title: Association between radiographic hand osteoarthritis and RANKL, OPG and inflammatory markers.
abstract: OBJECTIVE
  The aim of the study was to evaluate the association between prevalence and severity of radiographic hand osteoarthritis (OA) and serum levels of systemic inflammatory markers in a community-based population sample.
  
  
  METHODS
  A cross-sectional observational study was conducted on a population comprised 1452 Chuvashians (763 males, aged 49.23 ± 17.43; and 689 females, aged 50.37 ± 17.47 years). OA was evaluated in 14 joints of each hand using Kellgren and Lawrence (K-L), joint space narrowing (JSN) and osteophyte (OS) scores. Serum levels of systemic inflammatory and osteoclastogenic cytokines were measured by an enzyme-linked immunosorbent assay (ELISA). Statistical analyses included descriptive statistics, correlation analysis and multiple linear regressions.
  
  
  RESULTS
  Monocyte chemotactic protein-1 (MCP-1) and osteoprotegerin (OPG) levels were associated with OA traits, but the statistically significant correlations were weak and/or moderate. In particular, the MCP-1 inflammation marker showed a statistically significant association with JSN (β=0.077, P=0.022) and OS (β=0.067, P=0.024) scores, but not with the number of affected joints (K-L ≥ 2). OPG was significantly correlated with the scores as to the number of affected joints (β=0.063, P=0.035) and OS (β=0.077, P=0.028). No significant associations were found between levels of other inflammatory [interleukin (IL)-6, tumor necrosis factor (TNF)-α, IL-17] and osteoclastogenic [receptor activator for nuclear factor κ B ligand (RANKL), macrophage colony-stimulating factor (M-CSF)] cytokines and OA characteristics.
  
  
  CONCLUSIONS
  This study strengthens the premise that OPG might be a valid biomarker of hand OA. Confirmation of these results in larger cohorts of patients will reinforce our theory that the RANKL/OPG pathway is a suitable target for developing novel agents against OA.
authors.affiliation: Department of Biomedicine, Institute of Medical Biotechnology, Ministry of Education and Sciences, Tbilisi, Georgia.
authors.forename: I
authors.initials: I
authors.lastname: Pantsulaia
authors.forename: L
authors.initials: L
authors.lastname: Kalichman
authors.forename: E
authors.initials: E
authors.lastname: Kobyliansky
mesh_terms: D015415:Biomarkers / Q000097:blood; D018932:Chemokine CCL2 / Q000097:blood; D003430:Cross-Sectional Studies; D016207:Cytokines / Q000097:blood*; D005260:Female; D050823:Hand Joints / Q000000981:diagnostic imaging / Q000473:pathology*; D006801:Humans; D007249:Inflammation / Q000097:blood; D015850:Interleukin-6 / Q000097:blood; D016014:Linear Models; D016173:Macrophage Colony-Stimulating Factor / Q000097:blood; D008297:Male; D008875:Middle Aged; D010003:Osteoarthritis / Q000097:blood* / Q000000981:diagnostic imaging / Q000473:pathology*; D053244:Osteoprotegerin / Q000097:blood; D011859:Radiography; D053246:Receptor Activator of Nuclear Factor-kappa B / Q000097:blood; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
chemical_list: D015415:Biomarkers; D018932:Chemokine CCL2; D016207:Cytokines; D015850:Interleukin-6; D053244:Osteoprotegerin; D053246:Receptor Activator of Nuclear Factor-kappa B; D014409:Tumor Necrosis Factor-alpha; D016173:Macrophage Colony-Stimulating Factor