Research Background

Semax: Background on an ACTH-Fragment Research Neuropeptide

A factual overview of the origin, structure, and research context of the synthetic heptapeptide Semax.

Published 2026-05-30 · 5 min read

Introduction

Semax is a synthetic heptapeptide that appears regularly in neurological research literature. This article provides a factual overview of its origin, structure, and the research context in which it is studied. It is intended solely as a laboratory reference and makes no statement regarding use in humans or animals.

Origin

Semax was first described by research groups studying short analogs of adrenocorticotropic hormone (ACTH). It is derived from the 4–7 fragment of ACTH, extended with a Pro-Gly-Pro sequence that the literature associates with improved stability against enzymatic degradation in laboratory conditions.

Structure

The reported sequence of Semax is Met-Glu-His-Phe-Pro-Gly-Pro, with a molecular weight near 813.9 g/mol. The C-terminal Pro-Gly-Pro extension is frequently highlighted in analytical discussions of the molecule's resistance to peptidase activity in vitro.

Neurological Research Context

In the research literature, Semax is studied in connection with neurotrophic signaling. Areas that published authors have investigated include the following, listed for reference only and without any implication of effect:

  • Expression of brain-derived neurotrophic factor (BDNF) in cultured-cell and laboratory-model studies.
  • Neurotrophin-related signaling pathways examined in in vitro systems.
  • Comparative studies alongside other short regulatory peptides such as Selank.

Analytical Characterization

Research-grade Semax is supplied lyophilized and characterized by reversed-phase HPLC for purity, with identity confirmed by mass spectrometry. FYH Peptides documents batch-specific HPLC purity on each Certificate of Analysis. The lyophilized peptide is handled following standard laboratory practice, including storage at −20 °C away from light and moisture.

Summary

Semax is a synthetic ACTH(4-7) analog heptapeptide referenced widely in in vitro and laboratory-model neurological research. The content above is a neutral research reference and does not describe or support any application in humans or animals.

Referenced research compound Semax 10mg · 99.92% HPLC View compound data →

Published Research

Selected peer-reviewed literature indexed on NCBI PubMed. Listed for laboratory reference only — FYH Peptides makes no claim regarding the conclusions of any cited author.

  1. 1. Therapeutic Peptides in Orthopaedics: Applications, Challenges, and Future Directions. Rahman OF, Lee SJ, Seeds WA · Journal of the American Academy of Orthopaedic Surgeons. Global research & reviews · 2026 PubMed · DOI
  2. 2. Pharmacological Aspects of Neuro-Immune Interactions. Tarasov VV, Kudryashov NV, Chubarev VN, et al. · Current pharmaceutical design · 2018 PubMed · DOI
  3. 3. Semax peptide targets the μ opioid receptor gene Oprm1 to promote deubiquitination and functional recovery after spinal cord injury in female mice. Liu R, Chen Y, Huang H, et al. · British journal of pharmacology · 2025 PubMed · DOI
  4. 4. ACTH-like Peptides Compensate Rat Brain Gene Expression Profile Disrupted by Ischemia a Day After Experimental Stroke. Filippenkov IB, Shpetko YY, Stavchansky VV, et al. · Biomedicines · 2024 PubMed · DOI
  5. 5. The peptide semax affects the expression of genes related to the immune and vascular systems in rat brain focal ischemia: genome-wide transcriptional analysis. Medvedeva EV, Dmitrieva VG, Povarova OV, et al. · BMC genomics · 2014 PubMed · DOI
For Research Use Only. This article is a neutral laboratory reference. It does not describe, recommend, or imply use of any compound in humans or animals, and is not medical, therapeutic, or dietary guidance. The FDA has not evaluated any compound discussed for safety or efficacy.