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ToolsCompareP21 vs Cortagen

P21 vs Cortagen

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

Cognitive EnhancementAnti-Aging & Longevity
P21
Anti-Aging & LongevityRecovery & Repair
Cortagen
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.
Cortagen is a synthetic tetrapeptide (Ala-Glu-Asp-Pro) developed at the St. Petersburg Institute of Bioregulation as a cardioprotective and vascular bioregulator. It stimulates repair of cardiac and vascular tissue, with demonstrated benefits for coronary artery disease, atherosclerosis, and cardiac aging.
Half-Life
Not well characterized; likely short, but neurogenic effects persist long after administration
Short peptide half-life; gene regulatory effects persist beyond peptide clearance
Admin Route
SubQ, Intranasal
SubQ, IM, Oral
Research
Typical Dose
100–500 mcg
10 mg SC or IM daily
Frequency
Once daily
Once daily
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
  • Cardioprotective — protects cardiac tissue from ischemic damage
  • Promotes cardiac regeneration and repair
  • Improves vascular endothelium function
  • Reduces atherosclerosis progression
  • Anti-aging effect on heart muscle cells
  • Improves cardiac output and exercise capacity
  • Reduces oxidative stress in cardiovascular tissue
  • May reduce arrhythmia frequency
Side Effects
  • Generally well tolerated in animal studies
  • Limited human clinical data
  • Injection site reactions
  • Potential mild fatigue at initiation
  • Excellent safety profile
  • Mild injection site reactions
  • Rare: transient hypotension
  • Rare: mild arrhythmia at initiation in cardiac patients
Stacks With