P21 vs PEG-MGF
Side-by-side comparison of key properties, dosing, and research.
- Summary
- P21 is a synthetic peptide derived from CNTF (ciliary neurotrophic factor) that promotes hippocampal neurogenesis, enhances memory and spatial learning, and may reduce amyloid-beta pathology. It is used as a neurogenic and cognitive enhancer with potential anti-Alzheimer's applications.
- PEG-MGF (Pegylated Mechano Growth Factor) is a modified form of MGF (Mechano Growth Factor) where polyethylene glycol (PEG) chains have been attached to extend its half-life from minutes to days. Native MGF is released locally in muscle in response to mechanical stress and quickly degrades. PEGylation allows systemic administration with sustained circulation, enabling whole-body muscle repair and anabolic signaling rather than the purely local effect of native MGF.
- Half-Life
- Not well characterized; likely short, but neurogenic effects persist long after administration
- ~3 days (due to PEGylation)
- Admin Route
- SubQ, Intranasal
- SubQ
- Research
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- Typical Dose
- 100–500 mcg
- 200–400 mcg
- Frequency
- Once daily
- 2–3x per week
- Key Benefits
- Promotes hippocampal neurogenesis
- Enhances spatial memory and learning
- Increases BDNF expression
- Reduces amyloid-beta plaque formation (animal models)
- Anti-tau pathology potential
- Cognitive enhancement without stimulant effects
- Potential therapeutic for Alzheimer's and cognitive aging
- Extended half-life (~3 days) vs native MGF (minutes)
- Systemic muscle satellite cell activation via subcutaneous injection
- Promotes muscle fiber repair and hypertrophy throughout the body
- Enhanced recovery from intense training or muscle injury
- Synergistic with IGF-1 LR3 and growth hormone peptides
- Useful in sarcopenia, post-injury recovery, and athletic performance
- Single injection provides multi-day anabolic signaling
- Side Effects
- Generally well tolerated in animal studies
- Limited human clinical data
- Injection site reactions
- Potential mild fatigue at initiation
- Water retention and localized swelling
- Potential hypoglycemia at high doses
- Theoretical cancer growth risk (growth factor)
- Injection site reactions
- +1 more
- Stacks With
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