流体剪切应力对模拟微重力下MG-63细胞骨架系统的影响  

Effect of Flow Shear Stress On Cytoskeleton in MG-63 Cells Cultured under Modeled Microgravity with Clinostat

作　　者：杜挺媛[1] 张舒[1] 曹新生[1] 王冰[1] 

机构地区：[1]第四军医大学航空航天医学国家教育部重点实验室,陕西西安710032

出　　处：《航天医学与医学工程》2012年第4期235-238,共4页Space Medicine & Medical Engineering

基　　金：国家自然科学基金项目(30600132;30700141;30870595;31170889)

摘　　要：目的观察水平回转模拟微重力(modeled microgravity,MMG)后人骨肉瘤MG-63细胞受流体剪切应力(flow shear stress,FSS)作用后细胞骨架的改变,探讨模拟微重力情况下骨质丢失的细胞学机制。方法 MG-63成骨细胞采用回转器水平回转培养48 h模拟微重力效应,同时设静止培养为对照组。之后,细胞随机分为两组,一组利用流室系统实施FSS,FSS设为1.5 Pa,作用时间60 min,另一组无FSS作用。细胞经过免疫荧光染色后,激光共聚焦显微镜观察细胞骨架系统的变化。结果 FSS作用后,MG-63细胞微丝和微管的形态和分布均发生变化,微丝可见多束状排列,荧光强度增强,出现粗的应力纤维;微管可见其极性中心移向细胞质外缘,细胞外层荧光量加重,有少量束状结构出现。MMG后,MG-63细胞的细胞骨架发生解聚和重排,微丝向核周集聚;微管发生断裂,变短,弯曲等变化。MMG后,再给予FSS刺激,微丝未能形成应力纤维,仅见微丝、微管在应力方向有拉长。结论 1.5 Pa,60 min流体剪切应力未能在回转模拟微重力后成骨细胞内诱导形成应力纤维。Objective To observe the changes in the cytoskeleton of human osteosarcoma MG-63 cells under flow shear stress （FSS） in modeled microgravity environment and to investigate the mechanism of osteopenia induced by simulated mierogravity. Methods MG-63 cells were used as osteoblast model. Two-dimensional ro- tating wall vessel （2D-RWV） was used to simulate mierogravity for 48 h. The other groups were kept in 1G as the control. After 48 h, the cells were randomly divided into two groups, one group was treated with 1.5 Pa FSS in a flow chamber for 60 min, while the other group without FSS. The cytoskeleton alteration was evalua- ted with laser confocal fluorescence microscopy after immunofluorescence staining. Results After FSS treat- ment, changes of morphology and distribution of MG-63 mierofilament and mierotubule occurred. Multiple ar- rays of filamentous actin and enhanced fluorescent labeling were observed and thick stress fibers were formed along the FSS direction. In addition, polar center moved towards the outer edge of the cytoplasm in microtu- bules, fluorescent labeling of the cell outer layer was enhanced, and small amount of bunchy structures ap- peared. After MMG, the eytoskeleton of MG-63 cells became disorder and reorganized, filamentous actin ag- gregated towards the nuclei, the microtubules became short and wavy, and had some disruption. FSS after MMG did not induce the formation of stress fiber. Slight elongation of microfilament and microtubule along the stress direction was observed. Conclusion The FSS during MMG can not induce the forming of stress fibers in MG-63 cells.

关 键 词：模拟微重力 回转器 流体剪切应力 MG-63细胞 细胞骨架 

分 类 号：R854[医药卫生—航空、航天与航海医学]