Correlation of endothelin-1 mRNA expression and bone structure in advanced osteoarthritis

Abstract Recent understandings of the vascular contribution of pathophysiology of osteoarthritis (OA) mount new evidence of cross-talking between subchondral bone tissue and articular cartilage that might have a decisive role in a pathophysiology of Osteoarthritis (OA). These understandings include blood flow (or interstitial fluid) impairment in subchondral bone. With regard to the mentioned role of the vasculature, the absence of custom nourishing to articular cartilage, and established, vasoconstrictive role of endothelin-1 (ET-1) it was reasonable to assume that ET-1 has an inconvertible role in pathophysiology of OA. Another moment in pathophysiology of OA is apoptosis of subchondral osteocytes, what induces osteoclastic resorption and at least temporarily reduces the bony support for the overlying cartilage. Since regional dependence of this protein’s expression was presumed, we suggest a regional division of subchondral bone by histomorphometrical analysis and quantification of identified protein by Real Time Polymerase Chain Reaction Analysis (RT-PCR). Obtained results should be compared to serum levels of soluble ET-1, what would enforce this methods validity. Herewith, a new screening marker of patients with osteoarthritis would be established. This would enable detection and follow-up of groups threatened by this, growing, cause of disability and decreased quality of life.