title: Immobilization induces nuclear accumulation of HDAC4 in rat skeletal muscle.
abstract: The study described herein aimed to examine changes in HDAC4 and its downstream targets in immobilization-induced rat skeletal muscle atrophy. Eleven male Wistar rats were used, and one hindlimb was immobilized in the plantar flexion position using a plaster cast. The contralateral, non-immobilized leg served as an internal control. After 10 days, the gastrocnemius muscles were removed from both hindlimbs. Ten days of immobilization resulted in a significant reduction (-27.3 %) in gastrocnemius muscle weight. A significant decrease in AMPK phosphorylation was also observed in nuclear fractions from immobilized legs relative to the controls. HDAC4 expression was significantly increased in immobilized legs in both the cytoplasmic and nuclear fractions. Moreover, Myogenin and MyoD mRNA levels were upregulated in immobilized legs, resulting in increased Atrogin-1 mRNA expression. Our data suggest that nuclear HDAC4 accumulation is partly related to immobilization-induced muscle atrophy.
authors.affiliation: Graduate School of Health and Sports Science, Juntendo University, 1-1 Hirakagakuendai, Inzai, Chiba, 270-1695, Japan. t-yoshih@juntendo.ac.jp.
authors.forename: Toshinori
authors.initials: T
authors.lastname: Yoshihara
authors.affiliation: Graduate School of Health and Sports Science, Juntendo University, 1-1 Hirakagakuendai, Inzai, Chiba, 270-1695, Japan.
authors.forename: Shuichi
authors.initials: S
authors.lastname: Machida
authors.affiliation: Faculty of Human Ecology, Wayo Women's University, 2-3-1 konodai, Ichikawa, Chiba, 272-8533, Japan.
authors.forename: Yuka
authors.initials: Y
authors.lastname: Kurosaka
authors.affiliation: Faculty of Medicine, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Kakigi
authors.affiliation: Faculty of Education, Yamaguchi University, 1677-1 Yoshida, Yamaguchi, Yamaguchi, 753-8513, Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Sugiura
authors.affiliation: Graduate School of Health and Sports Science, Juntendo University, 1-1 Hirakagakuendai, Inzai, Chiba, 270-1695, Japan.
authors.forename: Hisashi
authors.initials: H
authors.lastname: Naito
mesh_terms: D000263:Adenylate Kinase / Q000378:metabolism; D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism*; D006655:Histone Deacetylases / Q000378:metabolism*; D007103:Immobilization; D008297:Male; D009124:Muscle Proteins / Q000378:metabolism; D018482:Muscle, Skeletal / Q000378:metabolism*; D009133:Muscular Atrophy / Q000378:metabolism*; D017570:MyoD Protein / Q000378:metabolism; D018008:Myogenin / Q000378:metabolism; D010766:Phosphorylation; D051381:Rats; D017208:Rats, Wistar; D044843:SKP Cullin F-Box Protein Ligases / Q000378:metabolism
chemical_list: D009124:Muscle Proteins; D017570:MyoD Protein; D018008:Myogenin; C486692:Fbxo32 protein, rat; D044843:SKP Cullin F-Box Protein Ligases; D000263:Adenylate Kinase; C559944:HDAC4 protein, rat; D006655:Histone Deacetylases
keywords: Disuse muscle atrophy; Histone deacetylase 4; Myogenic regulatory factors; Nuclear abundance