Semax

also known as: ACTH(4-7)PGP, methionyl-glutamyl-histidyl-phenylalanyl-prolyl-glycyl-proline

A synthetic ACTH-derived heptapeptide approved in Russia for stroke rehabilitation and optic nerve disorders, with documented BDNF upregulation and broad nootropic activity.

A 7-amino-acid stabilized fragment of ACTH(4-10) developed at the Institute of Molecular Genetics (Moscow) in the 1980s, with the C-terminal PGP extension conferring protease resistance and retaining the neurotrophic/nootropic activity without the corticotropic effect.

Mechanism of action

Multimodal: upregulates BDNF mRNA in the hippocampus within 30 minutes of intranasal administration; modulates dopaminergic and serotonergic signaling; inhibits enkephalin-degrading enzymes, producing mild opioidergic effects; demonstrates neuroprotective activity in ischemia models. Lacks ACTH-like corticotropic activity.

Primary uses

Stroke rehabilitation (Russian approval)
Optic neuropathy (Russian approval)
Cognitive enhancement during acute stress
Anxiety and mood research

Typical dosing

250–600 mcg 2–3 times daily (intranasal)

Russian clinical dosing: 0.1% solution, 2–3 drops per nostril, 2–3 times daily.

Regulatory status

Approved in Russia by the Ministry of Health as a medicine for stroke rehabilitation, optic nerve disorders, and cognitive enhancement during high-stress tasks. Not approved by the FDA or EMA.

References

[pubmed] Dolotov OV, et al. "Semax, an analog of adrenocorticotropin (4-10), binds specifically and increases levels of brain-derived neurotrophic factor protein in rat basal forebrain." J Neurochem, 2006;97 Suppl 1:82-86.
[pubmed] Myasoedov NF, et al. "Heptapeptide Semax and its neurotropic actions." Zh Vyssh Nerv Deiat Im I P Pavlova, 1999;49:646-652.
[pubmed] Gusev EI, et al. "Neuroprotective effects of Semax in acute ischemic stroke." Zh Nevrol Psikhiatr Im S S Korsakova, 2005;105:41-46.

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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.