P21 vs Exenatide
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 →Exenatide
Exenatide was the first GLP-1 receptor agonist approved in the US, derived from a compound found in Gila monster saliva. Available as Byetta (twice daily) and Bydureon (once weekly extended-release).
Full details →Side-by-Side Comparison
| Aspect | P21 | Exenatide |
|---|---|---|
| Mechanism | Inhibits glycogen synthase kinase-3β (GSK-3β) and activates CREB signaling pathway. This promotes BDNF expression, neurogenesis in the hippocampus, and synaptic plasticity. | Synthetic version of exendin-4, which activates GLP-1 receptors to enhance glucose-dependent insulin secretion, suppress glucagon, slow gastric emptying, and promote satiety. |
| Typical Dosage | Research protocols typically use 1-5mg administered intranasally or subcutaneously. Often used in cycles of 2-4 weeks. | Byetta: 5mcg twice daily for 1 month, then 10mcg twice daily. Bydureon: 2mg subcutaneously once weekly. |
| Administration | Can be administered intranasally for direct CNS access or subcutaneously. Best used cyclically rather than continuously. | Byetta: Inject within 60 minutes before morning and evening meals. Bydureon: Any time of day, with or without meals. Do not mix with insulin in same syringe. |
| Side Effects | Limited data. Reported effects include mild headache, temporary brain fog during initial use, and fatigue. | Nausea (especially initially), vomiting, diarrhea, dizziness, headache, and injection site reactions (particularly with Bydureon). |
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