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ToolsComparePE-22-28 vs Pal-AHK

PE-22-28 vs Pal-AHK

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

Cognitive Enhancement
PE-22-28
Skin & CosmeticAnti-Aging & Longevity
Pal-AHK
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.
Pal-AHK is the palmitoylated form of the AHK-Cu copper tripeptide, created by attaching a palmitic acid chain to enhance skin penetration and lipid bilayer affinity. The palmitoyl modification significantly improves dermal bioavailability compared to unmodified AHK, making it particularly effective in anti-aging and hair growth formulations.
Half-Life
Relatively short; CNS effects may persist due to neurogenic mechanisms
Extended (lipid depot effect in stratum corneum)
Admin Route
SubQ, Intranasal
Topical
Research
Typical Dose
200–400 mcg
0.01–0.05% in formulation
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
  • Enhanced skin penetration vs. unmodified AHK-Cu
  • Stimulates dermal collagen and elastin production
  • Promotes hair follicle anagen phase
  • Antioxidant and wound healing activity
  • Firming and plumping effect on aging skin
  • Improved bioavailability via lipid bilayer incorporation
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 well-tolerated
  • Mild irritation at high concentrations in sensitive skin
  • Possible comedogenicity at very high palmitate concentrations (formulation-dependent)
Stacks With