LL-37 (Cathelicidin) vs P21
A detailed comparison to help you understand the differences and choose the right peptide for your research goals.
LL-37 (Cathelicidin)
LL-37 is the only human cathelicidin antimicrobial peptide. It plays crucial roles in innate immunity and has shown diverse biological activities including antimicrobial, immunomodulatory, and wound healing properties.
Full details →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 →Side-by-Side Comparison
| Aspect | LL-37 (Cathelicidin) | P21 |
|---|---|---|
| Mechanism | Disrupts bacterial membranes, neutralizes endotoxins, modulates immune cell function, and promotes wound healing. Has both direct antimicrobial and immunomodulatory effects. | Inhibits glycogen synthase kinase-3β (GSK-3β) and activates CREB signaling pathway. This promotes BDNF expression, neurogenesis in the hippocampus, and synaptic plasticity. |
| Typical Dosage | Research protocols vary widely. Typical ranges: 50-200mcg administered subcutaneously 2-3 times weekly. Some protocols use higher doses for acute infections. | Research protocols typically use 1-5mg administered intranasally or subcutaneously. Often used in cycles of 2-4 weeks. |
| Administration | Subcutaneous injection. Can cause significant injection site reactions. Often used in conjunction with other immune-supporting protocols. | Can be administered intranasally for direct CNS access or subcutaneously. Best used cyclically rather than continuously. |
| Side Effects | Injection site pain and reactions are common. May cause flu-like symptoms, temporary fatigue, or immune activation responses. | Limited data. Reported effects include mild headache, temporary brain fog during initial use, and fatigue. |
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