title: Neuropeptide FF inhibits LPS-mediated osteoclast differentiation of RAW264.7 cells.
abstract: Neuropeptide FF (NPFF) has been implicated in many physiological processes. Previously, we have reported that NPFF modulates the viability and nitric oxide (NO) production of RAW264.7 macrophages. In this study, we investigated the influence of NPFF on lipopolysaccharide (LPS)-mediated osteoclast formation of RAW264.7 cells. Our results suggest that, NPFF dose-dependently (1 nM, 10 nM and 100 nM) inhibited osteoclast formation, TRAP enzyme activity and bone resorption in osteoclasts induced by LPS respectively. Moreover, LPS-provoked NO release was also inhibited by NPFF treatment, indicating a NO-dependent pathway is mainly involved. Furthermore, the alterations of osteoclast marker genes were also assessed including TRAP, Cathepsin K, MMP-9, NFATc1 and Runx2. NPFF downregulated LPS-caused gene augmentations of TRAP, Cathepsin K and MMP-9, whereas showed no influences on NFATc1 and Runx2. In addition, NPFF receptor 2 (NPFFR2) mRNA expression was also augmented in response to NPFF treatment, hinting the involvement of NPFFR2 pathway. It should be mentioned that RF9 (1 µ M), a reported pharmacological inhibitor for NPFF receptors, exerted NPFF-like agonist properties as to attenuate osteoclastogenesis. Collectively, our findings provide new evidence for the in vitro activity of NPFF on osteoclasts, which may be helpful to extend the scope of NPFF functions.
authors.forename: Yu-Long
authors.initials: YL
authors.lastname: Sun
authors.forename: Zhi-Hao
authors.initials: ZH
authors.lastname: Chen
authors.forename: Di-Jie
authors.initials: DJ
authors.lastname: Li
authors.forename: Fan
authors.initials: F
authors.lastname: Zhao
authors.forename: Xiao-Li
authors.initials: XL
authors.lastname: Ma
authors.forename: Peng
authors.initials: P
authors.lastname: Shang
authors.forename: Tuanming
authors.initials: T
authors.lastname: Yang
authors.forename: Airong
authors.initials: A
authors.lastname: Qian
mesh_terms: D000135:Acid Phosphatase / Q000378:metabolism; D000218:Adamantane / Q000031:analogs & derivatives / Q000494:pharmacology; D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D004151:Dipeptides / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects; D066298:In Vitro Techniques; D007527:Isoenzymes / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008264:Macrophages / Q000166:cytology / Q000187:drug effects*; D051379:Mice; D009842:Oligopeptides / Q000819:agonists / Q000494:pharmacology*; D010010:Osteoclasts / Q000187:drug effects* / Q000378:metabolism; D018013:Receptors, Neuropeptide / Q000235:genetics*; D000071681:Tartrate-Resistant Acid Phosphatase; D015854:Up-Regulation
chemical_list: D004151:Dipeptides; D007527:Isoenzymes; D008070:Lipopolysaccharides; D009842:Oligopeptides; D018013:Receptors, Neuropeptide; C508361:adamantylcarbonyl-arginyl-phenylalaninamide; C083929:neuropeptide FF receptor; C053651:phenylalanyl-leucyl-phenylalanyl-glutaminyl-prolyl-glutaminyl-arginyl-phenylalaninamide; D000135:Acid Phosphatase; C000605511:Acp5 protein, mouse; D000071681:Tartrate-Resistant Acid Phosphatase; D000218:Adamantane