Glycitein decreases the generation of murine osteoclasts and increases apoptosis.
BACKGROUND
Phytoestrogens, especially genistein, have been shown to have bone beneficial effects in vitro and in vivo. However, the effect of glycitein on bone cells is not known. The aim of this study was to investigate the effects of glycitein on osteoclast differentiation and apoptosis in vitro.


METHODS
Bone marrow-derived osteoclasts were cultured with various concentrations (0.01-100 nM) of glycitein. Osteoclast generation was assessed by the number of multinucleated, tartrate-resistant acid phosphatase (TRAP)-positive cells, and apoptosis by the activity of caspase 3/7. Bone-marrow-derived osteoblasts were cultured in the presence of 10 nM glycitein. Subsequently, gene expression levels of receptor activator of NFκB ligand (RANKL), osteoprotegerin (OPG), and interleukin-6 (IL-6) were determined by real-time PCR.


RESULTS
Osteoclast generation was inhibited by glycitein in a biphasic-dose-dependent manner and showed the greatest inhibitory effects at 10 nM (-70%, p < 0.01). Glycitein increased caspase 3/7 activity by 15% at a concentration of 10 nM (p < 0.001). Further, 10 nM glycitein significantly decreased the expression of IL-6 (-53%, p < 0.05) and RANKL (-64%, p < 0.05) in osteoblasts but did not change mRNA levels of OPG.


CONCLUSIONS
Our data demonstrate that glycitein suppresses osteoclast generation and induces osteoclast apoptosis in vitro to a similar extent as genistein and therefore suggests that glycitein may also exert bone beneficial effects in vivo.
Winzer
Maria
M
Department of Pathophysiology, Medical University of Vienna, Vienna, Austria.
Rauner
Martina
M
Pietschmann
Peter
P
D000818:Animals; D017209:Apoptosis / Q000187:drug effects* / Q000235:genetics; D002454:Cell Differentiation / Q000187:drug effects* / Q000235:genetics; D004305:Dose-Response Relationship, Drug; D005786:Gene Expression Regulation / Q000187:drug effects / Q000235:genetics; D066298:In Vitro Techniques; D015850:Interleukin-6 / Q000235:genetics; D007529:Isoflavones / Q000494:pharmacology*; D051379:Mice; D010010:Osteoclasts / Q000187:drug effects*; D053244:Osteoprotegerin / Q000235:genetics; D048789:Phytoestrogens / Q000494:pharmacology*; D053245:RANK Ligand / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction
D015850:Interleukin-6; D007529:Isoflavones; D053244:Osteoprotegerin; D048789:Phytoestrogens; D053245:RANK Ligand; D012333:RNA, Messenger; C505689:Tnfsf11 protein, mouse; C086566:glycitein