Supplementation of Specific Collagen Peptides Following High-Load Resistance Exercise Upregulates Gene Expression in Pathways Involved in Skeletal Muscle Signal Transduction

Abstract

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 skeletal muscle signal transduction following acute high-load resistance exercise with and without CP intake. Recreationally active male participants were equally randomized to high-load leg extension exercise in combination with 15 g CP or placebo (PLA) supplementation. Muscle biopsies from the vastus lateralis muscle were obtained at baseline as well as 1, 4 and 24 h 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 1 and 4 h post-exercise. Significant between-group differences for both pathways were identified at the 4 h time point demonstrating a more pronounced effect after CP intake. Gene expression related to the mTOR pathway demonstrated a higher visual increase in the CP group compared to PLA by trend, but failed to achieve statistically significant group differences. The current findings revealed a significantly higher upregulation of key anabolic pathways (PI3K-Akt, MAPK) in human skeletal muscle 4 h following an acute resistance training combined with intake of 15 g of specific collagen peptides compared to placebo. Further investigations should examine potential relationships between upregulated gene expression and changes in myofibrillar protein synthesis as well as potential long-term effects on anabolic pathways on the protein level.

The effect of specific bioactive collagen peptides on function and muscle remodeling during human resistance training

“…24 Collagen has been found to enhance synthesis or growth in a range of musculoskeletal tissues, such as cartilage, 25 ligament, 26 and bone. 27,28 Specific to musculotendinous tissues, collagen peptides have been shown to induce myoblast differentiation and myotube hypertrophy in mouse skeletal muscle cells in-vitro by activating the mTOR signaling pathway, 29 upregulate human gene expression related to signal transduction pathways activated in muscular remodeling 30 and there is emerging evidence that collagen supplementation in humans can enhance the rehabilitation of injured tendons. [31][32][33] These benefits may be due to the ability of bioactive collagen peptides to upregulate the synthesis of ECM proteins in various tissues via a stimulatory cell effect, while also providing the specific amino acid building blocks for body collagens.…”

Collagen peptide supplementation for pain and function: is it effective?

“…Although the body of literature on the benefits of supplementing with collagen peptides is expanding, information on the mechanism of action of collagen peptide supplementation is lacking. An emerging hypothesis is that specific dipeptides and tripeptides, especially those containing hydroxyproline (bioactive peptides), upregulate gene expression for the synthesis of type I collagen [28,29]. Collagen, especially type I fibers (in tendons and ligaments), is made of triple helical structures composed of Gly-X-Y (glycine-X-Y), with glycine (Gly) constituting 1/3 of the helix, and proline (Pro) and 4-hydroxyproline (Hyp) frequently occupying the X and Y positions, respectively (Gly-Pro-Hyp) [5].…”

Reduction in systemic muscle stress markers after exercise-induced muscle damage following concurrent training and supplementation with specific collagen peptides – a randomized controlled trial

“…This suggests greater changes in collagen-specific proteins after 12 weeks of CP supplementation combined with resistance training (RT) ( 14 ). A recent study investigating gene expression patterns following strenuous bouts of knee extensions prior to a single dose of CP showed significant upregulation of the PI3K/Akt and MAPK pathways, both known to be essential for (myofibrillar) protein synthesis ( 15 ). The PI3K/Akt pathway may also play a role in connective tissue protein synthesis by mediating TGF-β2 signaling and inducing mRNA expression of COL1A1 & COL1A2 (collagen type 1 genes) in human pigment cells ( 16 ).…”