Studied effects

• muscle satellite cell activation following mechanical loading
• autocrine/paracrine local muscle repair signal (distinct from systemic IGF-1)
• progenitor cell proliferation and fusion enhancement in vitro
• PEG-MGF variant extends half-life for research applications — no human clinical data for either form

Mechanism

Splice variant of IGF-1; acts locally at site of muscle damage to activate satellite cells (muscle stem cells) for repair and hypertrophy