Randomized trial shows MitoQ improves skeletal muscle OXPHOS in younger adults, suggesting a focus on respiratory capacity.
Key Points
To determine how age and basal respiratory capacity influence the effect of MitoQ on skeletal muscle OXPHOS.
Twenty-one younger adults (26 ± 6 years) and twenty older adults (66 ± 7 years) received either MitoQ (40 mg/day) or placebo for 2 weeks.
Skeletal muscle biopsies were performed to measure mitochondrial respiration and protein expression before and after supplementation.
High-resolution respirometry assessed mitochondrial respiration, while Western blots evaluated protein expression.
Older adults had higher state 4 respiration compared to younger adults (p < 0.001), but no group differences in state 3 OXPHOS were found (p > 0.05).
MitoQ significantly improved state 3 respiration in younger adults, with higher rates observed (e.g., state 3 CI: Pre: 11.27 vs Post: 15.82 pmol·s-1·mg-1, p < 0.05).
Baseline state 3 CI+II OXPHOS was negatively correlated with the change in CI+II OXPHOS with MitoQ supplementation (r = -0.76, p = 0.010) in older adults.