01What is Semax?
Semax is a synthetic peptide based on the ACTH(4–7) fragment with an added Pro-Gly-Pro sequence. It was designed for peptide-signaling research without the full adrenal-stimulating activity of intact ACTH. It has international research and use history but is not FDA-approved in the United States.
02How does it work in research?
Proposed mechanisms include changes in neurotrophin expression, melanocortin-associated signaling, neurotransmitter systems, and broader gene-expression programs. Recent rat transcriptomic work found numerous altered genes after exposure, underscoring that Semax may produce network-level effects rather than one fully defined receptor mechanism.
03Why do researchers study it?
Researchers use Semax in cellular and animal models involving neural stress, ischemia-related pathways, neurotrophins, synaptic signaling, and transcriptomic responses. Model choice and timing matter because a short-lived peptide signal can lead to later gene-expression changes that differ across tissues.
04What sets it apart?
Semax is an ACTH-fragment analog engineered to separate peptide-signaling questions from the endocrine behavior of full-length ACTH. The added Pro-Gly-Pro segment changes stability and biological behavior, so findings about ACTH or other melanocortins cannot be transferred directly.