Akt1 deficiency does not affect fiber type composition or mitochondrial protein expression in skeletal muscle of male mice

• Published in: Physiological reports Vol. 12; no. 17; pp. e70048 - n/a
• Main Authors: Miyaji, Tatsuya, Kasuya, Ryuichi, Sawada, Atsushi, Sawamura, Daisuke, Kitaoka, Yu, Miyazaki, Mitsunori
• Format: Journal Article
• Language: English
• Published: United States John Wiley & Sons, Inc 01.09.2024; John Wiley and Sons Inc; Wiley
• Subjects: AKT protein; Akt1; AKT1 protein; Animals; Antibodies; ATP Citrate (pro-S)-Lyase - deficiency; ATP Citrate (pro-S)-Lyase - genetics; ATP Citrate (pro-S)-Lyase - metabolism; ATP citrate lyase; Body weight; Cell growth; Enzymes; Glucose; glycolysis; Immunohistochemistry; Insulin; Kinases; Laboratories; Localization; Male; Metabolism; Mice; Mice, Inbred C57BL; Mice, Knockout; Mitochondria; Mitochondria, Muscle - metabolism; Mitochondrial Proteins - deficiency; Mitochondrial Proteins - genetics; Mitochondrial Proteins - metabolism; Muscle Fibers, Skeletal - metabolism; Muscle, Skeletal - metabolism; Musculoskeletal system; Original; Oxidative phosphorylation; Phosphorylation; Protein composition; Protein deficiency; Proteins; Proto-Oncogene Proteins c-akt - genetics; Proto-Oncogene Proteins c-akt - metabolism; Regular Manuscript; Skeletal muscle; United States > US; Japan; Germany; Akt1; skeletal muscle; mitochondria; glycolysis
• ISSN: 2051-817X; 2051-817X
• DOI: 10.14814/phy2.70048

Insulin‐like growth factor‐1‐induced activation of ATP citrate lyase (ACLY) improves muscle mitochondrial function through an Akt‐dependent mechanism. In this study, we examined whether Akt1 deficiency alters skeletal muscle fiber type and mitochondrial function by regulating ACLY‐dependent signaling in male Akt1 knockout (KO) mice (12–16 weeks old). Akt1 KO mice exhibited decreased body weight and muscle wet weight, with reduced cross‐sectional areas of slow‐ and fast‐type muscle fibers. Loss of Akt1 did not affect the phosphorylation status of ACLY in skeletal muscle. The skeletal muscle fiber type and expression of mitochondrial oxidative phosphorylation complex proteins were unchanged in Akt1 KO mice compared with the wild‐type control. These observations indicate that Akt1 is important for the regulation of skeletal muscle fiber size, whereas the regulation of muscle fiber type and muscle mitochondrial content occurs independently of Akt1 activity.