CTSK and osteoporosis: Alisol A 24-acetate inhibited RANKL-induced osteoclast differentiation by downregulating NFATc1, a master factor for osteoclast differentiation, without cytotoxicity and also inhibited the expression of DC-STAMP and cathepsin K. Therefore, alisol A 24-acetate could be used as a scaffold for the development of a new osteoporosis drug.