DES IGF-1 acts primarily as an agonist of the IGF-1 receptor (IGF-1R). By lacking the first three amino acids, it binds weakly to IGFBPs, allowing greater availability to interact with the receptor. Binding to IGF-1R triggers receptor autophosphorylation and activation of key intracellular signaling pathways:
- PI3K/Akt pathway: promotes cell survival, protein synthesis, and inhibition of apoptosis.
- MAPK/ERK pathway: stimulates cell proliferation and differentiation.
- Glucose transport: increases glucose uptake in muscle and adipose cells, similar to insulin but with a weaker hypoglycemic effect.