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PE-22-28

Also known as: PE-22-28 Peptide, Spadin analog, Neurogenic Antidepressant Peptide

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

Relatively short; CNS effects may persist due to neurogenic mechanisms

Route

SubQ, Intranasal

Category

Cognitive Enhancement

Studies

1 reference

Key Benefits

  • 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

Mechanism of Action

TREK-1 (TWIK-related K⁺ channel 1) is a two-pore domain potassium channel expressed in serotonergic raphe neurons. TREK-1 hyperpolarizes these neurons, suppressing serotonin release. PE-22-28, like its parent compound spadin, blocks TREK-1 channels to depolarize serotonergic neurons and increase serotonin release. Additionally, PE-22-28 activates BDNF-TrkB signaling in the hippocampus, promoting adult neurogenesis (new neuron formation) — a mechanism thought to underlie the sustained antidepressant effect distinct from fast serotonergic effects.

Dosing Protocols

Antidepressant / Neurogenic Protocol

Dose
200–400 mcg
Frequency
Once daily
Timing
Morning SC injection or intranasal
Cycle
4–12 weeks

Neurogenic effects may require 2–4 weeks to manifest fully; fast serotonergic effects may be felt sooner

Cognitive Enhancement

Dose
100–200 mcg
Frequency
Daily or 5x per week
Timing
Morning
Cycle
4–8 weeks

Cycle: 8 weeks on, 4 weeks off

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Side Effects

  • Generally well tolerated in animal models
  • Limited human data available
  • Possible mild headache or transient mood changes at initiation
  • Injection site reactions (SC)

Contraindications

Limited clinical human safety data. Use with caution alongside other serotonergic medications. Not for use in bipolar disorder without psychiatric supervision.

Storage

Lyophilized: -20°C. Reconstituted: 4°C, use within 30 days. Protect from light.

  1. 1.
    Shortened Spadin Analogs Display Better TREK-1 Inhibition, In Vivo Stability and Antidepressant Activity

    Djillani A, Pietri M, Moreno S, Heurteaux C, Mazella J, Borsotto M · Frontiers in pharmacology · 2017PubMed Verified

Medical disclaimer: This information is for educational purposes only and does not constitute medical advice. Many compounds listed are research chemicals not approved for human use. Always consult a qualified healthcare professional before starting any protocol.

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