Clinical science (London, England : 1979)

Intact initiation of autophagy and mitochondrial fission by acute exercise in skeletal muscle of patients with Type 2 diabetes.

PMID 27837193


Type 2 diabetes (T2D) is characterized by insulin resistance, mitochondrial dysregulation and, in some studies, exercise resistance in skeletal muscle. Regulation of autophagy and mitochondrial dynamics during exercise and recovery is important for skeletal muscle homoeostasis, and these responses may be altered in T2D. We examined the effect of acute exercise on markers of autophagy and mitochondrial fusion and fission in skeletal muscle biopsies from patients with T2D (n=13) and weight-matched controls (n=14) before, immediately after and 3 h after an acute bout of exercise. Although mRNA levels of most markers of autophagy [PIK3C, MAP1LC3B, sequestosome 1 (SQSTM1), BCL-2/adenovirus E1B 19-kDa-interacting protein 3 (BNIP3), BNIP3-like (BNIP3L)] and mitochondrial dynamics [optic atrophy 1 (OPA1), fission protein 1 (FIS1)] remained unchanged, some either increased during and after exercise (GABARAPL1), decreased in the recovery period [BECN1, autophagy-related (ATG) 7, DNM1L] or both [mitofusin (MFN) 2, mitochondrial E3 ubiquitin ligase 1 (MUL1)]. Protein levels of ATG7, p62/SQSTM1, forkhead box O3A (FOXO3A) and MFN2 (only controls) as well as dynamin-related protein 1 (DRP1) Ser