Supplemental Table 1 for "Leucine supplementation augments skeletal muscle mitochondrial respiration during recovery following 7 days of physical inactivity in older adults"

Mitochondrial respiration measures determined using OroBors high resolution respirometry Protocol 1. Since all OroBoros measurements originate from the same muscle biopsy sample, these are presented as technical replicates (with the exception of State 4_o). All outcomes have units of (pmol O₂/sec/mg tissue).

Supplemental Table supporting:
"Leucine supplementation augments skeletal muscle mitochondrial respiration during recovery following 7 days of physical inactivity in older adults"

Emily J. Arentson-Lantz, Jasmine Mikovic, Nisha Bhattarai, Christopher S. Fry, Severine Lamone, and Doug Paddon-Jones

In older adults, leucine supplementation attenuates the loss of skeletal muscle mass and function during bed rest. We sought to determine if leucine could also preserve and/or restore mitochondrial function and muscle oxidative capacity during periods of disuse and rehabilitation. Healthy older adults (69.1 ±1.1 years) consumed a structured diet with supplemental leucine (LEU: 0.06 g/ kg body weight/ meal; n=8) or alanine (CON: 0.06 g/ kg body weight/meal; n=8) during 7 days of bed rest and 5 days of inpatient rehabilitation. A 75 g oral glucose tolerance test was performed at baseline (PreBR), after bed rest (PostBR) and rehabilitation (PostRehab) and used to calculate an indicator of insulin sensitivity, metabolic clearance rate. (MCR). Tissue samples from the m. vastus lateralis were collected PreBR, PostBR, and PostRehab to assess mitochondrial respiratory capacity and protein markers of the oxidative phosphorylation and a marker of the antioxidant defense systems. During bed rest, leucine tended to preserve insulin sensitivity (Change in MCR, CON vs. LEU: -3.5 ± 0.82 vs LEU: -0.98 ± 0.88, p=0.054), but had no effect on mitochondrial respiratory capacity (Change in State 3_+succinate CON vs. LEU -3.3 ± 6.1 vs. 7.3 ± 4.1 pmol O₂/sec/mg tissue, p=0.19) Following rehabilitation, leucine increased ATP-linked respiration (CON vs. LEU: -8.9 ± 6.2 vs. 18.8 ± 3.7 pmol O₂/sec/mg tissue, p=0.014). While the expression of mitochondrial respiratory and antioxidant proteins was not impacted, leucine supplementation preserved specific pathways of mitochondrial respiration, insulin sensitivity and a marker of oxidative stress during bed rest and rehabilitation.