ZFIN ID: ZDB-PUB-200225-32
AMPK Complex Activation Promotes Sarcolemmal Repair in Dysferlinopathy
Ono, H., Suzuki, N., Kanno, S.I., Kawahara, G., Izumi, R., Takahashi, T., Kitajima, Y., Osana, S., Nakamura, N., Akiyama, T., Ikeda, K., Shijo, T., Mitsuzawa, S., Nagatomi, R., Araki, N., Yasui, A., Warita, H., Hayashi, Y.K., Miyake, K., Aoki, M.
Date: 2020
Source: Molecular therapy : the journal of the American Society of Gene Therapy   28(4): 1133-1153 (Journal)
Registered Authors: Kawahara, Genri
Keywords: AMPK, dysferlin, membrane repair, mouse model, muscular dystrophy, zebrafish
MeSH Terms:
  • AMP-Activated Protein Kinases/metabolism*
  • Animals
  • Cell Line
  • Disease Models, Animal
  • Dysferlin/chemistry*
  • Dysferlin/genetics
  • Dysferlin/metabolism*
  • Humans
  • Lasers/adverse effects
  • Metformin/administration & dosage*
  • Metformin/pharmacology
  • Mice
  • Muscle, Skeletal/injuries*
  • Muscle, Skeletal/metabolism
  • Muscular Dystrophies, Limb-Girdle/drug therapy*
  • Muscular Dystrophies, Limb-Girdle/genetics
  • Muscular Dystrophies, Limb-Girdle/metabolism
  • Mutation
  • Phosphorylation
  • Protein Domains
  • Sarcolemma/metabolism
  • Zebrafish
PubMed: 32087766 Full text @ Mol. Ther.
Mutations in dysferlin are responsible for a group of progressive, recessively inherited muscular dystrophies known as dysferlinopathies. Using recombinant proteins and affinity purification methods combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS), we found that AMP-activated protein kinase (AMPK)γ1 was bound to a region of dysferlin located between the third and fourth C2 domains. Using ex vivo laser injury experiments, we demonstrated that the AMPK complex was vital for the sarcolemmal damage repair of skeletal muscle fibers. Injury-induced AMPK complex accumulation was dependent on the presence of Ca2+, and the rate of accumulation was regulated by dysferlin. Furthermore, it was found that the phosphorylation of AMPKα was essential for plasma membrane repair, and treatment with an AMPK activator rescued the membrane-repair impairment observed in immortalized human myotubes with reduced expression of dysferlin and dysferlin-null mouse fibers. Finally, it was determined that treatment with the AMPK activator metformin improved the muscle phenotype in zebrafish and mouse models of dysferlin deficiency. These findings indicate that the AMPK complex is essential for plasma membrane repair and is a potential therapeutic target for dysferlinopathy.