NO. 037 · STAGE 1 · Lv. 72 · HP 135
PEG-MGF
PEGylated Mechano Growth Factor · IGF-1Ec
ALIASES
PEG-MGF, PEGylated MGF, mechano growth factor, IGF-1Ec, IGF-1Ec splice variant
CLASS
Synthetic peptide · PEGylated IGF-1 Ec splice variant
FORMULA
C121H200N42O39 (24-residue core, plus PEG conjugate)
SEQUENCE
C-terminal Ec exon: YQPPSTNKNTKSQRRKGSTFEERK (24 residues, PEGylated)
HALF-LIFE
Several days (PEGylated vs. <30 minutes for native MGF)
ROUTES
Subcutaneous (research) · Intramuscular (research)
MECHANISM OF ACTION
PEGylated form of mechano growth factor (MGF), the IGF-1Ec splice variant produced locally in muscle in response to mechanical loading or injury. Drives satellite cell activation, proliferation, and local hypertrophy. PEG conjugation extends the otherwise sub-hour half-life to support practical research dosing.
EVIDENCE GRADES
Goldspink and Hill multi-paper evidence base for MGF-induced satellite cell activation and local hypertrophy after mechanical loading.
Intramuscular MGF injections produce local hypertrophy in rodent and rabbit models.
No completed long-term human Phase 3 trials.
MECHANISM CATEGORIES
RESEARCH CONDITIONS
SAFETY
Side effects
- Injection-site reactions
- Local swelling/redness with IM administration
- Limited published Western safety data
- Theoretical hypoglycemia (IGF-1R activation)
Known interactions
- Insulin / glucose-lowering agents (theoretical hypoglycemia risk via IGF-1R)
- Concurrent rhGH not recommended
Contraindications
- Active malignancy
- Pregnancy/lactation
- Diabetic retinopathy
REGULATORY STATUS
FDA · Not FDA-approved. Research-use only.
WADA · Prohibited at all times under WADA Section S2 (Growth Factors sub-category).
STORAGE
Lyophilized · -20 °C 24 months
Reconstituted · 2-8 °C, 14-28 days
PEER-REVIEWED EVIDENCE
- Goldspink G, Yang SY. Mechano growth factor and a method for improvement of muscle. J Musculoskelet Neuronal Interact 2002. link →
- Hill M, Wernig A, Goldspink G. Muscle satellite (stem) cell activation during local tissue injury and repair. J Anat 2003. link →
FAQ · 8 QUESTIONS
▶ What is PEG-MGF?
PEG-MGF is a PEGylated form of mechano growth factor (MGF), the IGF-1Ec splice variant produced locally in muscle in response to mechanical loading or injury. PEGylation extends the otherwise sub-30-minute half-life to support practical research dosing.
▶ What is MGF?
Mechano Growth Factor (MGF) is a splice variant of IGF-1 with an alternative C-terminal Ec exon (vs the canonical Ea exon). It is produced locally in skeletal muscle in response to mechanical loading or injury and drives satellite-cell activation, proliferation, and local hypertrophy. The Ec peptide acts independently of the IGF-1Ea mature peptide.
▶ PEG-MGF vs IGF-1 LR3 · which is better?
Different mechanisms. IGF-1 LR3 is a systemic IGF-1R agonist that drives whole-body anabolism. PEG-MGF acts more locally on satellite-cell activation at the site of injection or injury and does not produce the same systemic IGF-1R signaling. Research protocols select between them based on the local-vs-systemic research design.
▶ Is PEG-MGF FDA-approved?
No. Research-use only.
▶ Is PEG-MGF WADA-prohibited?
Yes. PEG-MGF is prohibited at all times under WADA Section S2 in the Growth Factors sub-category.
▶ What is the half-life of PEG-MGF?
Several days, depending on the PEG conjugate. Native MGF has a half-life under 30 minutes; the PEGylation strategy extends systemic exposure to support practical dosing in animal-model research.
▶ How is PEG-MGF dosed in research?
Animal-model and community-reported research protocols use 200-1000 mcg per administration, subcutaneous or intramuscular at the target muscle, post-workout in resistance-training research. No human dose is recommended by this wiki.
▶ Why is PEG-MGF injected locally?
MGF is the local IGF-1 variant produced in response to muscle loading. Local intramuscular injection at the target muscle group is the standard research approach to maximize satellite-cell activation at that specific site rather than driving systemic IGF-1R signaling.
SIGNATURE MOVES
Activates muscle satellite cells. Local hypertrophy signal.
Extended half-life vs native MGF. Stable systemic exposure.
SOURCED FROM PEPPU LABS
Reference compounds documented on this page are available as research-grade material at Peppu Studio · ≥99% purity · per-batch Certificate of Analysis. For laboratory research use only. No human dose is recommended by this wiki.
▶ LAST UPDATED · 2026-05-25