PEG-MGF
PEG-MGF is a PEGylated synthetic analog of mechano growth factor (MGF), an IGF-1 splice variant produced locally in response to mechanical loading, engineered with polyethylene glycol attachment to extend its in vivo half-life from minutes to days. It is studied for skeletal muscle repair, hypertrophy, and satellite cell activation. Placed on FDA Category 2 list (September 29, 2023) as 'Mechano growth factor pegylated (PEG-MGF).'
Written by WhatPeptide Editorial Team · Last updated 2026-03-17
Half-life
Approximately 24-72 hours (PEGylation-extended)
Dosage range
200-400 mcg subcutaneously 1-2x weekly (research context)
Administration
Subcutaneous injection
Research level
Preliminary
How PEG-MGF works
Mechano growth factor activates distinct intracellular pathways from systemic IGF-1, particularly stimulating muscle satellite cell proliferation through an Akt-independent mechanism that may involve the unique E-domain of the MGF splice variant. PEGylation prevents rapid enzymatic degradation, enabling sustained engagement with receptors in damaged muscle tissue following systemic or local injection. Rodent studies demonstrate enhanced muscle fiber cross-sectional area and accelerated recovery after eccentric exercise or injury.
Also known as: PEGylated Mechano Growth Factor, PEG-Mechano Growth Factor, Pegylated IGF-1Ec
Research relevance
Side effects & safety
Contraindications
Consult a healthcare provider before use if any of these apply to you.
Key studies
-
Yang SY & Goldspink G — MGF and mature IGF-I in myoblast proliferation/differentiation
MGF E domain increases myoblast proliferation while inhibiting terminal differentiation; distinct from IGF-I receptor
PubMed 2002 -
Matheny RW Jr et al. — Mechano-growth factor minireview
MGF upregulated first after injury for satellite cell proliferation, followed by IGF-IEa for differentiation
PubMed 2010 -
Kandalla PK et al. — MGF-E peptide activates human muscle progenitor cells
MGF-24aa-E peptide increases proliferative lifespan and delays senescence of satellite cells
PubMed 2011
FAQ
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