Role of Secreted Frizzled-Related Protein 1 and Tumor Necrosis Factor-α (TNF-α) in Bone Loss of Patients with Rheumatoid Arthritis

Bone loss is one of the emerging extra-articular manifestations of rheumatoid arthritis. TNF-α is the main inflammatory cytokine that can directly increase bone resorption. However, its role in bone formation is still unknown, especially related to secreted frizzled-related protein 1 (SFRP-1), an osteoblast inhibitor. This study examines the correlation between TNF-α and SFRP-1, with a bone turn over marker (CTX and P1NP). This is a...