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ToolsCompareSS-31 (Elamipretide) vs PE-22-28

SS-31 (Elamipretide) vs PE-22-28

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

Anti-Aging & Longevity
SS-31 (Elamipretide)
Cognitive Enhancement
PE-22-28
Summary
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.
PE-22-28 is a synthetic analog of spadin derived from sortilin, designed to block TREK-1 potassium channels with rapid-onset antidepressant and neurogenic effects. It shows fast-acting depression relief (within 24 hours) and promotes hippocampal neurogenesis.
Half-Life
~2–5 hours
Relatively short; CNS effects may persist due to neurogenic mechanisms
Admin Route
SubQ
SubQ, Intranasal
Research
Typical Dose
5–10 mg
200–400 mcg
Frequency
Daily to several times per week
Once daily
Key Benefits
  • 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
  • Rapid-onset antidepressant effects (within 24 hours)
  • Promotes hippocampal neurogenesis
  • Improves cognitive performance and memory
  • Reduces anxiety and depressive behavior
  • Novel mechanism — does not act on serotonin/dopamine/GABA receptors directly
  • May help treatment-resistant depression
  • Neuroprotective effects
Side Effects
  • Injection site irritation
  • Nausea (rare)
  • Generally well-tolerated in clinical trials
  • Generally well tolerated in animal models
  • Limited human data available
  • Possible mild headache or transient mood changes at initiation
  • Injection site reactions (SC)
Stacks With