Response of human rheumatoid arthritis osteoblasts and osteoclasts to adiponectin.

Objectives: Adiponectin is an effector molecule in the pathophysiology of rheumatoid arthritis, e.g. by inducing cytokines and matrix degrading enzymes in synovial fibroblasts.

Expression of adipokines in osteoarthritis osteophytes and their effect on osteoblasts.

Objective: Osteophyte formation in osteoarthritis (OA) is mediated by increased osteoblast activity, which is -in turn- regulated by the Wnt signaling pathway. Obesity is regarded a risk factor in OA, yet little is known about the interaction between adipose tissue-derived factors, the adipokines, and bone formation, although adipokines are associated with the pathogenesis of OA. Therefore, the effect of adipokines on bone and cartilage forming cells and osteophyte development was analyzed.

Adipokines in bone disease.

Adipose tissue secretes highly bioactive factors, the adipokines. Systemic levels of adipokines are often altered in the presence of inflammation. In turn, adipokines affect different tissues and cells systemically as well as locally, contributing to immunomodulatory and bone remodelling mechanisms.

Differentiation of osteophyte types in osteoarthritis - proposal of a histological classification.

Objective: Osteoarthritis is not only characterized by cartilage degradation but also involves subchondral bone remodeling and osteophyte formation. Osteophytes are fibrocartilage-capped bony outgrowths originating from the periosteum. The pathophysiology of osteophyte formation is not completely understood.

Serum adipokine levels in patients with ankylosing spondylitis and their relationship to clinical parameters and radiographic spinal progression.

Objective: Adipokines have metabolic and inflammatory functions but can also affect bone metabolism. The purpose of this study was to determine the relationship between serum levels of adiponectin, resistin, and visfatin and markers of inflammation, disease activity, and radiographic spinal progression in patients with ankylosing spondylitis (AS).

Methods: Levels of adiponectin, resistin, and visfatin in the serum of 86 AS patients and 25 healthy controls were measured by enzyme-linked immunosorbent assay at baseline.