Expression analysis of a-smooth muscle actin and tenascin-C in the periodontal ligament under orthodontic loading or in vitro culture  

作　　者：Hui Xu Ding Bai L-Bruno Ruest Jian Q Feng Yong-Wen Guo Ye Tian Yan Jing Yao He Xiang-Long Han 

机构地区：[1]State Key Laboratory of Oral Diseases,Department of Orthodontics,West China Hospital of Stomatology,Sichuan University [2]Department of Biomedical Sciences,Baylor College of Dentistry,Texas A&M University

出　　处：《International Journal of Oral Science》2015年第4期232-241,共10页国际口腔科学杂志（英文版）

基　　金：funded by National Nature Science Foundation of China (Grant Nos 30970705, 11172190, 81371171, and 81371172)

摘　　要：α-smooth muscle actin （α-SMA） and tenascin-C are stress-induced phenotypic features of myofibroblasts. The expression levels of these two proteins closely correlate with the extracellular mechanical microenvironment. We investigated how the expression of α-SMA and tenascin-C was altered in the periodontal ligament （PDL） under orthodontic loading to indirectly reveal the intrinsic mechanical microenvironment in the PDL. In this study, we demonstrated the synergistic effects of transforming growth factor-β1 （TGF-β1） and mechanical tensile or compressive stress on myofibroblast differentiation from human periodontal ligament cells （hPDLCs）. The hPDLCs under higher tensile or compressive stress significantly increased their levels of α-SMA and tenascin-C compared with those under lower tensile or compressive stress. A similar trend was observed in the tension and compression areas of the PDL under continuous light or heavy orthodontic load in rats. During the time-course analysis of expression, we observed that an increase in α-SMA levels was matched by an increase in tenascin-C levels in the PDL under orthodontic load in vivo. The time-dependent variation of α-SMA and tenascin-C expression in the PDL may indicate the time-dependent variation of intrinsic stress under constant extrinsic loading.α-smooth muscle actin （α-SMA） and tenascin-C are stress-induced phenotypic features of myofibroblasts. The expression levels of these two proteins closely correlate with the extracellular mechanical microenvironment. We investigated how the expression of α-SMA and tenascin-C was altered in the periodontal ligament （PDL） under orthodontic loading to indirectly reveal the intrinsic mechanical microenvironment in the PDL. In this study, we demonstrated the synergistic effects of transforming growth factor-β1 （TGF-β1） and mechanical tensile or compressive stress on myofibroblast differentiation from human periodontal ligament cells （hPDLCs）. The hPDLCs under higher tensile or compressive stress significantly increased their levels of α-SMA and tenascin-C compared with those under lower tensile or compressive stress. A similar trend was observed in the tension and compression areas of the PDL under continuous light or heavy orthodontic load in rats. During the time-course analysis of expression, we observed that an increase in α-SMA levels was matched by an increase in tenascin-C levels in the PDL under orthodontic load in vivo. The time-dependent variation of α-SMA and tenascin-C expression in the PDL may indicate the time-dependent variation of intrinsic stress under constant extrinsic loading.

关 键 词：α-smooth muscle actin mechanical load MYOFIBROBLAST periodontal ligament TENASCIN-C transforming growthfactor-β1 

分 类 号：R783.5[医药卫生—口腔医学]