title: The relationship between ultra-short telomeres, aging of articular cartilage and the development of human hip osteoarthritis.
abstract: BACKGROUND
  Ultra-short telomeres caused by stress-induced telomere shortening are suggested to induce chondrocyte senescence in human osteoarthritic knees. Here we have further investigated the role of ultra-short telomeres in the development of osteoarthritis (OA) and in aging of articular cartilage in human hips.
  
  
  METHODS
  Cartilage was obtained from four different distances of the central weight-bearing area in human femoral heads (14 OA and 9 non-OA). Samples were split into three: one for quantification of ultra-short single telomeres by Universal STELA and mean telomere length measurement by Q-PCR; one for histological grading of OA, and one for immunohistochemical staining.
  
  
  RESULTS
  Load of ultra-short telomeres increased closer to the central weight-bearing area and correlated with cartilage degradation in both OA and non-OA samples. Mean telomere length decreased with decreasing distance to the central weight-bearing area, however, unexpectedly increased in the most central zone. This increase was associated with immunohistochemical findings of cells expressing markers characteristic of progenitor-like cells.
  
  
  CONCLUSIONS
  These findings suggest a role of short telomeres in the development of OA and in aging of articular cartilage. Furthermore, progenitor-like cells with long telomeres may be recruited to the most damaged areas of the cartilage.
authors.affiliation: Department of Clinical Genetics, Vejle/Lillebaelt Hospital, Kabbeltoft 25, 7100 Vejle, Denmark; Institute of Regional Health Research, University of Southern Denmark, J.B. Winsloews Vej 19,3., 5000 Odense C, Denmark; Danish Aging Research Center, University of Southern Denmark, J.B. Winsloews Vej 9B, 5000 Odense C, Denmark. Electronic address: maria.harbo@rsyd.dk.
authors.forename: M
authors.initials: M
authors.lastname: Harbo
authors.forename: J M
authors.initials: JM
authors.lastname: Delaisse
authors.forename: P
authors.initials: P
authors.lastname: Kjaersgaard-Andersen
authors.forename: F B
authors.initials: FB
authors.lastname: Soerensen
authors.forename: S
authors.initials: S
authors.lastname: Koelvraa
authors.forename: L
authors.initials: L
authors.lastname: Bendix
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D019644:Arthroplasty, Replacement, Hip; D002358:Cartilage, Articular / Q000473:pathology*; D016922:Cellular Senescence; D019902:Chondrocytes / Q000166:cytology / Q000378:metabolism; D005260:Female; D005270:Femur Head / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000235:genetics* / Q000473:pathology*; D016133:Polymerase Chain Reaction; D013234:Stem Cells / Q000166:cytology; D013314:Stress, Mechanical; D016615:Telomere / Q000648:ultrastructure*; D059506:Telomere Shortening
keywords: Aging; Chondrocytes; OA; Osteoarthritis; STELA; Telomere length; Ultra-short telomeres; osteoarthritis; single telomere length assay