Dynamic Proteome Profiling of the Human Muscle Response to Resistance Exercise Training
Authors: Burniston Jatin G , Camera Donny M , Pogson Mark A , Hawley John A 
Published: November 2023

Resistance exercise is a potent stimulus for muscle adaptation that is underpinned by selective changes in protein abundance. Our objective was to use Dynamic Proteome Profiling to calculate the contributions of synthesis and degradation to changes in abundance on a protein by protein basis. After 3 days of dietary control (65% Carbohydrate, 20% Fat, 15% Protein), two groups (n=8, in each) of age‐matched (37 ± 5 y old), overweight (BMI: 26 ± 3), untrained (38 ± 6

VO2max ml/kg/min) males consumed a high‐fat diet (20% Carbohydrate, 65% Fat, 15% Protein) and ingested deuterium oxide (200 ml/d) during a 9‐day intervention period. Venous blood samples were collected daily and samples of vastus lateralis were collected prior to (i.e. day 0 control) and on days 3, 6 and 9 of the intervention. Participants were assigned either to a non‐exercise group or an exercise group that performed resistance training (leg press, leg extension and dumbbell squats; each 4 × 10 repetitions at 80%1RM) on days 1, 4 and 7. Blood and muscle samples were analysed by mass spectrometry to determine precursor enrichment and the rate of incorporation of deuterium in to newly synthesised proteins. The relative abundance of each protein was analysed by label‐free profiling and the contribution of protein degradation was then calculated. Precursor (body water) enrichment increased at a rate of 0.14 ± 0.05 %/d and reached 2.14 ± 0.08 % after 9 days. Muscles were analysed as myofibrillar or sarcoplasmic fractions. The average rate of synthesis of mixed sarcoplasmic proteins was similar in control (2.05 ± %/d) and (2.19 ± %/d) exercised muscle. In the myofibrillar fraction, the average rate of synthesis was 45 % greater (P<0.05) in exercised (1.58 ± %/d) compared to control (1.09 ± %/d) muscles. In total, 90 proteins were included in the Dynamic Proteome Profiling. There were no significant between‐group differences in the muscle proteome prior to exercise training and no changes in protein abundance occurred in the muscle of participants in the non‐exercise group. In contrast, 24 proteins exhibited statistically significant differences in either synthesis rate or abundance in response to resistance training. The most common pattern of response was an increase in turnover. For example, the synthesis rate of myosin heavy chain IIa was 2‐fold greater in exercised muscle but this was not associated with a statistically significant increase in protein abundance. Conversely, 3 glycolytic enzymes (beta‐enolase, phosphoglycerate mutase 2 and triosephosphate isomerase) became significantly less abundant in exercise‐trained muscle despite exhibiting significantly elevated rates of synthesis. This suggests protein degradation was increased to a greater extent than the measured increase in synthesis. Our findings provide empirical evidence that the contributions that synthesis and degradation make to changes in protein abundance induced by resistance exercise differs on a protein by protein basis.

Support or Funding Information

This project was funded, in part by a CRN Grant 2013000443 to JAH