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P21 (P021)
Preclinical
Research chemical
Summary
Orally bioavailable CNTF-derived tetrapeptide (adamantylated) that enhances BDNF signaling, neurogenesis, and reduces tau/Aβ pathology in Alzheimer's mouse models.
Categories
Cognitive & Nootropic, Longevity
Mechanism
Competitively inhibits LIF signaling and increases BDNF transcription/expression; activates TrkB-linked PLC/PKC, MEK/ERK, and PI3K/Akt cascades; reduces tau hyperphosphorylation via GSK-3β pathway effects. Promotes hippocampal neurogenesis and synaptic plasticity.
Half-life
Designed for oral stability; exact human half-life unpublished
Routes
Oral; Subcutaneous injection
Legal / access
Investigational neurotrophic research peptide. Not FDA-approved for cognitive impairment.
Key risks
- Unknown human safety
- Theoretical CNTF-pathway effects
Common claims
- Neurogenesis boost
- Alzheimer prevention narratives
- Oral nootropic peptide
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