title: Age-related changes in the expression of gelatinase and tissue inhibitor of metalloproteinase genes in mandibular condylar, growth plate, and articular cartilage in rats.
abstract: Mandibular condylar cartilage acts as both articular and growth plate cartilage during growth, and then becomes articular cartilage after growth is complete. Cartilaginous extracellular matrix is remodeled continuously via a combination of production, degradation by matrix metalloproteinases (MMPs), and inhibition of MMP activity by tissue inhibitors of metalloproteinases (TIMPs). This study attempted to clarify the age-related changes in the mRNA expression patterns of MMP-2, MMP-9, TIMP-1, TIMP-2, and TIMP-3 in mandibular condylar cartilage in comparison to tibial growth plate and articular cartilage using an in situ hybridization method in growing and adult rats. MMP-2 and MMP-9 were expressed in a wide range of condylar cartilage cells during growth, and their expression domains became limited to mature chondrocytes in adults. The patterns of TIMP-1 and TIMP-2 expression were similar to those of MMP-2 and MMP-9 during growth, and were maintained until adulthood. TIMP-3 was localized to hypertrophic chondrocytes throughout the growth stage. Therefore, we concluded that TIMP-1 and TIMP-2 were general inhibitors of MMP-2 and MMP-9 in condylar cartilage, while TIMP-3 regulates the collagenolytic degradation of the hypertrophic cartilage matrix.
authors.affiliation: Division of Orthodontics and Dentofacial Orthopedics, Tohoku University Graduate School of Dentistry, Aoba-ku, Sendai, 980-8575, Japan, takahasi@mail.tains.tohoku.ac.jp
authors.forename: Ichiro
authors.initials: I
authors.lastname: Takahashi
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Onodera
authors.forename: Jin-Wan
authors.initials: JW
authors.lastname: Bae
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Mitani
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Sasano
authors.forename: Hideo
authors.initials: H
authors.lastname: Mitani
mesh_terms: D000375:Aging / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D002358:Cartilage, Articular / Q000201:enzymology / Q000378:metabolism*; D018093:Gelatinases / Q000235:genetics / Q000378:metabolism*; D006132:Growth Plate / Q000201:enzymology / Q000378:metabolism*; D006801:Humans; D008297:Male; D008335:Mandibular Condyle / Q000201:enzymology / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D019714:Tissue Inhibitor of Metalloproteinases / Q000235:genetics / Q000378:metabolism*
chemical_list: D012333:RNA, Messenger; D019714:Tissue Inhibitor of Metalloproteinases; D018093:Gelatinases