The effect of repeated bouts of electrical stimulation‐induced muscle contractions on proteolytic signaling in rat skeletal muscle

Autor: Takaya Kotani, Koichi Nakazato, Yuki Tamura, Junya Takegaki, Karina Kouzaki, Naokata Ishii
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Male
muscle protein breakdown
Physiology
Muscle Proteins
Stimulation
mTORC1
030204 cardiovascular system & hematology
Rats
Sprague-Dawley

0302 clinical medicine
LC3
QP1-981
Ribosomal Protein S6
biology
Chemistry
Ribosomal Protein S6 Kinases
70-kDa

Calpain
Isoenzymes
medicine.anatomical_structure
Phosphorylation
Original Article
calpain
Microtubule-Associated Proteins
Muscle Contraction
Signal Transduction
medicine.medical_specialty
Mechanistic Target of Rapamycin Complex 1
03 medical and health sciences
Ubiquitinated Proteins
P70S6 kinase
Physiology (medical)
Internal medicine
Physical Conditioning
Animal

medicine
Animals
Muscle
Skeletal

Resistance training
Autophagosomes
Ubiquitination
Skeletal muscle
Original Articles
ubiquitinated protein
Electric Stimulation
Rats
Endocrinology
resistance exercise
Proteolysis
biology.protein
human activities
030217 neurology & neurosurgery
Zdroj: Physiological Reports, Vol 9, Iss 9, Pp n/a-n/a (2021)
Physiological Reports
Popis: Mechanistic target of rapamycin complex 1 (mTORC1) plays a central role in muscle protein synthesis and repeated bouts of resistance exercise (RE) blunt mTORC1 activation. However, the changes in the proteolytic signaling when recurrent RE bouts attenuate mTORC1 activation are unclear. Using a RE model of electrically stimulated rat skeletal muscle, this study aimed to clarify the effect of repeated RE bouts on acute proteolytic signaling, particularly the calpain, autophagy‐lysosome, and ubiquitin‐proteasome pathway. p70S6K and rpS6 phosphorylation, indicators of mTORC1 activity, were attenuated by repeated RE bouts. Calpain 3 protein was decreased at 6 h post‐RE in all exercised groups regardless of the bout number. Microtubule‐associated protein 1 light chain 3 beta‐II, an indicator of autophagosome formation, was increased at 3 h and repeated RE bouts increased at 6 h, post‐RE. Ubiquitinated proteins were increased following RE, but these increases were independent of the number of RE bouts. These results suggest that the magnitude of autophagosome formation was increased following RE when mTORC1 activity was attenuated with repeated bouts of RE.
Repeated bouts of resistance exercise (RE) attenuate the degree of exercise‐induced mechanistic target of rapamycin complex 1 (mTORC1) activation in skeletal muscle. The present study suggests that repeated bouts of RE increased light chain 3 beta (LC3)‐II protein (an indicator of autophagosome formation) following RE when mTORC1 activation was attenuated with repeated bouts of RE in rat skeletal muscle.
Databáze: OpenAIRE