PEG-MGF: PEGylated Mechano Growth Factor (IGF-1Ec)
PEGylated splice variant of IGF-1 (IGF-1Ec) released by mechanically loaded muscle. Pre-clinical regenerative evidence; no approved human use.
🐀 Animal
- Full name
- PEG-MGF (PEGylated IGF-1Ec / mechano growth factor)
- Class
- IGF-1 splice variant — PEGylated
- Half-life
- Extended vs native MGF (hours vs minutes)
- Route
- Research: subcutaneous or intramuscular
- Developer
- Academic / research-chemical suppliers
- Regulatory status
- No approval; WADA-banned
What it is
MGF is a C-terminal splice variant of IGF-1 (IGF-1Ec) produced locally by skeletal muscle in response to mechanical loading and damage. PEGylation extends the otherwise very short half-life. It is hypothesised to activate satellite cells and drive muscle regeneration.
How it works
Mechanical loading splits IGF-1 transcripts to favour the Ec exon. The E-peptide released from MGF acts on satellite-cell receptors (distinct from the IGF-1 receptor) to trigger proliferation and fusion with existing fibres.
Native MGF has a half-life measured in minutes; PEGylation stabilises the peptide for sustained exposure, allowing research without repeated daily injections. No validated therapeutic role exists.
What the research shows
Regenerative and cardiac studies in rodents form the evidence base; human data are anecdotal.
Goldspink G. (2005) — MGF muscle satellite cell activation
Goldspink G. et al., J Musculoskelet Neuronal Interact 2005;5:232–236. 🐀 Animal
In rats, direct injection of MGF peptide into damaged muscle accelerated regeneration and increased satellite-cell activity.
Effects were distinct from IGF-1 and PEG-MGF improved practical dosing.
Limitations: Rodent only; no placebo-controlled human trials.
Carpenter V. et al. (2008) — cardiac ischaemia model
Carpenter V. et al., Acta Physiol (Oxf) 2008;193:335–345. 🐀 Animal
PEG-MGF reduced infarct size and improved cardiac function in rodent ischaemia-reperfusion models.
Results supported the concept that E-peptide action is distinct from IGF-1 receptor signalling.
Limitations: Preclinical; no translation to humans.
Safety and limitations
No controlled human safety data. Research-chemical products vary widely in purity and sequence. IGF-1-related concerns (hypoglycaemia, theoretical tumour growth) may apply but are not characterised.
WADA-banned. Clinical use is not supported by evidence.