The Science Behind Selank

Written by Johnathon Anderson, Ph.D., a research scientist specializing in regenerative medicine and serving as an Associate Professor at the University of California Davis School of Medicine 

What is Selank?

Selank is a peptide with potent anti-anxiety and memory properties. Selank is composed of seven amino acids, and is derived from the highly studied Tuftsin peptide, which itself is derived from the protein immunoglobulin G. (1) Tuftsin is a powerful peptide that regulates the immune system, and has been studies for its ability to modulate immune cells such as lymphocytes and leukocytes. (2) Tuftsin therapeutic properties led to the generation of several analogs aiming to enhance its regenerative effects. (3,4)

Does Selank Reach The Brain?

Selank is to reach the brain by cross the blood brain barrier via its PGP domain. Selank has an additional peptide fragment added on the end, consisting of a Pro-Gly-Pro (PGP) sequence. (5) This PGP sequence enhances Selank’s bioavailability within the central nervous system, allowing it to traverse the blood-brain barrier and interact with neurons and glial cells with remarkable efficiency. (6) Research on Selank suggests that it has strong potential as a therapeutic agent in various neurological applications such as anxiety, neurasthenia, and depression.

Does Selank Research Show an Effect on The Brain?

Selank affects the brain by providing a potent calming effect, as well as enhancement of memory.

Does Selank Research Show an Effect on BDNF and TrkB?

Selank effects BDNF and TrkB by increasing their gene expression levels in the central nervous system. Selank plays a transformative role in influencing the body's levels of brain-derived neurotrophic factor (BDNF) and TrkB, which are two proteins that are essential for the survival and growth of neurons, as well as glial cells. (3) This vital factor acts as a lifeline for our brain’s architecture, ensuring that the pathways for learning and memory remain vibrant and well-maintained.

Studies indicate that Selank boosts the levels of BDNF in an essential part of the brain critical for learning and memory formation, called the hippocampus. (3) The hippocampus is a brain region deeply intertwined with our memories and emotional responses, much like a master conductor orchestrating a symphony of thoughts and feelings. Evidence suggests the hippocampus plays a critical role in episodic memory. Episodic memory is our event-related memory of the 'what, where and when' memory system.

Does Selank Research Show an Effect on Serotonin?

Selank effects serotonin by modulating its gene expression levels in the brain. Selank may also have a significant impact on serotonin's downstream signaling pathways, the very circuits that modulate our mood and anxiety levels. Research conducted with murine models has shown promising signs that Selank can regulate serotonin receptor levels, potentially amplifying the effects of this mood-regulating neurotransmitter. (7) Together, these findings illuminate Selank’s potential as a novel therapeutic agent in mental health, suggesting it could be a key player in not just mood enhancement but also in shaping cognitive health and resilience.

Does Selank Research Show an Effect on Calming The Brain?

Selank has a strong calming effect on the brain. Selank's calming effects on the brain are derived from its ability to enhance the GABA signaling pathway. Gamma-aminobutyric acid (GABA) is an amino acid that serves as the primary inhibitory neurotransmitter in the brain and a key inhibitory neurotransmitter in the spinal cord.

GABA is often regarded as the brain's soothing balm. In one study, researchers analyzed the levels of 84 unique genes involved in brain function and neurotransmission. This study revealed that Selank may modulate the GABAergic system, essentially elevating the brain’s regulatory mechanisms for calm and composure. (7) By enhancing GABA receptor activity, Selank may amplify the effects of this crucial neurotransmitter, potentially leading to improved emotional stability and reduced feelings of tension.

Does Selank Research Show an Effect on Memory?

Selank significantly enhances memory and recall. In an intriguing clinical trial, 62 patients with high levels of anxiety were closely examined to investigate the therapeutic effects of Selank. Participants were treated either with Selank or a control drug, setting the stage for a compelling exploration of this peptide's effects. Remarkably, researchers discovered that Selank significantly raised the amount of tau leu-enkephalin, a powerful endogenous opioid. Enkephalins are known for their strong affinity for the delta-opioid receptor, in addition to the mu-opioid receptor, while displaying a weaker connection to the kappa-opioid receptor. (10) The delta-opioid receptor reduces persistent pain and improves negative emotional states, with several clinical trials assessing the effectiveness of delta-opioid agonist therapies in chronic pain and depression. This research indicates that Selank's possesses anti-anxiety properties, suggesting that it may provide a natural mechanism for easing distress and fostering a sense of calm.

In addition to these anxiolytic effects, a preclinical study revealed another layer of Selank's prowess. Researchers found that it enhanced memory performance with each treatment with Selank therapy in a preclinical study. Imagine each dose of Selank as a catalyst, igniting the brain's potential to retain and recall information more effectively. These findings not only underscore Selank’s promise as a multifaceted therapeutic agent but also highlight its potential role in reshaping the landscape of anxiety treatment and cognitive enhancement.

References

1. Kozlovskaya MM, Kozlovskii II, Val'dman EA, Seredenin SB. Selank and short peptides of the tuftsin family in the regulation of adaptive behavior in stress. Neurosci Behav Physiol. 2003 Nov;33(9):853-60. https://pubmed.ncbi.nlm.nih.gov/14969422/

2. Najjar VA. Tuftsin, a natural activator of phagocyte cells: an overview. Ann N Y Acad Sci. 1983;419:1-11. doi: 10.1111/j.1749-6632.1983.tb37086.x. https://pubmed.ncbi.nlm.nih.gov/6370072/

3. Inozemtseva, L. S., Karpenko, E. A., Dolotov, O. V., Levitskaya, N. G., Kamensky, A. A., Andreeva, L. A., & Grivennikov, I. A. (2008). Intranasal administration of the peptide Selank regulates BDNF expression in the rat hippocampus in vivo. Doklady biological sciences : proceedings of the Academy of Sciences of the USSR, Biological sciences sections, 421, 241–243. https://link.springer.com/article/10.1134/S0012496608040066

4. Semenova, T. P., kozlovskiĭ, I. I., Zakharova, N. M., & Kozlovskaia, M. M. "Peptide Selank Enhances the Effect of Diazepam in Reducing Anxiety in Unpredictable Chronic Mild Stress Conditions in Rats" Eksperimental'naia i klinicheskaia farmakologiia (2009) 72(4), 6–8 https://onlinelibrary.wiley.com/doi/10.1155/2017/5091027

5. Fridkin M, Stabinsky Y, Zakuth V, Spirer Z. Tuftsin and some analogs: synthesis and interaction with human polymorphonuclear leukocytes. Biochim Biophys Acta. 1977 Jan 24;496(1):203-11. https://www.sciencedirect.com/science/article/abs/pii/0304416577901295 https://pubmed.ncbi.nlm.nih.gov/576412/

6. Elena Filatova et al., GABA, Selank, and Olanzapine Affect the Expression of Genes Involved in GABAergic Neurotransmission in IMR-32 Cells. https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2017.00089/full

7. Volkova, A., Shadrina, M., Kolomin, T., Andreeva, L., Limborska, S., Myasoedov, N., & Slominsky, P. (2016). Selank Administration Affects the Expression of Some Genes Involved in GABAergic Neurotransmission. Frontiers in pharmacology, 7, 31. https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2016.00031/full

8. T.A Kolomin et al., Transcriptomic Response of Rat Hippocampus and Spleen Cells to Single and Chronic Administration of the Peptide Selank. June 2, 2009. https://link.springer.com/article/10.1134/S1607672910010023

9. Zozulia AA, Neznamov GG, Siuniakov TS, Kost NV, Gabaeva MV, Sokolov OIu, Serebriakova EV, Siranchieva OA, Andriushenko AV, Telesheva ES, Siuniakov SA, Smulevich AB, Miasoedov NF, Seredenin SB. Efficacy and possible mechanisms of action of a new peptide anxiolytic selank in the therapy of generalized anxiety disorders and neurasthenia. Zh Nevrol Psikhiatr Im S S Korsakova. 2008;108(4):38-48 https://pubmed.ncbi.nlm.nih.gov/18454096/

10. Medvedev VE, Tereshchenko ON, Israelian AIu, Chobanu IK, Kost NV, Sokolov OIu, Miasoedov NF. A comparison of the anxiolytic effect and tolerability of selank and phenazepam in the treatment of anxiety disorders. Zh Nevrol Psikhiatr Im S S Korsakova. 2014;114(7):17-22 https://pubmed.ncbi.nlm.nih.gov/25176261/

11. Kozlovskii II, Danchev ND. The optimizing action of the synthetic peptide Selank on a conditioned active avoidance reflex in rats. Neurosci Behav Physiol. 2003 Sep;33(7):639-43. https://link.springer.com/article/10.1023/A:1024444321191