This finding was confirmed by a study that found that the expression of RANKL‐induced NFATc1 was abrogated in c‐Fos knockout mice.45 In addition, another study demonstrated that mice developed osteopetrosis because of c‐Fos deficiency, which also demonstrated the importance of c‐Fos in RANKL‐induced osteoclastogenesis.46 In our study, the activities of NFATc1, c‐Fos and Ca2+ oscillation were all inhibited by astilbin. The gene discussed is NFATC1; the disease is osteopetrosis.