Supplement Scholar
Neurotrophic

P21

Research compound. This is not a dietary supplement. Unless it is identified as an approved prescription drug, it is not approved by the FDA for human use. This page summarizes published research for education only; we do not sell it or link to sellers.

P21. CNTF-derived peptide reported to promote neurogenesis in preclinical work.

How it works. Mimics CNTF-mediated neurogenic signaling, increasing hippocampal neurogenesis and BDNF expression in animal models.

What the research supports. 2 graded claims. Strongest: Targets adult neurogenesis directly (preclinical).

Hormonal impact. Effects on BDNF, CNTF pathway.

Side effects and interactions. 0 medication interactions listed. Serious: Long-term safety unknown.

Stacking. Pairs well with Aerobic exercise. Avoid combining with Active glial tumors.

Common forms. Available as Subcutaneous injection (research).

Community. Experiences from people who have tried P21. Anecdotes are not medical advice.

P21. CNTF-derived peptide reported to promote neurogenesis in preclinical work.

No single structure

What it is

P21 is a 21-amino-acid peptide derived from ciliary neurotrophic factor (CNTF) that retains neurogenic activity without CNTF's systemic side effects.

Also called

Cdk5 activator-derived peptide

How it works

Mimics CNTF-mediated neurogenic signaling, increasing hippocampal neurogenesis and BDNF expression in animal models.

Pathways

  • CNTF receptor signaling
  • BDNF induction
  • Adult hippocampal neurogenesis

Effects

  • +Adult hippocampal neurogenesis in models supports
  • +Memory in animal AD models supports

What the research supports

Targets adult neurogenesis directlypreclinical
Avoids CNTF systemic side effects in animalspreclinical

Strong: consistent results across large trials or meta-analyses. Moderate: several trials, mostly positive. Limited: small or mixed studies. Preclinical: animal or cell research only.

Hormonal impact

↑BDNFincreases
~CNTF pathwaymodulates

Side effects & interactions

Common side effects

  • No characterized human profile

Serious

  • Long-term safety unknown

No notable medication interactions listed.

Check any supplement–medication combination with your pharmacist before starting.

Combines with

Pairs well

  • Aerobic exerciseIndependently increases BDNF and adult neurogenesis.

Avoid combining

  • Active glial tumorsCNTF-pathway activation in gliomas is under-characterized.

Common forms

  • Subcutaneous injection (research)

Discussion

Loading discussion…