Angiopoietins: multifaceted mediators in the pathogenesis of joint-related disorders.

Joint-related diseases often involve multiple aspects of angiogenesis, alterations in the extracellular matrix (ECM), and inflammatory responses, causing pain and mobility problems for patients. Angiopoietins (Angs) are a protein family of secreted growth factors that have a variety of functions, including regulating angiogenesis, stabilizing blood vessels, and mediating changes in the ECM. The first Ang was discovered by Davis in COS cells, and since then, three more members of this protein family have been discovered.