Comparison

LL-37 vs Semax

Function

While LL-37 acts as a broad-spectrum antimicrobial and immunomodulatory peptide involved in host defense and wound repair, but can also promote inflammation and cancer cell proliferation in some contexts5215, Semax is used clinically in Russia for ischemic stroke and cognitive disorders; in models it improves learning, protects dopaminergic neurons, and modulates stress responses without significant endocrine ACTH-like effects166174.

Mechanism

While LL-37 works as a cationic amphipathic 37-amino-acid cathelicidin peptide generated from hCAP18 that disrupts microbial membranes and modulates innate immunity, including chemotaxis, cytokine induction, and NET formation521586, Semax is a synthetic heptapeptide, Met-Glu-His-Phe-Pro-Gly-Pro (MEHFPGP), that is an analog of ACTH(4–10) with a Pro-Gly-Pro extension and exerts neurotrophic and neuroprotective actions partly via upregulation of BDNF and modulation of dopaminergic and glutamatergic systems40162165174.

Length and Sequence

LL-37 is 37 amino acids long, whereas Semax is shorter as it has a length of 7 amino acids. LL-37 is made up of a sequence of Leucine, Leucine, Glycine, Aspartic acid, Phenylalanine, Phenylalanine, Arginine, Lysine, Serine, Lysine, Glutamic acid, Lysine, Isoleucine, Glycine, Lysine, Glutamic acid, Phenylalanine, Lysine, Arginine, Isoleucine, Valine, Glutamine, Arginine, Isoleucine, Lysine, Aspartic acid, Phenylalanine, Leucine, Arginine, Asparagine, Leucine, Valine, Proline, Arginine, Threonine, Glutamic acid, Serine. Semax is made up of a sequence of Methionine, Glutamic acid, Histidine, Phenylalanine, Proline, Glycine, Proline.

Receptor

LL-37

Functions as a ligand for CXCR2 on neutrophils and other myeloid cells; LL-37 signaling has also been linked to FPR2 and P2X7 in various cell types515

Semax

Targets are not fully defined; interacts with melanocortin-related pathways and inhibits certain peptidases, but no single dominant receptor has been established174

Organism or Origin

LL-37

Human cathelicidin antimicrobial peptide generated from the CAP-18 precursor5286

Semax

Synthetic analog of human ACTH(4–10) derived from POMC1748190

Gene

LL-37

CAMP

Semax

POMC

Related articles

No related articles are linked to these peptides yet.

Sources

52Cathelicidin LL-37: A new important molecule in the ... - PMC - NIH, https://pmc.ncbi.nlm.nih.gov/articles/PMC7388365/
86Cathelicidin antimicrobial peptide - Wikipedia, https://en.wikipedia.org/wiki/Cathelicidin_antimicrobial_peptide
40Semax ACTH(4-10) Analog Peptide ≥99% | VivePeptides, https://vivepeptides.com/product/semax/
81Proopiomelanocortin (POMC), the ACTH/melanocortin precursor, is ..., https://pmc.ncbi.nlm.nih.gov/articles/PMC2253185/
90alpha-Melanocyte stimulating hormone: production and degradation, https://pmc.ncbi.nlm.nih.gov/articles/PMC3936413/
162Semax 0.1% 10 mg | SEMAX POLAND, https://semaxpolska.com/en/semax-01-10-mg/
166The neuroprotective effects of Semax in conditions ..., https://pubmed.ncbi.nlm.nih.gov/15341218/
170Semax, https://pubchem.ncbi.nlm.nih.gov/compound/Met-Glu-His-Phe-Pro-Gly-Pro
171Semax peptide - NovoPro Bioscience Inc., https://www.novoprolabs.com/p/acth4-10-317047.html
174Semax - Wikipedia, https://en.wikipedia.org/wiki/Semax