title: Age-related changes in expression of transforming growth factor-beta and receptors in cells of intervertebral discs.
abstract: OBJECTIVE
  The authors conducted a study to determine age-related changes in expression of transforming growth factor (TGF)-beta1, -beta2, -beta3, and Type I and Type II receptors in various cells in the nucleus pulposus and anulus fibrosus. Immunolocalization of TGFbetas and Type I and II receptors was examined during the aging process of cervical intervertebral discs in senescence-accelerated mice (SAM). The TGFbeta family has important roles for cellular function of various tissues. Its role in disc aging, however, is unknown. Detailed information on the temporal and spatial localization of TGFbetas and their receptors in discs is required before discussing introduction of them clinically into the intervertebral disc.
  
  
  METHODS
  Three groups of five SAM each were used. The groups of SAM were age 8, 24, and 50 weeks, respectively. Hematoxylin and eosin staining and immunohistochemical study involving specific antibodies for TGFbeta1, -beta2, -beta3, and Types I and II TGF receptors were performed. Intervertebral discs exhibited degenerative change with advancing age. The TGFbetas and their receptors were present in the fibrocartilaginous cells within the anulus fibrosus and notochord-like cells within the nucleus pulposus of young mice. Expression of TGFbetas and Type I and Type II receptors changed markedly in the cells within the anulus fibrosus during the aging process.
  
  
  CONCLUSIONS
  The TGFbetas and their receptors were present in cells within the nucleus pulposus and the anulus fibrosus of young mice, and their expression decreased with age.
authors.affiliation: Department of Orthopaedic Surgery, Faculty of Medicine, Kagoshima University, Kagoshima, Japan. shunji@m.kufm.kagoshima-u.ac.jp
authors.forename: Shunji
authors.initials: S
authors.lastname: Matsunaga
authors.forename: Satoshi
authors.initials: S
authors.lastname: Nagano
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Onishi
authors.forename: Norio
authors.initials: N
authors.lastname: Morimoto
authors.forename: Shusaku
authors.initials: S
authors.lastname: Suzuki
authors.forename: Setsuro
authors.initials: S
authors.lastname: Komiya
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D007150:Immunohistochemistry; D007403:Intervertebral Disc / Q000378:metabolism* / Q000473:pathology; D008297:Male; D051379:Mice; D008806:Mice, Inbred AKR; D008817:Mice, Mutant Strains; D018125:Receptors, Transforming Growth Factor beta / Q000378:metabolism*; D016212:Transforming Growth Factor beta / Q000378:metabolism*
chemical_list: D018125:Receptors, Transforming Growth Factor beta; D016212:Transforming Growth Factor beta