▶ SEMAX · SUBTOPIC · MECHANISM
SEMAX Mechanism
For Laboratory Research Use Only. The mechanistic information below is descriptive of published research. No human dose is recommended. No clinical claim is made.
MECHANISM OF ACTION
Synthetic heptapeptide Met-Glu-His-Phe-Pro-Gly-Pro · analog of ACTH(4-10) extended with a stabilizing Pro-Gly-Pro tail. Upregulates BDNF and TrkB in rat hippocampus and basal forebrain.
PHARMACOKINETIC HALF-LIFE
Reported half-life for SEMAX: Short (minutes) plasma; intranasal CNS retention longer. Half-life determines the kinetic window across which receptor occupancy is maintained and frames the dosing rhythm used in published literature.
PRIMARY SEQUENCE
SEMAX is a defined sequence: Met-Glu-His-Phe-Pro-Gly-Pro. Synthesis proceeds via solid-phase peptide synthesis with HPLC-verified identity confirmation.
MECHANISM CATEGORIES
SEMAX is tagged in 3 mechanism categories on GIGARESEARCH. Each category aggregates the broader pharmacology of related compounds.
Nootropic compounds act on canonical CNS pathways · BDNF / TrkB neurotrophic signaling, monoamine modulation, and GABAergic regulation. Russian-developed heptapeptides Semax and Selank are the most-studied research nootropics in the GigaCompounds catalog, both built on the same C-terminal Pro-Gly-Pro stabilizing strategy.
Neurotrophic signaling encompasses BDNF, NGF, and the broader neurotrophin family, acting through Trk receptor tyrosine kinases. BDNF / TrkB signaling drives synaptic plasticity, neuronal survival, and learning. Semax is the most-studied research neurotrophic peptide.
BDNF (Brain-Derived Neurotrophic Factor) is a 119-residue homodimeric neurotrophin acting through TrkB receptor tyrosine kinase. It drives synaptic plasticity, long-term potentiation, and neuronal survival in hippocampus, cortex, and basal forebrain. Semax upregulates hippocampal BDNF / TrkB expression in rodent models.
MECHANISTIC OUTCOMES IN LITERATURE
The following outcomes are the mechanistic endpoints reported in the peer-reviewed literature, with GIGARESEARCH evidence grades. Grades reflect study quality and replication, not clinical recommendation.
Dolotov et al. 2006 (Brain Res, PMID 16996037) showed 1.4–1.6× BDNF protein elevation in rat hippocampus after single 50 µg/kg intranasal dose; matched TrkB phosphorylation.
Dolotov et al. 2006 (J Neurochem, PMID 16635254) identified specific binding sites for tritium-labeled Semax in rat basal forebrain (KD ≈ 2.4 nM).
Russian clinical literature describes small trials in stroke recovery, optic-nerve atrophy, ADHD-spectrum behavior. No FDA/EMA Phase 3 trials.
MECHANISM Q+A
▶ How does Semax work?
Proposed mechanisms include upregulation of BDNF protein and mRNA in rat hippocampus and basal forebrain after intranasal administration, increased TrkB receptor phosphorylation (canonical signal-transduction event downstream of BDNF), and modulation of serotonin and dopamine turnover in rodent striatum and cortex.
▶ Does Semax cross the blood-brain barrier?
Intranasal Semax accesses the CNS through the olfactory bulb route, bypassing the blood-brain barrier. Specific binding sites have been identified in rat basal forebrain (Dolotov 2006, KD ≈ 2.4 nM).
▶ Is there Western peer-reviewed Semax literature?
Yes · primarily the Dolotov et al. series in Brain Res (PMID 16996037), J Neurochem (PMID 16635254), and Doklady Biol Sci (PMID 14556513). These are the most accessible Western-indexed Semax mechanism papers.
CITED LITERATURE
- Dolotov OV, Karpenko EA, Inozemtseva LS, et al.. Semax, an analog of ACTH(4-10) with cognitive effects, regulates BDNF and trkB expression in the rat hippocampus. Brain Res 2006. PMID 16996037. link
- Dolotov OV, Karpenko EA, Seredenina TS, et al.. Semax, an analogue of adrenocorticotropin (4-10), binds specifically and increases levels of BDNF in rat basal forebrain. J Neurochem 2006. PMID 16635254. link
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▶ LAST UPDATED · 2026-05-19