N-Acetyl Semax Amidate (NASA) is an enhanced derivative of Semax, a synthetic heptapeptide based on the ACTH(4-10) fragment. The acetyl and amide modifications significantly improve its stability, bioavailability, and blood-brain barrier penetration.
Structure & Modifications
Amino Acid Sequence: Ac-Met-Glu-His-Phe-Pro-Gly-Pro-NH2
The modifications include:
- N-terminal acetylation: Protects from aminopeptidase degradation
- C-terminal amidation: Protects from carboxypeptidase degradation
These extend the half-life from 2-4 hours to 6-12 hours and enhance CNS penetration.
Mechanism of Action
BDNF Upregulation
Semax rapidly elevates brain-derived neurotrophic factor (BDNF) and its receptor TrkB in the hippocampus, supporting neuroplasticity and memory formation.
Neurotransmitter Modulation
The peptide activates serotonergic and dopaminergic brain systems, contributing to mood enhancement and cognitive function.
Research Applications
- Cognitive Enhancement: Improved memory, attention, and learning
- Stroke Recovery: In 110 stroke patients, intranasal Semax improved motor skills
- Neuroprotection: Protection against oxidative stress and inflammation
Comparison to Regular Semax
| Property | Semax | NA-Semax Amidate |
|---|---|---|
| Half-life | 2-4 hours | 6-12 hours |
| Stability | Moderate | High |
| BBB penetration | Good | Enhanced |
| Potency | Baseline | 2-3x enhanced |
Regulatory Status
Semax is approved in Russia for clinical use. NA-Semax Amidate is designated for research purposes only in Western countries.