牵张应变诱导人牙周膜细胞凋亡信号通路初探

Study on stretching force-induced apoptosis mechanism of human periodontal ligament cells

目的通过研究Caspase酶在牵张应变作用下的变化,来初步探讨其引起人牙周膜细胞(HPDLCs)凋亡的可能机制。方法体外培养HPDLCs,利用动态机械应变细胞加载装置对HPDLCs加载1%、10%和20%的动态牵张应变6、12、24、48 h,利用酶标仪检测Caspase-3活性以及添加Caspase-8和Caspase-9阻断剂后Caspase-3活性。结果 Caspase-3活性具有一定的时间和应变值依赖性,各应变组细胞的Caspase-3活性在加载24 h时达到峰值,Caspase-9阻断剂可以显著降低Caspase-3的活性,而Caspase-8却并没有明显作用同时发现。结论 Caspase-9激活Caspase-3介导的凋亡通路参与了牵张应变诱导HPDLCs的凋亡。

Objective To explore the apoptosis mechanism of human periodontal ligament cells （ HPDLCs） induced by Caspase un-der stretching force. Methods HPDLCs were cultured in vitro, and cells were stretched by dynamic mechanical strain 1%, 10% and 20% for 6 h, 12 h, 24 h and 48 h. The Caspase？3 activity was measured after stretching in PDL cells that were treated with a specific inhibitor of either Caspase？8 or Caspase？9 prior to the application of stretching force. Results The activity of Caspase？3 increased sub-stantially in a time and force dependent manner after the application of a cyclic stretching force. It reached a peak at 24 h. The Caspase？9 inhibitor abolished the stretching force-induced activation of Caspase？3, whereas the Caspase？8 inhibitor demonstrated no effect. Con-clusion Cyclic stretching force can induce apoptosis in HPDLCs through the activation of Caspase？3 via the Caspase？9 signaling cas-cade.