Analysis of Gene Expression Profile of Periodontal Ligament Cells Subjected to Cyclic Compressive Force

Abstract

Cyclic compressive force is an important mechanical stimulus on periodontal ligament (PDL). The differential expression of genes in PDL cells is thought to be involved in the remodeling of periodontal tissues subjected to mechanical stress. However, little is known about differentially expressed genes in PDL cells under cyclic compressive force. In our study, human PDL cells were subjected to 4000 μ strain compressive stress loading at 0.5 Hz for 2 h. The effect of mechanical stress on PDL cells proliferation was observed by flow cytometry. Microarray analysis was used to investigate the mechano-induced differential gene profile in PDL cells. Differential expression was confirmed by quantitative real-time polymerase chain reaction (RT-PCR) analysis on genes of interest and explored at two more force loading times (6 h, 12 h). After mechanical loading, cell proliferation was repressed. The microarray data showed that 217 out of 35,000 genes were differentially expressed; among the 217 genes, 207 were up-regulated whereas 10 were down-regulated (p < 0.05). Gene ontology analysis suggested that majority of differentially expressed genes were located in the nucleus and functioned as transcription factors involved in a variety of biological processes. Five genes of interest (IL6, IL8, ETS1, KLF10, and DLC1) were found to be closely related to negative regulation of cell proliferation. The PCR results showed increased expression after 2 h loading, then a decline with extended loading time. The signaling pathways involved were also identified. These findings expand understanding of molecular regulation in the mechano-response of PDL cells.

Intermittent compressive force promotes osteogenic differentiation in human periodontal ligament cells by regulating the transforming growth factor-β pathway

“…Although several studies investigated mRNA profiles, the comparison of gene expression in hPDLs subjected to different force types is lacking 10,38,39 . Uniaxial cyclic strain application induced genes related to cell cycle, apoptosis, and proliferation in hPDLs 40 . In contrast, static compressive force regulated genes related to the ECM, inflammatory cytokines, and cell growth 10 .…”

Role of DLC1 tumor suppressor gene and MYC oncogene in pathogenesis of human hepatocellular carcinoma: Potential prospects for combined targeted therapeutics

“…DLC1 is vital for normal development because null mutations in the gene result in embryonic lethality in mice and flies. It is also involved in insulin signaling and the pathogenesis of coronary spastic angina and is among four genes that negatively regulate periodontal ligament cell proliferation (56–59). …”

Cementogenesis is inhibited under a mechanical static compressive force via Piezo1

“…8 In the PDLCs, however, mechanical stimuli promote cell proliferation by influencing the duration of the S phase and mitotic activity. 25 Moreover, previous studies have shown that the osteoblastic marker expression increases in PDLCs under pressure, 26,27 while in the current study, these markers were reduced in cementoblast cells. The different characterization of these two cells may result in their different responses to compressive force.…”