title: "Hybrid exercise" prevents muscle atrophy in association with a distinct gene expression pattern.
abstract: "Hybrid exercise" utilizing combined electrical stimulation and voluntary muscle contraction has been developed as a muscle exercise method. Although our previous studies have confirmed the effectiveness of the procedure, the mechanisms of its efficacy still remain unclear. In the present study, we identified genes that are specifically expressed in disused muscles, using the semitendinosus muscle from patients who underwent anterior cruciate ligament (ACL) reconstruction. Preoperative exercise was performed by four ACL-injured patients, who were subjected either to hybrid exercise (n=2), electrical stimulation (n=1), or no electrical stimulation (n=1), in addition to standard weight training for 4 weeks. Cross-sectional area (CSA) of the semitendinosus muscle was measured before and after the exercise by magnetic resonance imaging (MRI). A piece of the semitendinosus muscle was isolated during the surgery, and comprehensive analysis of the gene expression in this sample was performed using DNA microarray analysis. CSA increased in size by 4.2 and 14.7%, respectively, after hybrid exercise, and by 1.4% after electrical stimulation. However it shrunk by 7.7% without electrical stimulation. DNA microarray analysis revealed that hybrid exercise was more effective at stimulating the expression of signal transduction-, transcription- and cytoskeleton-related genes in semitendinosus muscles than electrical stimulation alone. In particular, gene ontology analysis revealed that hybrid exercise induced significantly higher expression of eukaryotic translation initiation factor 5A (EIFSA), peroxisomal biogenesis factor 6 (PEX6) and histone cluster 1 H4 (HIST1H4), compared with electrical stimulation alone. The expression of signal transduction-, transcription- and cytoskeleton-related genes may play an important role in muscle bulk increasing mechanisms in hybrid exercise.
authors.affiliation: Department of Orthopedics, Kurume University School of Medicine, Japan. nshiba@med.kurume-u.ac.jp
authors.forename: Toru
authors.initials: T
authors.lastname: Matsugaki
authors.forename: Naoto
authors.initials: N
authors.lastname: Shiba
authors.forename: Shohei
authors.initials: S
authors.lastname: Kohno
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nikawa
authors.forename: Katsuya
authors.initials: K
authors.lastname: Hirasaka
authors.forename: Yuushi
authors.initials: Y
authors.lastname: Okumura
authors.forename: Kazumi
authors.initials: K
authors.lastname: Ishidoh
authors.forename: Takashi
authors.initials: T
authors.lastname: Soejima
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Yoshimitsu
authors.forename: Kensei
authors.initials: K
authors.lastname: Nagata
mesh_terms: D000074183:ATPases Associated with Diverse Cellular Activities; D000251:Adenosine Triphosphatases / Q000235:genetics; D000293:Adolescent; D000328:Adult; D016118:Anterior Cruciate Ligament / Q000473:pathology; D004599:Electric Stimulation Therapy; D015444:Exercise; D005260:Female; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006657:Histones / Q000235:genetics; D006801:Humans; D007718:Knee Injuries / Q000601:surgery*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009119:Muscle Contraction; D009133:Muscular Atrophy / Q000473:pathology*; D020411:Oligonucleotide Array Sequence Analysis; D010448:Peptide Initiation Factors / Q000235:genetics; D016601:RNA-Binding Proteins / Q000235:genetics; D055815:Young Adult; D000097574:Eukaryotic Translation Initiation Factor 5A
chemical_list: D000074183:ATPases Associated with Diverse Cellular Activities; D000251:Adenosine Triphosphatases; D006657:Histones; D010448:Peptide Initiation Factors; D016601:RNA-Binding Proteins; D000097574:Eukaryotic Translation Initiation Factor 5A; C490759:PEX6 protein, human