MGF is a splice variant of the IGF-1 gene (IGF-1Ec) produced locally by muscle tissue in response to mechanical loading or damage.
Mechanism — Acts as a tissue-specific signal that activates satellite cells, the muscle stem cells responsible for repair and hypertrophy. Distinct C-terminal sequence drives the regenerative signal independent of systemic IGF-1 receptor binding.
Use case — Investigational for muscle injury recovery and hypertrophy support. Often used as PEG-MGF for extended half-life. Typical research dosing 200 mcg subcutaneous post-workout, locally near worked muscles.
Caveats — Sourcing variable. Localized injection logistics are awkward. Combine sensibly with BPC-157 and TB-500 in serious tissue-repair protocols.