5.76%） and in negative control group （8.12%±4.42%） （P〈0.05）. Conclusions 17β-estradiol increases the osteogenic differentiation capacity of BMSCs by enhancing cytoskeleton.