P21 (Cerebrolysin-derived)

A small synthetic peptide derived from the active region of ciliary neurotrophic factor (CNTF), identified through research aimed at creating a drug-like compound that replicates key neurotrophic effects of Cerebrolysin. P21 crosses the blood-brain barrier and promotes neurogenesis and synaptic plasticity without the mitogenic activity associated with full-length neurotrophic factors.

• Mimics the neurotrophic activity of CNTF by engaging the CNTF receptor alpha/gp130/LIF receptor complex
• Inhibits glycogen synthase kinase-3 beta (GSK-3beta), reducing tau hyperphosphorylation
• Stimulates dentate gyrus neurogenesis by promoting neural progenitor cell proliferation and differentiation
• Lacks the mitogenic properties of full-length CNTF, reducing proliferative risk

• Pregnancy or breastfeeding
• No established human safety profile — research use only
• Active CNS infections or inflammatory conditions

Store at 2–8°C (36–46°F) for up to 3 months. For long-term storage, keep at -20°C (-4°F). Once reconstituted, refrigerate and use within 14 days.

P21 was developed by Dr. Khalid Iqbal and colleagues at the New York State Institute for Basic Research in Developmental Disabilities. Published studies in Neurobiology of Aging (2011, 2013) demonstrated that P21 administration rescued cognitive deficits in Alzheimer's disease mouse models by promoting neurogenesis and reducing tau pathology. The peptide increased hippocampal neurogenesis by approximately 40-60% in aged mice and significantly improved performance in Morris water maze tests. It remains preclinical with no human trials completed.