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ToolsComparePE-22-28 vs PGPIPN

PE-22-28 vs PGPIPN

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

Cognitive Enhancement
PE-22-28
Immune Support
PGPIPN
Summary
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.
PGPIPN is a bioactive hexapeptide (Pro-Gly-Pro-Ile-Pro-Asn) derived from beta-casein during enzymatic digestion. It exhibits anti-inflammatory properties via opioid receptor modulation and cytokine suppression, making it relevant for gut health, systemic inflammation, and as a component of casein-derived functional foods.
Half-Life
Relatively short; CNS effects may persist due to neurogenic mechanisms
Estimated 30-120 minutes (peptide degradation)
Admin Route
SubQ, Intranasal
Oral, Subcutaneous (research)
Research
Typical Dose
200–400 mcg
200-500 mg per day
Frequency
Once daily
Once or twice daily
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
  • Anti-inflammatory effects via cytokine suppression
  • Gut mucosal protection and intestinal barrier support
  • Opioid receptor modulation for gut motility regulation
  • Potential analgesic activity via central and peripheral opioid pathways
  • Explored for inflammatory bowel conditions and gut dysbiosis
  • Natural origin (food-derived) with favorable safety profile
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)
  • Generally very well-tolerated given food-derived origin
  • Theoretical opioid-mediated constipation at high doses
  • Rare milk protein allergy in casein-sensitive individuals
Stacks With