title: Sclerostin and Dkk-1 in patients with ankylosing spondylitis.
abstract: OBJECTIVE
  To determine the serum Dickkopf-related protein 1 (Dkk-1) and sclerostin levels, and their relationship to structural damage and disease activity in patients with ankylosing spondylitis (AS), as well as to compare the serum Dkk-1 and sclerostin levels in patients receiving and not receiving anti-TNF-a treatment. MATERIALS AND METHOds: This cross-sectional study included 44 AS patients and 41 healthy age- and gender- -matched controls. Demographic data, disease activity parameters, and Bath Ankylosing Spondylitis Radiologic Index (BASRI) scores were recorded. Serum Dkk-1 and sclerostin levels were measured using commercially available ELISA.
  
  
  RESULTS
  Serum Dkk-1 levels were lower (P > 0.05) and sclerostin levels were significantly lower (P < 0.05) in the AS patients than in the controls. Dkk-1 and sclerostin levels were similar in the patients that did and didn't receive anti-TNF-a treatment, and in the patients with active and inactive disease (P > 0.05). There wasn’t a correlation between serum Dkk-1 or sclerostin levels, and disease activity indices (P > 0.05). BASRI scores did not correlate with serum Dkk-1 or sclerostin levels (P > 0.05). DISCUSSIOn: Sclerostin expression is impaired in AS, but this is not the case for Dkk-1. The lack of an association between Dkk-1 or sclerostin levels, and anti-TNF-a treatment, disease activity indices, and radiological damage might indicate that neither the Dkk-1 nor sclerostin level induce inflammation and radiological damage in AS patients. Pathologic bone formation in AS might be due to molecular dysfunction of sclerostin and Dkk-1 at the cellular level.
authors.forename: N
authors.initials: N
authors.lastname: Ustun
authors.forename: F
authors.initials: F
authors.lastname: Tok
authors.forename: U
authors.initials: U
authors.lastname: Kalyoncu
authors.forename: S
authors.initials: S
authors.lastname: Motor
authors.forename: R
authors.initials: R
authors.lastname: Yuksel
authors.forename: A E
authors.initials: AE
authors.lastname: Yagiz
authors.forename: H
authors.initials: H
authors.lastname: Guler
authors.forename: A D
authors.initials: AD
authors.lastname: Turhanoglu
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000328:Adult; D019485:Bone Morphogenetic Proteins / Q000097:blood*; D003430:Cross-Sectional Studies; D005260:Female; D005819:Genetic Markers; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000097:blood*; D008297:Male; D013167:Spondylitis, Ankylosing / Q000097:blood* / Q000188:drug therapy; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D019485:Bone Morphogenetic Proteins; C501126:DKK1 protein, human; D005819:Genetic Markers; D036341:Intercellular Signaling Peptides and Proteins; C422903:SOST protein, human; D014409:Tumor Necrosis Factor-alpha