title: Combined effect of TNF-α and cyclic stretching on gene and protein expression associated with mineral metabolism in cementoblasts.
abstract: OBJECTIVE
  This work aims to investigate how the combination of TNF-α and cyclic stretching affects the expression of gene and protein associated with mineral metabolism in cementoblasts in vitro.
  
  
  METHODS
  Cementoblasts were cyclically stretched using the Flexcell tension system 4000 in the presence of 10 ng/ml TNF-α. Subsequently, the gene and protein expression CAP, Col I, BSP, OPG, RANKL and RUNX2 were detected using RT- PCR and ELISA/Western immunoblotting methods, respectively.
  
  
  RESULTS
  Cyclic stretching alone enhanced CAP, Col I, OPG, RANKL and RUNX2 expression in an amplitude manner, while decreased BSP expression. Expression of all these proteins was attenuated in the presence of TNF-α whether the cells were exposed to cyclic stretching or not. The ratio of RANKL/OPG was increased at any stimulation.
  
  
  CONCLUSIONS
  This results suggest that TNF-α affected the regulation of gene and protein expression induced by mechanical stimulation in cementoblasts. This may suppress anabolism and promote catabolism of cementum. It suggests that inflammatory cytokine may impair the cementum remodeling under mechanical stimulation.
authors.affiliation: College of Mechanics, Shanxi Key Laboratory of Material Strength & Structural Impact, Institute of Applied Mechanics and Biomedical Engineering, Taiyuan University of Technology, Taiyuan, Shanxi 030024, China; College and Hospital of Stomatology, Shanxi Medical University, Taiyuan, Shanxi 030012, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Yao
authors.affiliation: College of Mechanics, Shanxi Key Laboratory of Material Strength & Structural Impact, Institute of Applied Mechanics and Biomedical Engineering, Taiyuan University of Technology, Taiyuan, Shanxi 030024, China.
authors.forename: Xiaona
authors.initials: X
authors.lastname: Li
authors.affiliation: College and Hospital of Stomatology, Shanxi Medical University, Taiyuan, Shanxi 030012, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhao
authors.affiliation: College of Mechanics, Shanxi Key Laboratory of Material Strength & Structural Impact, Institute of Applied Mechanics and Biomedical Engineering, Taiyuan University of Technology, Taiyuan, Shanxi 030024, China.
authors.forename: Genlai
authors.initials: G
authors.lastname: Du
authors.affiliation: College of Mechanics, Shanxi Key Laboratory of Material Strength & Structural Impact, Institute of Applied Mechanics and Biomedical Engineering, Taiyuan University of Technology, Taiyuan, Shanxi 030024, China.
authors.forename: Pengfei
authors.initials: P
authors.lastname: Feng
authors.affiliation: College of Mechanics, Shanxi Key Laboratory of Material Strength & Structural Impact, Institute of Applied Mechanics and Biomedical Engineering, Taiyuan University of Technology, Taiyuan, Shanxi 030024, China. Electronic address: chenweiyi211@163.com.
authors.forename: Weiyi
authors.initials: W
authors.lastname: Chen
mesh_terms: D000818:Animals; D015153:Blotting, Western; D002460:Cell Line; D003739:Dental Cementum / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D015870:Gene Expression; D051379:Mice; D008903:Minerals / Q000378:metabolism*; D053244:Osteoprotegerin / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D053245:RANK Ligand / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D013314:Stress, Mechanical; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
chemical_list: D008903:Minerals; D053244:Osteoprotegerin; D011506:Proteins; D053245:RANK Ligand; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha
keywords: Cementoblasts; Cyclic stretching; Homeostasis; Mineral metabolism; Periodontitis; TNF-α