FG Loop
Also known as: FGL, NCAM peptide
Molecular Identifiers
Overview
Peptide derived from neural cell adhesion molecule (NCAM). Activates FGFR receptors, promoting synaptic plasticity and neuroprotection. Researched for cognitive enhancement, neural recovery, and neurodegenerative diseases.
Interest around FG Loop lies in its neuroplastic potential: FGFR activation, support of long-term potentiation (LTP), neuroprotection against excitotoxicity, and mimicry of NCAM function in neural signaling. Current evidence is mostly preclinical in models of memory, cerebral ischemia, and neurodegenerative disease, with no proven clinical cognitive efficacy in humans.
FG Loop has no regulatory approval from any agency and is classified as a research peptide. There is no established clinical prescription; when used outside academic settings, it is typically obtained via compounding pharmacies or research suppliers, in short subcutaneous cycles. There is no athletic indication or defined WADA status.
EVYVVAENQQGKSKA Glu-Val-Tyr-Val-Val-Ala-Glu-Asn-Gln-Gln-Gly-Lys-Ser-Lys-Ala Research peptide — sequence derived from the FG loop of neural cell adhesion molecule (NCAM)
Half-life
~1-3 hours
Administration Route
Subcutaneous
Category
Cognitive & Neuroprotective
Mechanism of Action
- Activation of FGFR receptors (fibroblast growth factor receptor)
- Promotion of synaptic plasticity and long-term potentiation (LTP)
- Neuroprotection against excitotoxicity and oxidative stress
- Mimicry of NCAM function in neural signaling
- Support for neuronal survival and differentiation
Dosage Protocol
Data compiled from the literature. This does not constitute medical advice.
| Parameter | Value |
|---|---|
| Dose | 25-200 mg intranasal (single ascending dose Phase 1) |
| Frequency | Single dose (tolerability study) |
| Timing | Not established — single-dose study |
| Duration | Not established — only single-dose Phase 1 in humans |
Reported Side Effects
Adverse effects described in the literature. Severity and frequency vary between individuals.
- Injection site pain
- Mild headache
Product Properties
| Purity | >98% |
| Appearance | White lyophilized powder |
| Solubility | Soluble in water and bacteriostatic water |
| Source | Solid-phase peptide synthesis (SPPS) |
| Storage | Lyophilized: -20°C for up to 2 years, 2-8°C for up to 6 months. Reconstituted: 2-8°C for up to 4 weeks. Protect from light and moisture. Avoid repeated freeze-thaw cycles. |
Presentations & Preparation
Vials of FG Loop found in the research market:
Reconstitution
- Diluent: Bacteriostatic water
- Volume: 2 ml per vial
- Inject the diluent slowly against the vial wall
- Gently swirl until fully dissolved
- Never shake
Storage
- Lyophilized: Refrigerated 2-8°C
- Reconstituted: Refrigerated 2-8°C (up to 30 days)
- Protect from direct light
- Do not freeze after reconstitution
Scientific Studies
Published studies on FG Loop.
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