1. MOTS-c reduces myostatin and muscle atrophy signaling.
- Author
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Kumagai H, Coelho AR, Wan J, Mehta HH, Yen K, Huang A, Zempo H, Fuku N, Maeda S, Oliveira PJ, Cohen P, and Kim SJ
- Subjects
- Adult, Aged, Aged, 80 and over, Animals, Cells, Cultured, Diet, High-Fat, Humans, Male, Mice, Mice, Inbred C57BL, Middle Aged, Mitochondrial Proteins blood, Muscle, Skeletal metabolism, Muscle, Skeletal pathology, Muscular Atrophy blood, Muscular Atrophy etiology, Myostatin metabolism, Palmitic Acid, Signal Transduction physiology, Young Adult, Mitochondrial Proteins physiology, Muscular Atrophy metabolism, Myostatin blood, Myostatin physiology
- Abstract
Obesity and type 2 diabetes are metabolic diseases, often associated with sarcopenia and muscle dysfunction. MOTS-c, a mitochondrial-derived peptide, acts as a systemic hormone and has been implicated in metabolic homeostasis. Although MOTS-c improves insulin sensitivity in skeletal muscle, whether MOTS-c impacts muscle atrophy is not known. Myostatin is a negative regulator of skeletal muscle mass and also one of the possible mediators of insulin resistance-induced skeletal muscle wasting. Interestingly, we found that plasma MOTS-c levels are inversely correlated with myostatin levels in human subjects. We further demonstrated that MOTS-c prevents palmitic acid-induced atrophy in differentiated C2C12 myotubes, whereas MOTS-c administration decreased myostatin levels in plasma in diet-induced obese mice. By elevating AKT phosphorylation, MOTS-c inhibits the activity of an upstream transcription factor for myostatin and other muscle wasting genes, FOXO1. MOTS-c increases mTORC2 and inhibits PTEN activity, which modulates AKT phosphorylation. Further upstream, MOTS-c increases CK2 activity, which leads to PTEN inhibition. These results suggest that through inhibition of myostatin, MOTS-c could be a potential therapy for insulin resistance-induced skeletal muscle atrophy as well as other muscle wasting phenotypes including sarcopenia. NEW & NOTEWORTHY MOTS-c, a mitochondrial-derived peptide reduces high-fat-diet-induced muscle atrophy signaling by reducing myostatin expression. The CK2-PTEN-mTORC2-AKT-FOXO1 pathways play key roles in MOTS-c action on myostatin expression.
- Published
- 2021
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