模拟失重对NIH3T3细胞纺锤体结构和细胞周期的影响

Effects of Simulated Weightlessness on Spindle Apparatus structure and Cell Cycle of NIH3T3 Fibroblasts

目的探讨模拟失重对成纤维细胞纺锤体结构和细胞周期的影响。方法采用双向多样本回转器(2D-RWVs)在30r/min转速下分别培养24、28和72h,模拟失重效应,以NIH3T3作为成纤维细胞模型,激光共聚焦显微镜研究细胞骨架系统的变化,并计算纺锤体结构异常比率。利用流式细胞仪检测细胞周期的变化。结果模拟失重对NIH3T3细胞微丝在3个时间点的影响不明显,微管系统在48h和72h产生解聚,纺锤体异常率在48h、72h均有显著性增高(P<0.01)。回转24、48和72h时S期细胞显著增加,而G2/M期细胞却明显减少。结论 NIH3T3细胞在模拟失重环境中造成微管系统损伤,处于分裂相的细胞纺锤体异常率显著增高,细胞周期阻滞在S期。

Objective To investigate the effect of simulated weightlessness on spindle apparatus and cell cycle of fibroblast cell line NIH3T3. Methods Two-dimensional rotating wall vessel （2D-RWV） was used to simulate weightlessness at 30 r/min for 24,48 and 72 h respectively. The cytoskeleton alteration was evaluated with laser confocal fluorescence microscopy, and the aberrant rate of spindle apparatus was calculated. The changes of cell cycle were examined with flow cytometry. Results No significant effect was observed on the microfilaments in NIH3T3 at three time-points. However, depolymerization of microtubules was found at 48 h and 72 h. Aberrant spindle rate of NIH3T3 at 48 h and 72 h were significantly higher （P0.01） than that of control group. Cell cycle distribution showed that there was a significant increase in S phase at 24 h, 48 h and 72 h, while the G2/M phase decreased significantly. Conclusion Simulated weightlessness effect leads to damage of microtubules in NIH3T3 cells and significant increase of mitotic spindle aberrant rate, which might result in S phase arrest of the NIH3T3 cells.