FGL

FGL (FG loop peptide) is a synthetic neuropeptide derived from NCAM sequences that promotes neural repair, neurotrophin signaling, and memory formation. It enhances learning via FGFR1 activation and is under investigation for cognitive impairment, Alzheimer’s, and ischemia recovery. Delivered intranasally, it bypasses the BBB and targets brain-specific pathways.

• Binds neural cell adhesion molecules (NCAMs)
• Activates FGFR1 signaling, enhancing LTP and memory
• Increases neurotrophin availability including BDNF and NGF
• Reduces apoptosis in neurons post-injury or stress

• unit: mcg

  low dose: 200

  frequency: 3–5x per week

  high dose: 800

  standard dose: 400

  administration route: Intranasal

• Recommended protocol: 3–5x weekly for 6–12 weeks. Repeat every 3–6 months based on cognitive goals.

common: ["Mild nasal irritation","Transient fatigue"]

warnings: ["Should be used under supervision in patients with neuropsychiatric disorders","Avoid high doses without guidance due to excitatory synaptic effects"]

long term: ["No long-term toxicity reported in animal studies; human data is limited"]

sequence: EVYVVAENQQGKSKA

half life: Estimated 30–60 minutes

degradation: Cleared enzymatically in brain and blood plasma

molecular weight: 1226.6

molecular formula: C57H98N18O12S

tissue specificity: Hippocampus, prefrontal cortex, and CNS synaptic sites

• The NCAM-derived peptide FGL facilitates long-term plasticity in the dentate gyrus in vivo.mechanismPMID 21508096 ↗
• A NCAM-derived peptide reduces neuropathological signs induced by Abeta25-35.preclinicalPMID 17223274 ↗
• NCAM-Peptide FGL Mobilizes Neural Stem Cells and Promotes Regenerative Capacity after Stroke.preclinicalPMID 27352075 ↗