张、压应力刺激下人牙周膜成纤维细胞早期增殖活性和差异表达基因的变化

摘要

Objective The study was aimed to provide insights into cell proliferation ability alteration of human periodontal ligament fibroblasts (HPDLF) under two different types of stimulation, cyclic tensile and compressive stress, and screen the differentially expressed genes to have a comprehensive understanding of the molecular mechanism of changes in proliferation. Methods Primary HPDLF were subjected to cyclic tensile and compressive stress (0.5 Hz, 4 000 μ-strain) for 2 h through a four-point bending strain system. After that, cell proliferation ability was examined by flow cytometry. Then the gene expression profile was investigated by microarray analysis. Results Mechanical stress slowed a down proliferation of cells. S phase cells and proliferation index (PD decreased. Differentially expressed genes were mainly located at nucleus and focus in transcription factor activity related genes, and most of them were involved in the regulation of transcription factors. Among them, more were in group of compressive stress. Conclusion 1) Under mechanical loading, HPDLF proliferation were slowed and cell cycles were arrested. 2) Cell cycle arrest and the slow-down proliferation, which can be viewed as an adaptation and protection mechanism of cells to have more time to decide how to respond to mechanical stimuli, and the differential gene expression reflect the behavior of cells. The re-rnsult of the response is gene transcription changes at first, and the most important biological response is the nu-clear transcription. 3) HPDLF are more sensitive to cyc-lic compressive stress.%目的 对比在张应力和压应力两种不同性质力的刺激下人牙周膜成纤维细胞(HPDLF)增殖活性的变化,并对差异表达基因进行筛选,探讨不同应力作用后HPDLF增殖变化的分子机理.方法 使用四点弯曲加力装置对细胞进行0.5 Hz、4000 μstrain的应力加载,加载时间2h,采用流式细胞术测定张、压应力刺激对HPDLF增殖活性的影响,应用基因芯片技术检测两种应力刺激下细胞的差异表达基因.结果 在两种应力刺激作用下,S期细胞百分比和细胞增殖指数均降低；差异表达的基因最主要位于细胞核,集中在转录因子活性相关基因群,参与最多的生物过程为转录因子调控,其中压应力引起的差异表达基因和生物过程的数量较张应力更多.结论 1)周期性张、压应力作用下,HPDLF增殖变缓、细胞周期阻滞.2)细胞增殖变缓和细胞周期阻滞可看成是细胞对外界刺激的适应和自我保护,有利于HPDLF有更多的时间决定如何应答外界应力刺激,其应答的结果首先是转录水平上基因表达的改变,最主要的生物学反应是核转录调控.3)HPDLF对周期性压应力更敏感.