Semax

Semax is a lab-made peptide (a short chain of seven amino acids). It is built from a small piece of the hormone ACTH joined to an extra tail that helps it last longer. Unlike the full hormone, it does not act as a stress hormone. It is studied as a research peptide for protecting nerve cells and supporting thinking (a "nootropic," meaning something looked at for brain function).

How it works

Semax does not work through one single receptor. Research has reported that it attaches to and adjusts certain melanocortin-related docking sites in the brain [1] and, most notably, that it affects the system of proteins that help nerve cells grow and survive. Studies have described how Semax changes the amounts of two such proteins — BDNF (brain-derived neurotrophic factor, a protein that helps brain cells grow and survive) and NGF (nerve growth factor, a similar nerve-supporting protein) — and their docking sites in the rat brain [2][3].

Effects on BDNF and nerve protection

Several rat studies have looked at Semax and its added tail turning on the genes for these nerve-supporting proteins and their docking sites after a lab-created stroke (blocked blood flow to the brain) [4], and have tracked how BDNF and NGF levels change over time in memory and thinking parts of the brain [3]. This work outlines a possible nerve-protecting way of working in animal models.

What researchers have studied it for (behavior and thinking)

Semax has been described as a brain-piece peptide with thinking-related properties in animal studies [1], and rat work has reported antidepressant-like and anti-stress effects in an ongoing-stress model [5]. These are early behavior results in animals.

What the research hasn't shown yet

Human evidence is limited and comes mostly from regional stroke journals; solid, controlled proof that it is safe or works is not established here. This peptide is supplied for laboratory research use only and is not meant for use in people or animals.

In the laboratory, lyophilized Semax is commonly reconstituted with bacteriostatic or sterile water and mixed gently. Store the lyophilized powder at -20°C, keep reconstituted solution at 2-8°C, protect from light, and minimize freeze-thaw cycles to maintain peptide integrity.