N16 suppresses RANKL-mediated osteoclatogenesis by down-regulating RANK expression

N16 is an active protein existing in Pinclada martensi.Our previous studies have demonstrated that N16 inhibited osteoclast differentiation in vitro. To better understand how N16 regulates osteoclast differentiation, RAW264.7 cells, a murinc monotylic cell line and murine bone marrow-derived macrophages ( BM Ms) were adopted. Treatment of RAW264.7 cells with RANKL activated osteoclastogenesis and N16 inhibited the formation of multinudeatal osteoclasts and TRAP activity. The suppression occurred at the early stage of osteoclastogenesis. Moreover, we found that N16 inhibited PU.1 and M RV expressions, mirroring the inhibition of RANK expressions, indicating that N16 inhibited RANK expression by down-regulating the expressions of MITE and PU.1, thus preventing osteoclastogenesis. (C) 2019 Elsevier B.V. All rights reserved.