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ToolsComparePE-22-28 vs SLU-PP-332

PE-22-28 vs SLU-PP-332

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

Cognitive Enhancement
PE-22-28
Recovery & RepairFat Loss & Metabolic
SLU-PP-332
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.
SLU-PP-332 is a small molecule exercise mimetic that activates estrogen-related receptors ERRalpha and ERRdelta (ERRa/d), transcription factors that drive oxidative metabolism programs. In animal studies it significantly enhanced endurance capacity and metabolic fitness without exercise, mimicking many of the cardiovascular and metabolic adaptations of aerobic training.
Half-Life
Relatively short; CNS effects may persist due to neurogenic mechanisms
Not established in humans; rodent pharmacokinetics suggest hours
Admin Route
SubQ, Intranasal
Oral (research), Subcutaneous (research)
Research
Typical Dose
200–400 mcg
Not established for humans; rodent studies used ~100 mg/kg/day
Frequency
Once daily
Once daily in rodent studies
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
  • Significant enhancement of aerobic endurance capacity
  • Increases mitochondrial density and oxidative metabolism in muscle
  • Promotes beneficial shift toward oxidative muscle fiber phenotype
  • Improves cardiac efficiency and cardiovascular fitness markers
  • Potential for obesity, metabolic syndrome, and heart failure treatment
  • Exercise mimetic for populations unable to exercise (disability, frailty, disease)
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)
  • Limited human data; all studies are preclinical (rodent)
  • Unknown cardiovascular effects with long-term or high-dose use in humans
  • Potential hormonal interactions via ERR pathway (ERRs modulate estrogen-related signaling)
  • Off-target effects not fully characterized
Stacks With