Drs. Appel, Sieper, and Schett belong to the Spondyloarthritis Immunology Research Alliance (SpIRAL).
Altered skeletal expression of sclerostin and its link to radiographic progression in ankylosing spondylitis
Article first published online: 29 OCT 2009
Copyright © 2009 by the American College of Rheumatology
Arthritis & Rheumatism
Volume 60, Issue 11, pages 3257–3262, November 2009
How to Cite
Appel, H., Ruiz-Heiland, G., Listing, J., Zwerina, J., Herrmann, M., Mueller, R., Haibel, H., Baraliakos, X., Hempfing, A., Rudwaleit, M., Sieper, J. and Schett, G. (2009), Altered skeletal expression of sclerostin and its link to radiographic progression in ankylosing spondylitis. Arthritis & Rheumatism, 60: 3257–3262. doi: 10.1002/art.24888
- Issue published online: 29 OCT 2009
- Article first published online: 29 OCT 2009
- Manuscript Accepted: 11 JUL 2009
- Manuscript Received: 10 FEB 2009
- Deutsche Forschungsgemeinschaft. Grant Number: DFG; Ap 82/3-1
- START Prize from the Austrian Ministry of Sciences
- European Union projects Masterswitch, Kinacept, and Adipoa, Sonderforschungsbereich (SBF) 643, the Forschergruppe 661 of the DFG, and the Interdisciplinary Centre for Clinical Research Erlangen of the DFG
- German Ministry for Education and Research (BMBF)
Osteocytes are considered to be sensors of bone damage and regulators of bone mass by specifically expressing sclerostin, an inhibitor of bone formation. The contribution of osteocytes in regulating local bone remodeling in arthritis is unknown. The aim of this study was to investigate the role of osteocytes as contributors to bone remodeling in ankylosing spondylitis (AS).
Sclerostin expression and osteocyte death were assessed by immunohistochemistry in joints derived from patients with AS, patients with rheumatoid arthritis (RA), and patients with osteoarthritis (OA), as well as from control subjects. In addition, the serum level of sclerostin was assessed by enzyme-linked immunosorbent assay in healthy subjects and patients with AS; this assessment included the longitudinal correlation of sclerostin serum levels and radiographic progression in the spine of patients with AS.
Sclerostin expression was confined exclusively to osteocytes. Whereas the majority of osteocytes in healthy individuals and patients with RA were sclerostin positive, expression was significantly reduced in patients with OA and was virtually absent in patients with AS. Moreover, serum levels of sclerostin were significantly lower in patients with AS than in healthy individuals. Importantly, low serum sclerostin levels in patients with AS were significantly associated with the formation of new syndesmophytes (P = 0.007).
Sclerostin expression is impaired in patients with AS, suggesting a specific alteration of osteocyte function in this disease. A low serum level of sclerostin in the setting of AS is linked to increased structural damage, emphasizing the role of sclerostin in the suppression of bone formation.