摘要
目的观察不同强度的周期性机械牵张应力对骨髓基质干细胞(BMSCs)氧自由基系统的影响。方法建立体外细胞周期性机械牵张应力加载装置,取材原代培养BMSCs,并进行细胞多向分化潜能检测,取3-5代细胞加载不同强度的应力(正弦波形,1Hz),干预后用二氯荧光素双醋酸盐免疫发光标志法上流式细胞仪检测活性氧(ROS)活性,取细胞悬液超声裂解后分别用黄嘌呤氧化酶法和硫代巴比妥酸法检测超氧化物歧化酶(SOD)、丙二醛(MDA)含量。结果高强度的机械应力(〉12%)可导致BMSCs的ROS活性增强、SOD表达下降、MDA含量增高,并且与作用时间呈依赖关系,其中实验组24%的高强度应力干预BMSCs 48h后,ROS的标志荧光强度(55.82±2.82)为对照组(4.51±1.64)的12.4倍,SOD活性[(5.77±0.68)μ/mL]较对照组[(27.00±1.65)μ/mL]降低约4/5,MDA含量[(4.47±0.18)μmol/mL]较对照组[(1.39±0.15)μmol/mL]增加3倍多。结论高强度(〉12%)的机械应力可导致BMSCs氧自由基系统平衡失调,对细胞有较大的毒性作用,过大的强度应力不利于骨骼生长,对于机械应力的临床应用有指导意义。
Objective To study effects of cyclical mechanical strains of different magnitudes on oxygen free radical system (ROS, SOD and MDA) in bone marrow stromal cells (BMSCs). Methods A mechanical stretching loading device was set up for cultured BMSCs. After BMSCs were stimulated by cyclical mechanical strains of different magnitudes, ROS labeled with (dichlorofluorescein, DCFH) fluorescent probe in BMSCs was detected by flow cytometry (FCM), while SOD and MDA were detected by xanthinoxidase method and thio-barbituric acid method. Results Mechanical strain of extreme magnitude (〉 12%) applied to BMSCs enhanced ROS synthesis, decreased the level of SOD and increased the level of MDA, in a time-and magnitude-dependent fashion. Condusions Since mechanical strain of extreme magnitude can induce disequilibrium of the oxygen free radical system, leading to cytotoxicity, it is harmful to the growth of bone. This finding may provide guidance for clinical application of mechanical strains.
出处
《中华创伤骨科杂志》
CAS
CSCD
2008年第1期59-63,共5页
Chinese Journal of Orthopaedic Trauma
基金
教育部回国人员启动基金项目(013456)
关键词
干细胞
骨髓
活性氧
超氧化物歧化酶
丙二醛
Myeloid progenitor cells
Reactive oxygen species
Superoxide dismutase
Malondialdehyde