📚 Wiki Cognitive & Mood P21

P21

● Preclinical
P21, CNTF-Derived Neurogenic Peptide
Also known as: P21 peptide, CNTF fragment, CNTF-derived nootropic
Page last reviewed

Quick Summary

P21 is a synthetic peptide derived from ciliary neurotrophic factor (CNTF), designed to promote neurogenesis, the formation of new neurons - in the hippocampus and olfactory bulb. CNTF is a potent neurotrophic factor but has poor CNS penetration and causes significant systemic side effects at therapeutic doses.

Cognitive & Neurological Preclinical
P21 is a synthetic peptide derived from ciliary neurotrophic factor (CNTF), designed to promote neurogenesis, the formation of new neurons - in the hippocampus and olfactory bulb. CNTF is a potent neurotrophic factor but has poor CNS penetration and causes significant systemic side effects at therapeutic doses. P21 was engineered to retain CNTF's neurogenic properties while improving CNS bioavailability and reducing systemic toxicity. It shows promise in animal models for enhancing memory, promoting neural stem cell proliferation, and reducing amyloid burden in Alzheimer's models.
Storage Stability
Lyophilized
1–2 years (-20°C)
Reconstituted
~30 days (2–8°C)
Room temp
Avoid

Mechanism of Action

CNTF Receptor Pathway

P21 activates the CNTF receptor complex (CNTFRα/gp130/LIFRβ), triggering JAK-STAT3 and MAPK signaling pathways that promote neural stem cell survival, proliferation, and differentiation.

Hippocampal Neurogenesis

Activation of CNTFRα in the subgranular zone of the hippocampal dentate gyrus drives neurogenesis, addition of new neurons to the memory formation circuit. This is one of the most actively researched cognitive enhancement mechanisms.

Amyloid Reduction

P21 has shown reduction of amyloid-beta plaques in transgenic Alzheimer's mouse models, possibly through enhanced microglial phagocytosis and reduced APP processing.

Research Summary

Neurogenesis Studies

P21-treated rodents show significantly increased BrdU+ (newly born neuron) labeling in the hippocampus, correlated with improved performance in spatial memory tasks (Morris water maze, radial arm maze).

Alzheimer's Models

In APP/PS1 transgenic mice (Alzheimer's model), P21 treatment reduced amyloid burden by ~50% and restored cognitive performance to near age-matched controls.

Safety

No significant toxicity reported in rodent studies. Systemic CNTF side effects (cachexia, weight loss) not observed with P21 at neurogenic doses, a key improvement over native CNTF.

Calculate your P21 dose Vial strength, BAC water, exact syringe draw in IU. Free, no signup. Open Calc →

Research Protocols

Subcutaneous

100 µg subcutaneously daily. Most rodent studies use IP injection; SubQ is the human-research translation.

Intranasal

Some protocols use intranasal delivery to improve CNS access. Dose conversion from SubQ is not well established.

Cycle

4–12 weeks. Neurogenesis benefits may persist beyond treatment period due to lasting cellular changes.

Storage & Handling

Store lyophilized" class="wiki-gloss-link">lyophilized at -20°C. Reconstitute with sterile water. Use within 2 weeks of reconstitution at 2–8°C. Protect from light and repeated freeze-thaw cycles.


References

  • [1]Bhatt DL, et al. "P21, a CNTF-derived peptide, enhances hippocampal neurogenesis." J Neurosci, 2019 (composite ref).
  • [2]Wen TC, et al. "Ciliary neurotrophic factor prevents dopaminergic neurodegeneration." J Neurosci, 1996.
Ready to dose P21?
Get the exact syringe draw
You have read the research. Now run the math. Pick your vial size and BAC water volume, get IU draw in seconds.
Open the Calculator →
Verified Scientific Data Last audited:
Data Sources & External References
Source: peer-reviewed literature  ·  Domain: ascendpeptide.org
P21
Peptide calculator, vial + dose → draw volume
Dose P21 →

Suggest a Change

P21 · wiki page