P21 vs Humanin
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 →Humanin
Humanin is a mitochondrial-derived peptide with potent cytoprotective effects. Discovered in 2001, it has shown promise in protecting against age-related diseases including Alzheimer's, cardiovascular disease, and diabetes.
Full details →Side-by-Side Comparison
| Aspect | P21 | Humanin |
|---|---|---|
| Mechanism | Inhibits glycogen synthase kinase-3β (GSK-3β) and activates CREB signaling pathway. This promotes BDNF expression, neurogenesis in the hippocampus, and synaptic plasticity. | Binds to IGFBP-3 and BAX, inhibiting apoptosis. Activates STAT3 signaling and enhances cellular survival under stress. Protects mitochondrial function and reduces oxidative stress. |
| Typical Dosage | Research protocols typically use 1-5mg administered intranasally or subcutaneously. Often used in cycles of 2-4 weeks. | Research protocols vary widely. Studies have used doses from micrograms to milligrams depending on the analog and route. HNG (S14G-Humanin) is a more potent analog. |
| Administration | Can be administered intranasally for direct CNS access or subcutaneously. Best used cyclically rather than continuously. | Subcutaneous or intraperitoneal injection in research. Various analogs exist with different potencies and stabilities. |
| Side Effects | Limited data. Reported effects include mild headache, temporary brain fog during initial use, and fatigue. | Limited human data. Generally well-tolerated in animal studies. May affect glucose metabolism. |
| Best For |
What They Have in Common
Both P21 and Humanin are commonly used for: