P21 vs Thymulin
A detailed comparison to help you understand the differences and choose the right peptide for your research goals.
P21
P21 is a synthetic peptide derived from Cerebrolysin, specifically designed to mimic the neurotrophic effects of the parent compound. It promotes neurogenesis and has shown cognitive-enhancing properties in research.
Full details →Thymulin
Thymulin (Facteur Thymique Sérique) is a zinc-dependent nonapeptide hormone produced by thymic epithelial cells. It plays important roles in T-cell differentiation and immune system maturation.
Full details →Side-by-Side Comparison
| Aspect | P21 | Thymulin |
|---|---|---|
| Mechanism | Inhibits glycogen synthase kinase-3β (GSK-3β) and activates CREB signaling pathway. This promotes BDNF expression, neurogenesis in the hippocampus, and synaptic plasticity. | Requires zinc for biological activity. Promotes T-cell differentiation, modulates cytokine production, and influences neuroendocrine function. Levels decline significantly with age. |
| Typical Dosage | Research protocols typically use 1-5mg administered intranasally or subcutaneously. Often used in cycles of 2-4 weeks. | Research protocols vary. Often studied alongside zinc supplementation. Typical research doses in the microgram range. |
| Administration | Can be administered intranasally for direct CNS access or subcutaneously. Best used cyclically rather than continuously. | Subcutaneous or intramuscular injection in research settings. Requires adequate zinc status for activity. |
| Side Effects | Limited data. Reported effects include mild headache, temporary brain fog during initial use, and fatigue. | Limited data on exogenous administration. Theoretical effects on immune function require monitoring. |
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