What is Semax?
Understanding an ACTH-derived peptide investigated in neurobiology, cognition and neurotrophic signalling.
Semax is a synthetic peptide derived from a fragment of adrenocorticotropic hormone (ACTH 4–10) with the addition of a Pro-Gly-Pro sequence to improve stability. Researchers have investigated Semax in relation to cognition, neuroplasticity, brain-derived neurotrophic factor (BDNF), cerebral physiology and neuronal signalling. Much of the published evidence comes from laboratory studies and relatively small clinical investigations, meaning further high-quality research is required to clarify its mechanisms and potential applications.
Quick Answer
Semax is a synthetic ACTH-derived heptapeptide primarily studied for its effects on neurobiology, cognition, neurotrophic factors and neuronal signalling. Researchers investigate its influence on BDNF, NGF, learning, memory and cerebral physiology in both laboratory and clinical settings.
Table of Contents
- What is Semax?
- Where does Semax come from?
- How does Semax work?
- What are neurotrophic factors?
- Why is Semax being researched?
- Current areas of scientific research
- Semax and Selank: what is the difference?
- Frequently Asked Questions
- References
What is Semax?
Semax is a synthetic peptide developed from the ACTH (4–10) fragment.
Its amino acid sequence is:
Met-Glu-His-Phe-Pro-Gly-Pro
Researchers modified the naturally occurring ACTH fragment by adding Pro-Gly-Pro, increasing resistance to enzymatic degradation and improving stability.
Semax has become one of the most widely studied neuroactive peptides because of its potential influence on neuronal signalling rather than endocrine hormone release.
Current research includes:
- Cognitive biology
- Learning and memory
- Neuroplasticity
- Neurotrophic signalling
- Cerebral physiology
- Stroke models
- Gene expression
- Neuroprotection
Where Does Semax Come From?
Semax originates from the naturally occurring hormone adrenocorticotropic hormone (ACTH).
ACTH is produced by the anterior pituitary gland and plays an important role in regulating adrenal hormone production.
Rather than using the full ACTH molecule, researchers isolated the biologically interesting ACTH (4–10) fragment before adding Pro-Gly-Pro to create the more stable synthetic peptide now known as Semax.
Unlike full-length ACTH, Semax has been investigated primarily for neurological rather than endocrine effects.
How Does Semax Work?
Semax appears to influence several interconnected biological pathways.
Neurotrophic signalling
One of the most studied areas is its relationship with brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF).
Experimental studies have reported changes in the expression of these neurotrophic factors following Semax administration, suggesting a role in neuronal maintenance and synaptic plasticity.
Gene expression
Research has shown that Semax can alter the expression of genes associated with neuronal function, inflammation and synaptic signalling.
Neurotransmitter systems
Investigators have also explored interactions with:
- Dopaminergic pathways
- Serotonergic signalling
- Glutamatergic transmission
- Cholinergic systems
Although these findings remain under investigation, they illustrate why Semax continues to attract interest in neuroscience research.
What are Neurotrophic Factors?
Neurotrophic factors are proteins that support the survival, growth and maintenance of neurons.
Two of the most studied include:
- BDNF (Brain-Derived Neurotrophic Factor)
- NGF (Nerve Growth Factor)
Researchers investigate these molecules because they influence:
- Learning
- Memory
- Synaptic plasticity
- Neuronal development
- Recovery following neurological injury
Semax has been studied for its potential interaction with these signalling pathways.
Why is Semax Being Researched?
Researchers investigate Semax because of its broad activity within the central nervous system.
Current research includes:
- Learning and memory
- Cognitive performance
- Neuroplasticity
- Stroke models
- Neuroprotection
- Cerebral blood flow
- Gene expression
- Neurotrophic factors
- Recovery following neurological injury
Several clinical studies have also investigated Semax in neurological conditions, although larger international trials remain necessary to confirm many reported findings.
Current Areas of Scientific Research
Semax continues to be investigated in relation to:
Neurotrophic signalling
- BDNF
- NGF
- Synaptic plasticity
Cognitive biology
- Learning
- Memory
- Attention
- Information processing
Cerebral physiology
- Stroke models
- Cerebral circulation
- Recovery following neurological injury
Gene regulation
Research suggests Semax alters the expression of numerous genes involved in neuronal function and inflammation.
Neuroprotection
Experimental studies continue investigating mechanisms that may influence neuronal resilience following injury.
Semax and Selank: What is the Difference?
Although often discussed together, Semax and Selank originate from different biological systems.
Semax
Derived from ACTH.
Primarily researched for:
- Neurotrophic factors
- Cognition
- Memory
- Neuroplasticity
- Stroke research
- Cerebral physiology
Selank
Derived from tuftsin.
Primarily researched for:
- GABAergic signalling
- Anxiety-associated behaviour
- Stress responses
- Immune regulation
- Neuroimmune signalling
The two peptides are complementary in research but possess distinct biological origins and mechanisms.
Frequently Asked Questions
Is Semax naturally occurring?
No.
Semax is synthetic but was developed from the naturally occurring ACTH (4–10) fragment.
Does Semax affect ACTH hormone production?
Current evidence suggests Semax behaves differently from full-length ACTH and is primarily investigated for neurological rather than endocrine activity.
Why is Semax associated with BDNF?
Laboratory research has reported changes in BDNF expression following Semax administration, making neurotrophic signalling one of its principal research areas.
What does Semax mainly target?
Researchers primarily investigate Semax in relation to:
- Learning
- Memory
- Neuroplasticity
- BDNF
- NGF
- Cerebral physiology
Is Semax approved as a medicine in the UK?
No.
Semax is not licensed as a medicine in the United Kingdom.
Is Semax the same as Selank?
No.
Although both are neuroactive synthetic peptides, they have different amino acid sequences, biological origins and research focuses.
References
- Semax: A Peptide with Neuroprotective and Nootropic Properties — Ashmarin IP, et al.
- Effects of Semax on Brain-Derived Neurotrophic Factor Expression Following Cerebral Ischaemia — Dolotov OV, et al.
- Gene Expression Changes Induced by Semax in Experimental Brain Injury — Levitskaya NG, et al.
- Semax and Neurotrophic Regulation in Experimental Neurology — Kamensky AA, et al.