Y1693 is an orally active RANKL inhibitor with a Kd of 5.03 μM for hRANKL. Y1693 inhibits the activation of the downstream c-fos/NFATc1 signaling pathway by blocking its interaction with RANK. Y1693 significantly inhibits RANKL-induced osteoclast differentiation, F-actin ring formation and bone resorptive activity, while downregulating the mRNA and protein expressions of TRAP, cathepsin K, c-fos and NFATc1. Y1693 shows no obvious cytotoxicity to bone marrow-derived macrophages and osteoclast precursor cells, and exhibits favorable ADME properties. Y1693 improves ovariectomy-induced osteoporosis in mice and reverses ligation-induced periodontal alveolar bone loss. Y1693 is applicable to research related to osteoporosis and periodontal diseases.
