title: A novel in vitro model of sarcopenia using BubR1 hypomorphic C2C12 myoblasts.
abstract: Sarcopenia is the age-related loss of skeletal muscle mass and function with adverse outcomes that include physical disability, poor quality of life, and death. The detailed molecular mechanisms remain unknown. An in vitro muscle atrophy model is needed to enable mechanistic studies. To create such a model, we employed BubR1 insufficiency which causes premature ageing in mice. Using C2C12 cells, a recognized in vitro model of the skeletal muscle cell, we obtained the BubR1 hypomorphic C2C12 (C2C12BKD) cells by using shRNA. The resulting C2C12BKD cells displayed several characteristics of the sarcopenic muscle cell. In C2C12BKD cells, formation of myotubes, assessed by analysis of fusion index, was markedly reduced as was the expression of myogenin and MyoD, two marker genes for myogenesis. Moreover, the cells showed increased expression of the muscle-specific ubiquitin ligases Atrogin-1 and MuRF-1, indicating increased protein degradation through the ubiquitin-proteasome dependent proteolytic pathway. These results suggest that C2C12BKD cells are potentially useful as a novel in vitro model of sarcopenia.
authors.affiliation: Department of Biochemistry and Applied Biosciences, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuen Kibanadai-nishi, Miyazaki, 889-2192, Japan.
authors.forename: Takateru
authors.initials: T
authors.lastname: Nozaki
authors.affiliation: Department of Biochemistry and Applied Biosciences, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuen Kibanadai-nishi, Miyazaki, 889-2192, Japan.
authors.forename: Shiori
authors.initials: S
authors.lastname: Nikai
authors.affiliation: Department of Biochemistry and Applied Biosciences, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuen Kibanadai-nishi, Miyazaki, 889-2192, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Okabe
authors.affiliation: Interdisciplinary Graduate School of Agriculture and Engineering, University of Miyazaki, 1-1 Gakuen Kibanadai-nishi, Miyazaki, 889-2192, Japan.
authors.forename: Kiyoko
authors.initials: K
authors.lastname: Nagahama
authors.affiliation: Department of Biochemistry and Applied Biosciences, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuen Kibanadai-nishi, Miyazaki, 889-2192, Japan. neto@cc.miyazaki-u.ac.jp.|Interdisciplinary Graduate School of Agriculture and Engineering, University of Miyazaki, 1-1 Gakuen Kibanadai-nishi, Miyazaki, 889-2192, Japan. neto@cc.miyazaki-u.ac.jp.
authors.forename: Nozomu
authors.initials: N
authors.lastname: Eto
keywords: BubR1 hypomorphic C2C12; Muscle-specific ubiquitin ligases; Myogenic differentiation; Sarcopenia