Sudachitin, a Polymethoxyflavone Derived From Citrus Sudachi, Suppresses Lipopolysaccharide-Induced Inflammatory Bone Resorption Because of Inhibiting Osteoclast Formation in Mice

Inflammatory bone diseases are associated not only with production of inflammatory cytokines but also with local oxidative state. Sudachtin, a polymethoxyflavone derived from Citrus sudachi, possesses antioxidant properties and regulates various functions of mammalian cells.1 However, the mechanism for osteoclastogenesis and inflammatory bone destruction remains unknown. Extensive studies have indicated that the induction of osteoclast differentiation by RANKL requires the activation of NF-kB and MAPK signaling pathways, which leads to the expression of NFATc1, a critical transcription factor for osteoclast differentiation. NFATc1, in turn, induces osteoclast formation and bone-resorbing activity.