N-Acetyl Semax

A foundational point for any rigorous reference to N-Acetyl Semax is that the published primary research base concerns the parent heptapeptide Semax, not the doubly-modified analog. The compound's chemical identity is catalogued at PubChem CID 172638603 (formula C39H54N10O10S; molecular weight 855.0 g/mol; CAS 2920938-90-3; HELM notation PEPTIDE1{[ac].M.E.H.F.P.G.P.[am]}). Dedicated peer-reviewed mechanism or efficacy studies on the acetylated-and-amidated molecule are essentially absent. The two primary studies that examined an N-terminally acetylated Semax specifically were chemistry-focused: Shevchenko et al. (2013, Doklady Biological Sciences) examined the proteolytic stability of acetylated Semax in various biological media, and Magrì et al. (2016, Journal of Inorganic Biochemistry) examined how N-terminal acetylation alters the copper(II) and zinc(II) coordination geometry and associated in-vitro properties. Both studied a form retaining a free C-terminal acid rather than the amide, so they represent the closest available primary data rather than an exact match to the displayed compound. The remainder of the research described below derives from the parent-Semax literature; extrapolation to N-Acetyl Semax is an inference, not a demonstrated equivalence.

The most developed slice of the Semax literature examined interactions with neurotrophin systems. Shadrina et al. (2001, Neuroscience Letters) used rat glial cell cultures from newborn basal forebrain to measure NGF and BDNF mRNA by PCR as a candidate route to neurotrophic activity. Dolotov et al. (2006, Brain Research) administered a single intranasal dose of Semax to rats and measured hippocampal BDNF protein, TrkB tyrosine phosphorylation, and exon-III BDNF/TrkB mRNA alongside a conditioned-avoidance behavioral task. A companion Dolotov et al. (2006, Journal of Neurochemistry) study used tritium-labeled Semax to characterize specific, reversible, calcium-dependent binding sites in rat basal forebrain membranes and measured regional BDNF protein, examining whether a receptor-mediated mechanism underlies neurotrophin effects. Shadrina et al. (2010, Journal of Molecular Neuroscience) profiled the temporal dynamics of NGF and BDNF gene expression across hippocampus, frontal cortex, and retina in rodents.

A substantial body of work examined Semax in rodent middle cerebral artery occlusion (MCAO) models. Dmitrieva et al. (2010, Cellular and Molecular Neurobiology) measured neurotrophin and receptor transcript levels (Bdnf, Ngf, Nt-3, TrkA/B/C) after permanent MCAO, contrasting Semax with its Pro-Gly-Pro fragment to distinguish sequence-specific from nonspecific effects. Medvedeva et al. (2014, BMC Genomics) and Medvedeva et al. (2017, Molecular Genetics and Genomics) applied genome-wide transcriptional profiling of ischemic rat cortex to catalogue biological-process-level gene-expression changes, with prominent immune-response and vascular gene categories. Filippenkov et al. (2020, Genes) used RNA-Seq in a transient MCAO model to enumerate differentially expressed genes under Semax treatment. Sudarkina et al. (2021, International Journal of Molecular Sciences) measured protein-level endpoints (MMP-9, c-Fos, JNK, CREB) by immunodetection in the ischemia-reperfusion model. Dergunova et al. (2021, Molecular Biology) used qRT-PCR to quantify proinflammatory mediator transcripts (Il1a, Il1b, Il6, Ccl3, Cxcl2) in the reperfusion context.

A separate research axis situated Semax within melanocortin and monoaminergic pharmacology. Eremin et al. (2005, Neurochemical Research) used tissue measurements and microdialysis in rodents to quantify striatal serotonin metabolite (5-HIAA) and dopamine dynamics, and measured how Semax pretreatment altered the neurochemical response to D-amphetamine and locomotor behavior. Inozemtseva et al. (2024, European Journal of Pharmacology) studied Semax in a chronic-unpredictable-stress rat model alongside a melanocortin agonist, measuring behavioral and stress-axis endpoints; this work also characterized Semax in the context of the melanocortin MC4 receptor and HPA-axis feedback.

Bioinorganic studies examined the Semax scaffold in metal-coordination and amyloid-interaction contexts. Magrì et al. (2016) characterized how N-terminal acetylation of Semax alters Cu(II)/Zn(II) coordination geometry and associated in-vitro properties — the study most directly relevant to the N-Acetyl Semax analog. Sciacca et al. (2022, ACS Chemical Neuroscience) and Tomasello et al. (2025, Bioinorganic Chemistry and Applications) examined Semax as a copper-binding peptide in membrane-model and SH-SY5Y neuroblastoma systems, measuring its effect on Cu(II)-catalyzed amyloid-β aggregation and reactive-oxygen-species production in vitro. Radchenko et al. (2025, Acta Naturae) used APPswe/PS1dE9 transgenic mice with behavioral testing (open-field, novel-object-recognition, Barnes maze) plus histology to examine Semax and a derivative in an Alzheimer's amyloidosis model. Liu et al. (2025, British Journal of Pharmacology) combined a mouse spinal cord injury model with a PC12 neuroinflammation model, applying RNA-Seq, network pharmacology, and molecular docking to probe candidate signaling nodes including the genes Oprm1 and USP18.

Clinical investigation has been conducted on the parent compound Semax only; no published or registered clinical trials exist for N-Acetyl Semax. Gusev et al. (2018, Zhurnal Nevrologii i Psikhiatrii) enrolled 110 post-ischemic-stroke patients divided into early and late rehabilitation timing groups and measured plasma BDNF, motor performance on the British Medical Research Council scale, and Barthel index as endpoints, using a non-randomized design. A Dergunova et al. (2023) review in Genes examined neuroprotective heptapeptide strategies, situating the parent compound in the broader landscape of ischemic-stroke research.