体外不同动态力学应变对人牙周膜成纤维细胞增殖和功能活性的影响

Effect of different dynamic mechanical strain on the proliferation and synthetic function of human periodontal ligament fibroblasts in vitro

目的探讨体外培养的人牙周膜成纤维细胞(HPDLF)在动态力学微应变范围内细胞增殖和功能活性的变化。方法采用四点弯曲细胞力学加载装置对体外培养的HPDLF进行加载,通过流式细胞术(FCM)分析细胞周期的改变和定量分析细胞总蛋白含量和碱性磷酸酶(ALP)活性,研究不同作用方式、大小和时间的动态力学应变对细胞增殖和功能活性的影响。结果加载装置所产生的动态力学微应变范围对HPDLF的G0/G1期、S期细胞百分比、增殖指数PI、总蛋白含量及ALP活性产生明显的影响(P<0.05),其中G0/G1期细胞百分比减少,S期细胞百分比、PI、总蛋白含量及ALP活性增高,且此影响均与应变的大小和作用时间密切相关;动态力学应变加载方式的不同对HPDLF的G0/G1期、S期、G2/M期细胞百分比、PI、总蛋白含量及ALP活性均有明显的影响(P<0.05),梯度加载组的促增殖和对总蛋白含量及ALP活性的上调作用均明显高于1000、4000μstrain两组。结论HPDLF细胞增殖和功能活性增加与动态力学应变的作用方式、应变大小、作用时间密切相关。

Objective To study the changes in the proliferation and synthetic function of human periodontal ligament fibroblasts（HPDLF） in response to dynamic mechanical strains of different modes,magnitudes and durations.Methods Using a 4-point bending system,the effect of dynamic mechanical strains of different modes,magnitudes and durations on the proliferation of HPDLF was investigated by analyzing the cell cycle changes with flow cytometry（FCM）,and the total protein level and the activity of alkaline phosphatase（ALP） in HPDLF were assayed by quantitative analysis.Results The percentage of G0/G1 cell decreased,S phase cells increased,and the proliferation index（PI）,total protein level and activity of ALP were augmented significantly in response to dynamic mechanical micro-strains.These changes showed close correlations to the magnitude and duration of the strain.The mode of strain caused significant changes in G0/G1,S,and G2/M phase cell percentages as well as the PI,total protein level and ALP activity of the cells.In the gradient strain group,the cell proliferation activity,total protein level and ALP activity were obviously higher than those in 1000 and 4000 μstrain groups.Conclusion The changes in the proliferation and synthetic function of HPDLF are closely correlated to the mode,magnitude and duration of the strains.