IGF-1 Ec (Mechano Growth Factor)
The IGF-1 Ec splice variant, whose E-domain-derived peptide is marketed as Mechano Growth Factor. It is proposed to activate satellite cells after muscle damage. Human evidence is minimal; use is largely preclinical and anecdotal.
01 Overview
IGF-1 Ec is a splice variant of the IGF-1 gene produced locally in mechanically loaded muscle. The 24-amino-acid C-terminal E-peptide (the 'MGF' peptide) is thought to act on muscle satellite cells to promote proliferation and repair, distinct from the systemic mature IGF-1 domain.
Most supporting data come from rodent and cell-culture studies; robust human trials are lacking. In the research-peptide market it is sold as MGF or PEG-MGF, but the specific full IGF-1 Ec variant peptide described here remains poorly characterised in humans and its outcomes are largely anecdotal.
02 Mechanism
The IGF-1 Ec E-domain peptide is proposed to stimulate satellite-cell proliferation and delay differentiation after muscle damage, acting partly independently of the classic IGF-1 receptor.
03 Dosing
| Tier | Dose | Route | Notes |
|---|---|---|---|
| Anecdotal (research) | 100–200 mcg | SubQ | Self-reported local/post-workout dosing; no validated human protocol. |
04 Effects
| Effect | Magnitude | Evidence | |
|---|---|---|---|
| Satellite-cell activationPromotes muscle satellite-cell proliferation in preclinical models. | in vitro/rodent | Preclinical | |
| Muscle repair (claimed)Anecdotally used to aid recovery from muscle damage; no human trial confirmation. | unquantified in humans | Anecdotal |
05 Side effects
| Effect | Severity | Frequency | Evidence | Countermeasures |
|---|---|---|---|---|
| Injection-site reactionsLocal redness or swelling. | Mild | Common | Anecdotal | |
| Unknown long-term safetyIGF pathway activation carries theoretical proliferative risk; no human safety data. | Moderate | Unknown | Unconfirmed |