8-Epixanthatin Suppresses RANKL-Induced Osteoclast Differentiation via Inhibition of NF-κB and MAPK Signaling.

Osteoclast hyperactivity represents a central mechanism in pathological bone destruction, underscoring the importance of discovering novel anti-resorptive compounds. In this study, we present early-stage evidence that 8-Epixanthatin can inhibit osteoclast differentiation induced by receptor activator of nuclear factor kappa-B ligand (RANKL). 8-Epixanthatin exhibited no significant cytotoxicity at the concentrations used for osteoclast differentiation studies. The compound showed concentration-dependent reductions in TRAP-positive multinucleated osteoclasts, with an IC50 value of 2.3 μM. Our mechanistic investigations revealed that 8-Epixanthatin interferes with RANKL-activated signaling networks, particularly nuclear factor kappa-B (NF-κB) and mitogen-activated protein kinase (MAPK) cascades. Collectively, these observations identify 8-Epixanthatin as a promising lead structure for anti-osteoclast drug discovery.