P21 vs SS-31 (Elamipretide)
Side-by-side comparison of key properties, dosing, and research.
Cognitive EnhancementAnti-Aging & Longevity
P21Anti-Aging & Longevity
SS-31 (Elamipretide)- 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.
- SS-31 (Elamipretide) is a synthetic mitochondria-targeting tetrapeptide that concentrates in the inner mitochondrial membrane and protects cardiolipin from oxidative damage. It is one of the most promising mitochondrial longevity compounds, studied in clinical trials for heart failure, renal disease, and age-associated mitochondrial dysfunction.
- Half-Life
- Not well characterized; likely short, but neurogenic effects persist long after administration
- ~2–5 hours
- Admin Route
- SubQ, Intranasal
- SubQ
- Research
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- Typical Dose
- 100–500 mcg
- 5–10 mg
- Frequency
- Once daily
- Daily to several times 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
- Restores mitochondrial function and ATP production
- Protects inner mitochondrial membrane cardiolipin
- Reduces mitochondrial reactive oxygen species (ROS)
- Improves exercise capacity and reduces fatigue
- Cardioprotective — studied in heart failure trials
- Renoprotective — reduces ischemic kidney injury
- Anti-aging via mitochondrial preservation
- Potential in neurodegenerative disease prevention
- Side Effects
- Generally well tolerated in animal studies
- Limited human clinical data
- Injection site reactions
- Potential mild fatigue at initiation
- Injection site irritation
- Nausea (rare)
- Generally well-tolerated in clinical trials
- Stacks With
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