A single bout of resistance exercise triggers mitophagy, potentially involving the ejection of mitochondria in human skeletal muscle.
Acta Physiol (Oxf)
; 240(9): e14203, 2024 Sep.
Article
em En
| MEDLINE
| ID: mdl-39023008
ABSTRACT
AIM:
The present study aimed to investigate the effects of a single bout of resistance exercise on mitophagy in human skeletal muscle (SkM).METHODS:
Eight healthy men were recruited to complete an acute bout of one-leg resistance exercise. SkM biopsies were obtained one hour after exercise in the resting leg (Rest-leg) and the contracting leg (Ex-leg). Mitophagy was assessed using protein-related abundance, transmission electron microscopy (TEM), and fluorescence microscopy.RESULTS:
Our results show that acute resistance exercise increased pro-fission protein phosphorylation (DRP1Ser616) and decreased mitophagy markers such as PARKIN and BNIP3L/NIX protein abundance in the Ex-leg. Additionally, mitochondrial complex IV decreased in the Ex-leg when compared to the Rest-leg. In the Ex-leg, TEM and immunofluorescence images showed mitochondrial cristae abnormalities, a mitochondrial fission phenotype, and increased mitophagosome-like structures in both subsarcolemmal and intermyofibrillar mitochondria. We also observed increased mitophagosome-like structures on the subsarcolemmal cleft and mitochondria in the extracellular space of SkM in the Ex-leg. We stimulated human primary myotubes with CCCP, which mimics mitophagy induction in the Ex-leg, and found that BNIP3L/NIX protein abundance decreased independently of lysosomal degradation. Finally, in another human cohort, we found a negative association between BNIP3L/NIX protein abundance with both mitophagosome-like structures and mitochondrial cristae density in the SkM.CONCLUSION:
The findings suggest that a single bout of resistance exercise can initiate mitophagy, potentially involving mitochondrial ejection, in human skeletal muscle. BNIP3L/NIX is proposed as a sensitive marker for assessing mitophagy flux in SkM.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Músculo Esquelético
/
Mitofagia
Limite:
Adult
/
Humans
/
Male
Idioma:
En
Revista:
Acta Physiol (Oxf)
Assunto da revista:
FISIOLOGIA
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
Chile