Periarticular bone loss in antigen-induced arthritis.

• Objective: Bone loss in arthritis is a complex process including bone erosions, periarticular and generalized bone loss. The antigen-induced arthritis (AIA) model is mainly used to study synovitis and joint destruction, including bone erosions, while periarticular bone loss is less investigated. The main aim of this study was to characterize and establish AIA as a model for periarticular bone loss. We also determined the importance of NADPH oxidase 2 (NOX2) derived reactive oxygen species (ROS) for periarticular bone loss. Methods: AIA was induced in one knee by a local antigen injection and the other knee was used as non-arthritic control. At termination the knees were collected for histology. Periarticular bone mineral density (BMD) was investigated using peripheral Quantitative Computed Tomography (pQCT). Flow cytometry analyses were performed on synovial and bone marrow cells. Results: AIA resulted in decreased periarticular trabecular BMD and increased frequencies of preosteoclasts, neutrophils and monocytes in the arthritic synovial tissue. Arthritis resulted in an elevated capability to produce ROS. However, AIA induction in Ncf1(*/*) mice, lacking NOX2 derived ROS, and control mice resulted in similar reduction in periarticular trabecular BMD. Conclusions: AIA resulted in periarticular bone loss associated with local effects on inflammatory cells and osteoclasts. Furthermore, using this model, we conclude that NOX2 derived ROS production is not essential for inflammation-mediated periarticular bone loss. Thus, AIA can be used as a model to investigate the pathogenesis of local inflammation-mediated bone loss. © 2013 American College of Rheumatology.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Reumatologi och inflammation (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Rheumatology and Autoimmunity (hsv//eng)

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Endokrinologi och diabetes (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Endocrinology and Diabetes (hsv//eng)

Publication and Content Type

ref (subject category)

art (subject category)