title: Ethanolic extract of Schizonepeta tenuifolia attenuates osteoclast formation and activation in vitro and protects against lipopolysaccharide-induced bone loss in vivo.
abstract: BACKGROUND
  Excessive osteoclast activity is a major cause of metabolic bone disorders, such as osteopenia, rheumatoid arthritis, and osteoporosis. Thus, discovery of agents targeting osteoclast differentiation and bone resorption is important for development of novel treatments for bone diseases. It has been demonstrated that ethanolic extract of schizonepeta tenuifolia (EEST) has potent anti-oxidant and anti-inflammatory activities. However, the beneficial effects of EEST on bone metabolism have not been studied. Therefore, we intend to investigate the effects of EEST on osteoclast differentiation.
  
  
  METHODS
  We examined the effects and mechanisms of action of the EEST on osteoclastogenesis in vitro in bone marrow macrophages (BMMs) stimulated with receptor activator of nuclear factor kappa-B ligand (RANKL) and in vivo using a mouse model of lipopolysaccharide (LPS)-induced bone destruction.
  
  
  RESULTS
  We found that EEST inhibited phosphorylation of Akt and IkB at early stages of RANKL-induced osteoclastogenesis. Furthermore, EEST negatively controlled the transcription and translation levels of nuclear factor of activated T cells c1 (NFATc1) and the translation level of c-Fos at the final stage of osteoclast differentiation. Reflecting these effects, EEST blocked both filamentous actin (F-actin) ring formation and bone resorbing activity of mature osteoclasts in vitro. The inhibitory effects of EEST on osteoclast formation and activity were observed in an LPS-mediated bone erosion mouse model using micro-CT and histological analysis.
  
  
  CONCLUSIONS
  EEST is a potential agent that is able to treat osteoclast-related bone diseases, such as osteoporosis.
authors.affiliation: Imaging Science-based Lung and Bone Diseases Research Center, Wonkwang University, Iksan, Jeonbuk, 570-749, Republic of Korea.|Institute for Skeletal Disease, Wonkwang University, Iksan, Jeonbuk, 570-749, Republic of Korea.|Institute for Environmental Science, Wonkwang University, Iksan, Jeonbuk, 570-749, Republic of Korea.
authors.forename: Ju-Young
authors.initials: JY
authors.lastname: Kim
authors.affiliation: Department of Anatomy, School of Medicine, Wonkwang University, 344-2 Sinyong-dong, Iksan, Jeonbuk, 570-749, Republic of Korea.
authors.forename: Jong Min
authors.initials: JM
authors.lastname: Baek
authors.affiliation: Department of Anatomy, School of Medicine, Wonkwang University, 344-2 Sinyong-dong, Iksan, Jeonbuk, 570-749, Republic of Korea.
authors.forename: Sung-Jun
authors.initials: SJ
authors.lastname: Ahn
authors.affiliation: Imaging Science-based Lung and Bone Diseases Research Center, Wonkwang University, Iksan, Jeonbuk, 570-749, Republic of Korea.|Department of Anatomy, School of Medicine, Wonkwang University, 344-2 Sinyong-dong, Iksan, Jeonbuk, 570-749, Republic of Korea.
authors.forename: Yoon-Hee
authors.initials: YH
authors.lastname: Cheon
authors.affiliation: Department of Anatomy, School of Medicine, Wonkwang University, 344-2 Sinyong-dong, Iksan, Jeonbuk, 570-749, Republic of Korea.
authors.forename: Sun-Hyang
authors.initials: SH
authors.lastname: Park
authors.affiliation: Institute for Environmental Science, Wonkwang University, Iksan, Jeonbuk, 570-749, Republic of Korea.|Department of Anatomy, School of Medicine, Wonkwang University, 344-2 Sinyong-dong, Iksan, Jeonbuk, 570-749, Republic of Korea.
authors.forename: Miyoung
authors.initials: M
authors.lastname: Yang
authors.affiliation: Institute for Environmental Science, Wonkwang University, Iksan, Jeonbuk, 570-749, Republic of Korea.|Department of Anatomy, School of Medicine, Wonkwang University, 344-2 Sinyong-dong, Iksan, Jeonbuk, 570-749, Republic of Korea.
authors.forename: Min Kyu
authors.initials: MK
authors.lastname: Choi
authors.affiliation: Imaging Science-based Lung and Bone Diseases Research Center, Wonkwang University, Iksan, Jeonbuk, 570-749, Republic of Korea. jmoh@wku.ac.kr.|Institute for Skeletal Disease, Wonkwang University, Iksan, Jeonbuk, 570-749, Republic of Korea. jmoh@wku.ac.kr.|Department of Anatomy, School of Medicine, Wonkwang University, 344-2 Sinyong-dong, Iksan, Jeonbuk, 570-749, Republic of Korea. jmoh@wku.ac.kr.
authors.forename: Jaemin
authors.identifier: http://orcid.org/0000-0002-1040-4872
authors.initials: J
authors.lastname: Oh
mesh_terms: D000818:Animals; D001862:Bone Resorption / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects*; D019686:Lamiaceae / Q000737:chemistry*; D008070:Lipopolysaccharides; D000432:Methanol; D051379:Mice; D008813:Mice, Inbred ICR; D010010:Osteoclasts / Q000187:drug effects*; D010024:Osteoporosis; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D020011:Protective Agents / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D008070:Lipopolysaccharides; D010936:Plant Extracts; D020011:Protective Agents; D000432:Methanol
keywords: Bone resorption; Osteoclast differentiation; Osteoporosis; Schizonepeta tenuifolia