NAMPT (visfatin), a direct target of hypoxia-inducible factor-2α, is an essential catabolic regulator of osteoarthritis

Hypoxia-inducible factor 2α (HIF-2α), encoded by Epas1, causes osteoarthritic cartilage destruction by regulating the expression of matrix-degrading enzymes. We undertook this study to explore the role of nicotinamide phosphoribosyltransferase (NAMPT or visfatin) in HIF-2α-mediated osteoarthritic cartilage destruction.The expression of HIF-2α, NAMPT and matrix-degrading enzymes was determined at the mRNA and protein levels in human...