模拟失重骨细胞条件培养基对成骨细胞活性的影响

Effects of Conditioned Medium of Osteocytes Subjected to Simulated Weightlessness on Activity of Osteoblasts

目的探讨三维随机回转模拟失重培养后的骨细胞条件培养基(RCM)对成骨细胞活性的调节作用。方法采用三维随机回转模拟失重培养小鼠骨细胞系MLO-Y448h后,收集回转条件培养基(RCM)和未回转对照组的条件培养基(CCM),用四甲基偶氮唑盐比色(MTT)法、对硝基苯磷酸(pNPP)法和流式细胞术(FCM)检测RCM对小鼠成骨样细胞系MC3T3-E1增殖、周期及细胞分泌碱性磷酸酶(ALP)活性的影响。结果三维随机回转48h后的MLO-Y4RCM可促进MC3T3-E1增殖,用100%的MLO-Y4RCM和CCM培养MC3T3-E148h和72h后,RCM组比CCM组分别增加了1.21和1.27倍,差异性极显著(P<0.001);周期检测结果表明,RCM可以使MC3T3-E1越过周期阻滞点(S期);MC3T3-E1的ALP活性在RCM组和CCM组之间无差异。结论三维随机回转模拟失重培养骨细胞48h后的条件培养基促进了成骨细胞的增殖;并使成骨细胞的周期越过阻滞点,对成骨细胞的ALP活性无影响。

Objective To investigate the regulating effects of conditioned medium of rotation （RCM） of osteocytes subjected to simulated weightlessness on osteoblasts. Methods Conditioned medium of mouse osteocyte-like cell line MLO-Y4 was subjected to simulated weightlessness for 48 h with rondom positioning machine （RPM）.Its effects on proliferation,cell cycle and ALP activity of MC3T3-E1 were tested with MTT（methyl thiazolyl tetrazolium）,pNPP（p-Nitrophenyl Phosphate ） and flow cytometry respectively and compared with the effect of conditioned medium of control（CCM） which was not subjected to simulated weightlessness. Results After MC3T3-E1 were cultured for 48 h and 72 h,100% conditioned medium of rotation （RCM） of MLO-Y4 after simulated weightlessness for 48 h significantly stimulated proliferation of MC3T3-E1 cells as compared with conditioned medium of control （CCM）.The rate of proliferation in RCM was 1.21 and 1.27 fold as compared wtih CCM,respectively（P〈0.001）. In cell cycle assay RCM made MC3T3-E1 to overcome cell cycle arrest of S phase. There was no difference between RCM and CCM on ALP activity of MC3T3-E1 cells. Conclusion After 48 h simulated weightlessness,RCM of osteocytes promotes proliferation of osteoblasts and makes osteoblasts to overcome cell cycle arrest. There is no effects of RCM of osteocytes on ALP activity of osteoblasts.