title: Role for interleukin-6 in structural joint damage and systemic bone loss in rheumatoid arthritis.
abstract: Interleukin-6 (IL-6) plays a key role in the local and systemic manifestations of rheumatoid arthritis (RA). IL-6 is not only a proinflammatory cytokine, but also interacts in complex ways with the cells involved in bone remodeling. In RA, IL-6 may indirectly promote osteoclastogenesis by increasing the release of RANK-L by osteoblasts and synovial cells. However, IL-6 inhibits osteoclastogenesis in vitro, via a direct mechanism. The effects of IL-6 on osteoblasts may vary with the cell differentiation stage: thus, IL-6 may promote the differentiation of pre-osteoblasts to mature osteoblasts while also diminishing the proliferation of osteoblasts at late differentiation stages. Thus, the effects of IL-6 on bone remodeling are complex and may occur in opposite directions depending on the model or experimental conditions. Nevertheless, results from studies in animal models and humans support a negative effect of IL-6 on bone. Thus, in patients with RA, blocking IL-6 may be effective both in diminishing the inflammatory manifestations and in preventing the bone complications of the disease.
authors.affiliation: Service de rhumatologie, Hôtel-Dieu, 1, place Alexis-Ricordeau, 44093 Nantes cedex 1, France. benlegoff@gmail.com
authors.forename: Benoit
authors.initials: B
authors.lastname: Le Goff
authors.forename: Frédéric
authors.initials: F
authors.lastname: Blanchard
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Berthelot
authors.forename: Dominique
authors.initials: D
authors.lastname: Heymann
authors.forename: Yves
authors.initials: Y
authors.lastname: Maugars
mesh_terms: D000818:Animals; D001172:Arthritis, Rheumatoid / Q000276:immunology* / Q000473:pathology*; D001862:Bone Resorption / Q000276:immunology* / Q000473:pathology*; D006801:Humans; D015850:Interleukin-6 / Q000276:immunology*; D007596:Joints / Q000276:immunology / Q000473:pathology; D019947:Receptors, Interleukin-6 / Q000276:immunology
chemical_list: D015850:Interleukin-6; D019947:Receptors, Interleukin-6