P21 vs PE-22-28
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.
- 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
- Not well characterized; likely short, but neurogenic effects persist long after administration
- Relatively short; CNS effects may persist due to neurogenic mechanisms
- Admin Route
- SubQ, Intranasal
- SubQ, Intranasal
- Research
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- Typical Dose
- 100–500 mcg
- 200–400 mcg
- 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
- 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
- Generally well tolerated in animal studies
- Limited human clinical data
- Injection site reactions
- Potential mild fatigue at initiation
- 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
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