模拟微重力对巨核细胞增殖和分化的影响

Effect of simulated microgravity on proliferation and differentiation of the human megakaryocyte cell

目的:探讨模拟微重力对巨核细胞增殖和分化的影响及机制。方法:利用RCCS-4模拟微重力,采用台盼蓝染色判断细胞活力,细胞计数及CCK8法评估细胞增殖情况,采用流式细胞术检测CD41+/CD61+细胞比例和细胞周期。RT-PCR法检测血小板生成素受体(c-mpl)和相关转录因子mRNA表达水平。结果:培养24、48、72 h后,SMG组细胞计数、CCK8法细胞增殖活性、G2/M期细胞比例、c-mpl mRNA表达水平均显著低于NG组(P<0.05);培养48、72 h后SMG组CD41+/CD61+细胞比例、Rant相关转录因子1(RUNX-1)mRNA表达水平显著低于NG组(P<0.05)。结论:模拟微重力抑制体外培养巨核细胞增殖和分化,转录受抑导致c-mpl表达下调进而c-mpl介导的下游通路受抑可能是相关机制。

Objective To investigate the effect of simulated microgravity on the proliferation and differentiation of the human megakaryocyte cells in vitro. Methods The fourth generation rotating cell culture system （RCCS-4） was used to generate the simulated microgravity environment. The cell viability was assessed by trypan blue staining method. The proliferation of cells was assessed by cell counting method and CCK8 method. The CD41^＋/CD61^＋ ceils rate and the cells cycle were detected by flow cytometry. The expression levels of thrombopoietin receptor （c-mpl） and transcription factors were detected with RT-PCR. Results After 24, 48, 72 h, culture under simulated microgravity resulted in a significant decrease in the cell number, proliferative activity, cells in the G2/M phase and levels of c-mpl mRNA expression in comparison with that under the normal gravity （P 〈 0.05）. After 48 h and 72 h culture, CD41^＋/CD61^＋ cells ratio decreased and RUNX-1 mRNA expression was down-regulated in cells of the group SMG compared with that of the group NG （P 〈 0.05）. Conclusion Microgravity can inhibit the proliferation and differentiation of human megakaryocyte cells in vitro. The mechanism may be that TPO/c-mpl pathway was inhibited by down regulating the expression of c-mpl which transcriptional inhibition lead to.