title: Time course investigation of intervertebral disc degeneration in a rat-tail puncture model.
abstract: OBJECTIVE
  Intervertebral disc (IVD) degeneration was believed to contribute to lower back pain. The aim of the study was to investigate the pathogenesis and regulatory mechanism of puncture-induced IVD degeneration.
  
  
  METHODS
  We established a rat-tail puncture model using Kirschner wire and a homemade stopper. The progress of disc degeneration was evaluated by histological examination and the quantitative measurement of type I, type II collagen and other factors expression at 0.5, 1, 2, 6, and 12weeks after puncture and was compared with control rats of the same age.
  
  
  RESULTS
  Histological examination and Safranin-O staining revealed progressive degeneration of the punctured disc. Matrix metalloproteinase 13 (MMP13) was increased at 1week after puncture but did not change in the control group. The interleukin-1 beta (IL-1β) mRNA expression level was elevated at the acute stage after puncture compared with the control group. The hypoxia inducible factor 2 (HIF-2) increased expression in punctured groups. Additionally, compare to adjacent non-punctured segments, HIF-2α expression level transiently increased and then decreased in the nucleus pulposus immediately following puncture, and it then increased 12weeks after puncture.
  
  
  CONCLUSIONS
  The degenerative changes observed in this rat-tail puncture model are similar to human disc degeneration and that this model may be valuable for elucidating the molecular mechanisms and pathways underlying disc degeneration.
authors.affiliation: Institute of Traditional Medicine, National Yang Ming University, Taipei, Taiwan; Department of Orthopaedics, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan.
authors.forename: Chia-Hsian
authors.initials: CH
authors.lastname: Chen
authors.affiliation: Department of Orthopaedics, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan; Department of Orthopaedics, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
authors.forename: Chang-Jung
authors.initials: CJ
authors.lastname: Chiang
authors.affiliation: Department of Orthopaedics, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan.
authors.forename: Lien-Chen
authors.initials: LC
authors.lastname: Wu
authors.affiliation: Department of Orthopedic Surgery, Everan Hospital, Taichung, Taiwan.
authors.forename: Chih-Hong
authors.initials: CH
authors.lastname: Yang
authors.affiliation: Department of Orthopaedics, Taipei Medical University Hospital, Taipei Medical University, Taipei, Taiwan; Department of Orthopaedics, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
authors.forename: Yi-Jie
authors.initials: YJ
authors.lastname: Kuo
authors.affiliation: Department of Orthopaedics, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan; Department of Orthopaedics, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan. Electronic address: tsuangyh@gmail.com.
authors.forename: Yang-Hwei
authors.initials: YH
authors.lastname: Tsuang
authors.affiliation: Institute of Traditional Medicine, National Yang Ming University, Taipei, Taiwan; Department of Education and Research, Taipei City Hospital, Taipei, Taiwan. Electronic address: thtsai@ym.edu.tw.
authors.forename: Tung-Hu
authors.initials: TH
authors.lastname: Tsai
mesh_terms: D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000378:metabolism; D024042:Collagen Type I / Q000378:metabolism; D024043:Collagen Type II / Q000378:metabolism; D004195:Disease Models, Animal; D053583:Interleukin-1beta / Q000378:metabolism; D055959:Intervertebral Disc Degeneration / Q000378:metabolism / Q000473:pathology*; D008297:Male; D053509:Matrix Metalloproteinase 13 / Q000378:metabolism; D000070614:Nucleus Pulposus / Q000378:metabolism / Q000473:pathology; D011677:Punctures; D017207:Rats, Sprague-Dawley; D013623:Tail; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D015854:Up-Regulation; D000099162:Endothelial PAS Domain-Containing Protein 1
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D024042:Collagen Type I; D024043:Collagen Type II; D053583:Interleukin-1beta; D053509:Matrix Metalloproteinase 13; D014409:Tumor Necrosis Factor-alpha; D000099162:Endothelial PAS Domain-Containing Protein 1
keywords: HIF-2; Intervertebral disc degeneration; Nucleus pulposus; Rat-tail puncture model