P21 (Peptide)
Overview
A small synthetic peptide derived from the active region of ciliary neurotrophic factor (CNTF) designed to promote neurogenesis and synaptic plasticity. P21 is a tetrapeptide that crosses the blood-brain barrier and enhances dentate gyrus neurogenesis by increasing BDNF expression.
Mechanism of Action
Unlike full-length CNTF, P21 does not activate the JAK-STAT pathway or produce the anorectic and immunogenic effects of the parent protein.
Research Summary & Key Findings
Preclinical studies in Alzheimer's disease mouse models showed significant improvements in spatial learning and memory, correlated with increased hippocampal neurogenesis and synaptic density (Bolognin et al., Neurobiol Dis, 2014). Reduced tau hyperphosphorylation and neurofibrillary pathology in transgenic mice. Currently in preclinical development with no human clinical trials completed.
Clinical Status
P21 (Peptide) is in the research phase with limited clinical data in humans. Current evidence is primarily derived from preclinical (animal or in vitro) studies.
Administration Routes
References
Primary literature
- PubMed — "P21"
Peer-reviewed literature indexed by the National Library of Medicine.
- ClinicalTrials.gov — "P21"
Registered interventional and observational studies, including status and phase.
- PubChem — "P21"
Chemical structure, molecular properties, and bioactivity data.
Study-level citations for this compound are being verified against the primary sources before publication. The database queries above return the current indexed literature in the meantime.
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