GSE195585
Supplementation of specific collagen peptides following high-load resistance exercise upregulates gene expression in pathways involved in skeletal muscle signal transduction
Previous evidence suggests that resistance training in combination with specific collagen peptides (CP) improves adaptive responses of the muscular apparatus. Although beneficial effects have been repeatedly demonstrated, the underlying mechanisms are not well understood. Therefore, the primary objective of the present randomized trial was to elucidate differences in gene expression pathways related to myofibrillar protein synthesis following acute high-load resistance exercise with and without CP intake.  Recreationally active male participants (n=30) were equally randomized to high-load (80% one-repetition maximum) leg extension exercise in combination with 15g CP or placebo (PLA) supplementation. Muscle biopsies from the vastus lateralis muscle were obtained at baseline as well as 1h, 4h and 24h post exercise to investigate gene expression using next generation sequencing analysis.   Several important anabolic pathways including PI3K-Akt and MAPK pathways were significantly upregulated at 1h and 4h post-exercise (p<0.05). Significant between-group differences for both pathways were identified at the 4h time point. Gene expression related to the mTOR pathway demonstrated a higher visual increase in the CP group compared to PLA with no statistically significant group differences.  The current findings revealed a significantly higher upregulation of key anabolic pathways (PI3K-Akt, MAPK) in human skeletal muscle in response to acute resistance training combined with intake of 15 g collagen peptides compared to placebo. Further investigations are needed to examine potential long-term effects on anabolic pathways on the protein level. Overall design: A randomized, controlled, double-blinded design was implemented to investigate the effects of collagen peptides (CP) ingestion combined with acute resistance exercise on skeletal muscle anabolic gene expression.   One week before the acute exercise trial, participants visited the laboratory and underwent a preliminary screening, which included a survey of the complete medical history and a general medical examination to ensure compliance with the study-specific inclusion criteria. After the assessment of eligibility, participants were randomly allocated into two groups either supplemented with CP or placebo. A random number generator was used for allocation sequence generation. All outcome assessors, statistical analysis group, as well as trainers and participants were blinded to group assignments.