血清对周期性张应变作用下成骨细胞凋亡的作用及机制研究  

Effect of serum on cyclic tensile stress manipulated osteoblast apoptosis

作　　者：李晅 王冬梅[2] 沈刚[3,4] 唐国华[3,4] 

机构地区：[1]上海市口腔病防治院口腔正畸科,上海200001 [2]上海交通大学机械与动力工程学院 [3]上海交通大学医学院附属第九人民医院口腔正畸科 [4]上海市口腔医学重点实验室

出　　处：《山西医科大学学报》2014年第8期699-703,共5页Journal of Shanxi Medical University

基　　金：国家自然科学基金资助项目(30500572)

摘　　要：目的研究血清对周期性张应变作用下体外培养的成骨细胞凋亡的影响。方法酶消化法分离培养新生SD大鼠颅顶骨成骨细胞,P2-P4代成骨细胞培养4 d后,使用Flexcell 4000TM细胞应变加载系统分别对细胞施加72 h变形率为6%和12%的等轴周期性张应变,总培养时间为7 d。根据应变加载时培养液中血清加载情况分为血清组和无血清组。运用流式细胞技术对成骨细胞凋亡水平进行检测,运用ELISA技术检测caspase-3表达,运用real time RT-PCR技术检测caspase-8和caspase-9的表达。结果不加力时,血清组成骨细胞凋亡率、caspase-3活性及caspase-9的表达显著低于无血清组,caspase-8表达无显著差异。6%的周期性张应变作用下,无血清组成骨细胞凋亡水平、caspase-3活性和caspase-8表达降低,caspase-9表达无明显改变,而血清组成骨细胞凋亡水平、caspase-3活性及caspase-9表达明显低于无血清组相应细胞的各项指标。12%的周期性张应变作用下,无血清组成骨细胞凋亡水平、caspase-3活性和caspase-8表达增高,caspase-9表达无明显改变,而血清组成骨细胞凋亡水平、caspase-3活性及caspase-9表达明显低于无血清组。周期性张应变作用下,血清组和无血清组caspase-8的表达无显著差异。结论无血清状态下周期性张应变对成骨细胞的凋亡有影响。血清通过caspase-9/caspase-3途径减弱周期性张应变对成骨细胞凋亡的影响。Objective To investigate the effect of serum on cyclic tensile stress manipulated osteoblast apoptosis in vitro.Methods Primary osteoblasts were harvested from neonatal rat calvaria by sequential enzyme digestion.Osteoblasts of passages 2 to 4 were used.After 4 d of static culture,the osteoblasts were subjected to cyclic equibiaxial cyclic tensile stress for 72 h using Flexcell 4000TM strain unit.Total culture time was 7 d.Cells were divided into serum group and serum starvation group based on the serum status while stretching.Apoptotic levels of the osteoblasts were quantified by flowcytometer.The caspase-3 activity was detected by ELISA,and the mRNA expression of caspase-8 and caspase-9 was tested using real time RT-PCR.Results In non-stretched cultures,the apoptosis of osteoblasts,caspase-3 activity and caspase-9 expression were significantly lower in serum group than in serum starvation group,and there was no significant difference in caspase-8 expression.The 6％ elongation led to the decreased apoptosis rate,caspase-3 activity and caspase-8 expression of osteoblasts in serum starvation group,while caspase-9 expression was not affected significantly.While the apoptosis rate,caspase-3 activity and caspase-9 expression were significantly lower in serum group than those in serum starvation group.The 12％ elongation of stretch force elicited an increase of osteoblast apoptosis,caspase-3 activity and caspase-8 expression in serum starvation group,and did not affect caspase-9 expression.The apoptosis rate,caspase-3 activity and caspase-9 expression were also lower in serum group than in serum starvation group.However,the caspase-8 expression was not found significantly different between serum group and serum starvation group.Conclasion Stretching force can manipulate apoptosis of osteoblast under serum starvation.Serum can decrease the effect of stretching force on osteoblast apoptosis through caspase-9/caspase-3 pathway.

关 键 词：周期性张应变 成骨细胞 细胞凋亡 CASPASE 

分 类 号：R329.2[医药卫生—人体解剖和组织胚胎学]