The mitochondrial mRNA-stabilizing protein SLIRP regulates skeletal muscle mitochondrial structure and respiration by exercise-recoverable mechanisms.

Decline in mitochondrial function is linked to decreased muscle mass and strength in conditions like sarcopenia and type 2 diabetes. Despite therapeutic opportunities, there is limited and equivocal data regarding molecular cues controlling muscle mitochondrial plasticity. Here we uncovered that the mitochondrial mRNA-stabilizing protein SLIRP, in complex with LRPPRC, is a PGC-1α target that regulates mitochondrial structure, respiration, and mtDNA-encoded-mRNA pools in skeletal muscle.

High-Intensity Training Represses FXYD5 and Glycosylates Na,K-ATPase in Type II Muscle Fibres, Which Are Linked with Improved Muscle K Handling and Performance.

Na/K ATPase (NKA) comprises several subunits to provide isozyme heterogeneity in a tissue-specific manner. An abundance of NKA α, β, and FXYD1 subunits is well-described in human skeletal muscle, but not much is known about FXYD5 (dysadherin), a regulator of NKA and β1 subunit glycosylation, especially with regard to fibre-type specificity and influence of sex and exercise training. Here, we investigated muscle fibre-type specific adaptations in FXYD5 and glycosylated NKAβ1 to high-intensity interval training (HIIT), as well as sex differences in FXYD5 abundance.

High-Intensity Exercise Training Alters the Effect of -Acetylcysteine on Exercise-Related Muscle Ionic Shifts in Men.

This study investigated whether high-intensity exercise training alters the effect of -acetylcysteine (a precursor of antioxidant glutathione) on exercise-related muscle ionic shifts. We assigned 20 recreationally-active men to 6 weeks of high-intensity exercise training, comprising three weekly sessions of 4-10 × 20-s all-out bouts interspersed by 2 min recovery (SET, n = 10), or habitual lifestyle maintenance (n = 10). Before and after SET, we measured ionic shifts across the working muscle, using leg arteriovenous balance technique, during one-legged knee-extensor exercise to exhaustion with and without -acetylcysteine infusion.

High-intensity interval training remodels the proteome and acetylome of human skeletal muscle.

Exercise is an effective strategy in the prevention and treatment of metabolic diseases. Alterations in the skeletal muscle proteome, including post-translational modifications, regulate its metabolic adaptations to exercise. Here, we examined the effect of high-intensity interval training (HIIT) on the proteome and acetylome of human skeletal muscle, revealing the response of 3168 proteins and 1263 lysine acetyl-sites on 464 acetylated proteins.

Anabolic and lipolytic actions of beta -agonists in humans and antidoping challenges.

Inhaled beta -adrenoceptor agonists (beta -agonists) are among the most used substances in competitive sports. The 2020 Prohibited List issued by the World Anti-Doping Agency restricts use of all selective and non-selective beta -agonists in- and out- of competition with few exemptions. Formoterol, salbutamol, and salmeterol are allowed by inhalation within defined dosing limits.

Effect of beta -adrenergic agonist and resistance training on maximal oxygen uptake and muscle oxidative enzymes in men.

While beta -adrenoceptor stimulation has been shown to increase lean mass and to alter metabolic properties of skeletal muscle, adaptations in muscle oxidative enzymes and maximal oxygen uptake ( O ) in response to beta -adrenergic agonist treatment are inadequately explored in humans, particularly in association with resistance training. Herein, we investigated beta -adrenergic-induced changes in O , leg and arm composition, and muscle content of oxidative enzymes in response to treatment with the selective beta -adrenergic agonist terbutaline with and without concurrent resistance training in young men. Forty-six subjects were randomized to 4 weeks of lifestyle maintenance (n = 23) or resistance training (n = 23).