title: (-)-Epigallocatechin gallate inhibition of osteoclastic differentiation via NF-kappaB.
abstract: People who regularly drink tea have been found to have a higher bone mineral density (BMD) and to be at less risk of hip fractures than those who do not drink it. Green tea catechins such as (-)-epigallocatechin gallate (EGCG) have been reported to increase osteogenic functioning in mesenchymal stem cells. However, its effect on osteoclastogenesis remains unclear. In this study, we investigated the effect of EGCG on RANKL-activation osteoclastogenesis and NF-kappaB in RAW 264.7, a murine preosteoclast cell line. EGCG (10-100 microM) significantly suppressed the RANKL-induced differentiation of osteoclasts and the formation of pits in murine RAW 264.7 cells and bone marrow macrophages (BMMs). EGCG appeared to target osteoclastic differentiation at an early stage but had no cytotoxic effect on osteoclast precursors. In addition, it significantly inhibited RANKL-induced NF-kappaB transcriptional activity and nuclear translocation. We conclude that EGCG inhibits osteoclastogenesis through its activation of NF-kappaB.
authors.affiliation: Graduate Institute of Pharmaceutical Sciences, College of Pharmacy, Kaohsiung Medical University, No. 100 Shih-Chuan 1st Road, 807 Kaohsiung, Taiwan, ROC.
authors.forename: Ru-Wei
authors.initials: RW
authors.lastname: Lin
authors.forename: Chung-Hwan
authors.initials: CH
authors.lastname: Chen
authors.forename: Yan-Hsiung
authors.initials: YH
authors.lastname: Wang
authors.forename: Mei-Ling
authors.initials: ML
authors.lastname: Ho
authors.forename: Shao-Hung
authors.initials: SH
authors.lastname: Hung
authors.forename: Ih-Sheng
authors.initials: IS
authors.lastname: Chen
authors.forename: Gwo-Jaw
authors.initials: GJ
authors.lastname: Wang
mesh_terms: D021581:Active Transport, Cell Nucleus / Q000187:drug effects; D000818:Animals; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology; D002454:Cell Differentiation / Q000187:drug effects*; D002460:Cell Line; D051379:Mice; D016328:NF-kappa B / Q000378:metabolism*; D010010:Osteoclasts / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D053245:RANK Ligand / Q000494:pharmacology; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: D016328:NF-kappa B; D053245:RANK Ligand; C505689:Tnfsf11 protein, mouse; D002392:Catechin; C045651:epigallocatechin gallate