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ToolsCompareMGF (Mechano Growth Factor) vs P21

MGF (Mechano Growth Factor) vs P21

Side-by-side comparison of key properties, dosing, and research.

Anabolic & IGF
MGF (Mechano Growth Factor)
Cognitive EnhancementAnti-Aging & Longevity
P21
Summary
MGF (Mechano Growth Factor) is a splice variant of IGF-1 that is locally produced in muscle tissue in response to mechanical damage from exercise. It activates muscle satellite cells (stem cells) to proliferate and repair damaged fibers, making it specifically targeted at exercise-induced hypertrophy.
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.
Half-Life
Native MGF: minutes. PEG-MGF: ~3 days
Not well characterized; likely short, but neurogenic effects persist long after administration
Admin Route
SubQ, IM
SubQ, Intranasal
Research
Typical Dose
200–400 mcg
100–500 mcg
Frequency
1–2 times per week
Once daily
Key Benefits
  • Activates muscle satellite cells for repair and growth
  • Accelerates recovery from muscle damage
  • Synergistic with IGF-1 LR3 (different mechanisms)
  • Promotes muscle hypertrophy specifically at exercised muscles
  • Faster recovery between training sessions
  • Potential for injury repair in connective tissue
  • 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
Side Effects
  • Muscle soreness (satellite cell activation)
  • Injection site irritation
  • Hypoglycemia risk (modest, less than IGF-1 LR3)
  • Generally well tolerated in animal studies
  • Limited human clinical data
  • Injection site reactions
  • Potential mild fatigue at initiation
Stacks With