Research Only Cognitive & Nootropic

FGL Peptide

also known as: FGL, NCAM-derived FGL peptide, EVYVVAENQQGKSKA

A 15-amino-acid synthetic peptide derived from the second fibronectin-type-III module of NCAM, designed to mimic NCAM's interaction with FGFR1 and reproduce downstream neurogenic signaling. Preclinical cognition and neuroprotection data only; no human clinical trials; research-only.

A 15-residue peptide (EVYVVAENQQGKSKA) mimicking a binding motif of the second fibronectin type-III (F3) module of the neural cell adhesion molecule (NCAM). Designed by Elisabeth Bock's group (University of Copenhagen) to replicate NCAM's interaction with fibroblast growth factor receptor 1 (FGFR1). Preclinical studies report that FGL crosses the blood-brain barrier, activates FGFR1, promotes hippocampal neurogenesis, reduces amyloid-β induced neurotoxicity, and improves spatial learning in rodent models. No human clinical data. Research-chemical only.

Mechanism of action

Mimics a FGFR1-binding motif within the NCAM F3 module. Engages FGFR1 at the cell surface, triggering dimerization and autophosphorylation with downstream activation of the PLCγ, MAPK/ERK, and PI3K/Akt pathways. In preclinical studies this has been associated with increased adult hippocampal neurogenesis (as measured by BrdU incorporation in the dentate gyrus), reduced amyloid-β-induced hippocampal cell death, and improved performance in Morris water maze and fear conditioning paradigms. Mechanism is preclinically characterized but has never been validated clinically.

Primary uses

  • Cognitive enhancement research (preclinical only)
  • Alzheimer disease models (rodent)
  • Post-stroke neurogenesis research (rodent)

Typical dosing

Not established for human use

⚠ No human dosing established. Rodent studies commonly used 1–10 mg/kg subcutaneous or intranasal. Any human use would be entirely unregulated and unsupported by clinical evidence.

Regulatory status

Not FDA-approved. No registered human clinical trials. Circulates in the research-chemical grey market as a putative nootropic; any human use would be unapproved and unsupported by human safety data.

References

  1. [pubmed] Neiiendam JL, et al. "An NCAM-derived FGF-receptor agonist, the FGL-peptide, induces neurite outgrowth and neuronal survival in primary rat neurons." J Neurochem, 2004;91:920-935.
  2. [pubmed] Knafo S, et al. "The NCAM-derived peptide FGL facilitates the intermediate stage of synaptic consolidation and the induction of LTP in the rat hippocampal CA1." J Neurosci, 2005;25:8459-8466.
  3. [pubmed] Corbett NJ, et al. "FGL-peptide, an NCAM-derived agonist of FGFR1, reduces tau phosphorylation in rat hippocampus." PLoS One, 2013;8:e56047.

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Disclaimer

This entry is for educational purposes only and does not constitute medical advice. Dosing information reflects published regulatory or research data and is not a recommendation. Many compounds described here are not approved for human use in the United States. Consult a licensed medical professional before considering any peptide therapy.