Reliability of Protein Abundance and Synthesis Measurements in Human Skeletal Muscle.
Level 4 - case-series / case-control
Small methodological and technical reliability study in human tissue samples
PubMed 31622029 · doi:10.1002/pmic.201900194
What was done
The technical repeatability of dynamic proteome profiling (DPP) was evaluated for measuring relative protein abundance (ABD) and fractional synthesis rates (FSR) in human skeletal muscle. Muscle biopsies were collected from 4 male participants who ingested deuterium oxide (4 × 50 mL/day) for 14 days. Samples were analyzed using LC-MS, with label-free quantitation for ABD and peptide mass isotopomer changes for FSR calculations.
What was found
Out of 101 proteins analyzed for ABD, 54 met stringent criteria for FSR determination. The median protein FSR was 1.63%/day (Q1: 1.07%, Q3: 3.24%). The technical coefficient of variation (CV) for ABD had a median of 3.6% (Q1: 1.7%, Q3: 6.7%), while the median CV for FSR was 10.1% (Q1: 3.5%, Q3: 16.5%).
Why it matters
Dynamic proteome profiling can reliably quantify individual protein turnover rates in human skeletal muscle with technical variation well below common proteomics acceptability thresholds.
Limits
The study evaluated a very small cohort (n = 4) consisting entirely of male participants. Biological variability across diverse populations or physiological states was not assessed, and only a subset of detected proteins met quality criteria for synthesis rate quantification.
Cited by
- supports Skeletal muscle protein turns over at a rate of 1% to 2% per day, renewing completely in approximately 50 to 100 days.