摘要
目的：探讨对体外培养成肌细胞施加不同牵张应力后细胞命运的改变,为临床合理施加矫形力提供理论依据。方法：利用Flexer cell细胞加力仪器与弹性加力板对体外培养C2C12成肌细胞施加不同频率、幅度的牵张应力,形变量代表应力幅度。通过MTT实验和PARP剪切实验测定在受到不同大小的牵张应力作用下（0%,5%,10%,15%,20%/10 cycles/min）的C2C12细胞的增殖和凋亡情况,通过检测细胞分化相关基因的表达改变,分析应力条件下细胞分化状态的改变。结果：5%的周期性应力可以促进细胞的增殖,同时抑制分化培养基诱导的细胞分化相关基因myogenin等的表达。当牵张应力大于10%后,可以观察到明显的DNA断裂。除此以外,我们还发现牵张应力大于10%后,细胞内开始出现大量的PARP剪切产物,随应力的增加而增多。当周期性牵张应力超过15%10cycles/min时,整体存活细胞数明显降低。结论：高强度牵拉介导的细胞凋亡,参与整体细胞数的减少,可能不利于组织的重塑和再生。
Objective To investigate the detailed effects of the cyclic stretches of a serial of magnitudes on cell growth,differentiation and apoptosis.C2C12 myoblasts were subjected to 0%,5%,10%,15%,20% /10 cycles / min cyclic stretch.Methods Flexercell stretch unit was applied in this study.We first evaluated cell viability upon serial cyclic stretches（0%,5%,10%,15%,20% /10 cycles / min）.MTT assay was applied to test cell viability and proliferation.Western blot of cleaved PARP was done to test the apoptosis.In addition,cell were induced in myogenic differentiation medium under serial cyclic stretches,differentiation gene marker myogenin was tested by RT-PCR.Results When the extension magnitude is about 5%,cell growth was facilitated.In contrast,myogenic medium induced cell differentiation under this condition was inhibited as seen by myogenin expression.With the extension magnitudes exceeding 15% 10cycles/min,cell viability decreased.Since both proliferation and cell death affected the MTT results,we then tested whether apoptosis was involved in the process.Abundant PARP cleavage was observed when the cyclic stretches were over 15%.Conclusions Low magnitude of stretch inhibited proliferation and promoted proliferation while excessive stretch induced apopsis.
出处
《中国美容医学》
CAS
2011年第7期1087-1089,共3页
Chinese Journal of Aesthetic Medicine
基金
国家自然科学基金资助（NSFC30900860）
关键词
周期性牵张应力
凋亡
增殖
分化
cyclic stretch
apoptosis
proliferation
differentiation
