Selank is a compound originally produced in Russia, with the goal of treating anxiety and potentially even improving certain cognitive functions, such as learning and memory. However, the actual research behind this drug is still in an extremely early stage, and most of the claimed benefits have not been confirmed or validated by independent studies in healthy human users. So what does the actual science behind this supposedly “nootropic” drug have to say? Read on to learn more about Selank, how it might work, and some of its possible effects in animal models.
The recent boom in biotechnology has opened the door for studying new biologically-active compounds, including “cognitive enhancers” or “nootropics.” One such compound is Selank — previously known as “TP-7” — which belongs to a class of molecules called synthetic peptides, or small artificially-designed proteins. Selank has been touted as an “anti-anxiety” compound, and has also been claimed to improve learning and increase energy — supposedly without side-effects or the risk of addiction.
Selank is small and only a fraction of the size of most naturally-occurring proteins. It was developed at the Institute of Molecular Genetics (Russian Academy of Sciences) in cooperation with the V.V. Zakusov Research Institute of Pharmacology (Russian Academy of Medical Sciences), along with its “cousin” drug, Semax. Selank was derived by combining the sequence of a peptide called tuftsin with another sequence that improves its molecular stability. Tuftsin is naturally-occurring, and makes up one part of the natural antibody IgG. Both tuftsin and Selank have been reported to reduce anxiety and increased serotonin levels in rats, with Selank being slightly more effective.
Selank has been approved in Russia for the treatment of generalized anxiety disorder (GAD) and for its use as a nootropic. However, the FDA has not approved its use for any conditions. Nonetheless, Selank continues to be available in several countries, where it is often sold as a “nutritional supplement.”
Mechanism of action
Although the mechanisms behind Selank are not yet fully known for certain, Selank is believed to act in part by stabilizing enkephalins in the blood. Enkephalins are natural peptides in the body that are believed to counteract the stress response. However, one animal study in mice did not demonstrate the stabilization of enkephalins following dosing with Selank, and the treated mice also did not appear to benefit from any significant “anti-anxiety” effects. According to some cell studies, Selank may bind to GABA receptors. By extensions, most compounds that bind to GABA receptors generally cause “sedative” effects. In one study of mice treated with Selank, researchers reported increased activity in inhibitory neurons, which rely on GABA. This resulted in less overall brain activity, which is generally consistent with a sedative effect.
In addition, some researchers have reported an increase in BDNF, an important brain-growth compound (neurotropic factor) which has been implicated in learning and memory. Some researchers have suggested that this mechanism may be responsible for some of Selank’s claimed cognitive effects.
Selank has also been reported to influence the levels of the neurotransmitters norepinephrine, dopamine, and serotonin in mice. These neurotransmitters are widely believed to be involved in motivation, focus, and pleasure. However, according to one animal study in mice, Selank was reported to increase norepinephrine, but reportedly decreased dopamine and serotonin levels. In contrast, in some other treated mice, Selank was reported to increase norepinephrine and dopamine levels, and did not change serotonin. Therefore, its exact effects and mechanisms remain unclear.
Uses and Effects of Selank
According to one preliminary clinical trial on 62 people, those given Selank reported fewer anxiety symptoms, with a greater decrease being observed in those suffering from pre-existing anxiety disorders. In another trial, similar benefits were reported in 60 patients suffering from anxiety and phobias, with these effects lasting up to a week after the final dose. Additionally, in one study of 70 anxiety patients, Selank was reported to increase the effects of phenazepam (an anti-anxiety drug banned in some U.S. states for its recreational use), while also reportedly reducing its rates of negative side-effects (such as drowsiness and memory loss). In one animal study, Selank was reported to reduce anxiety in mice. The more anxious the mice were to begin with, the more significant the observed changes in their behavior after treatment. Additionally, Selank was reported to show “anti-anxiety” effects in one study of rats who received 4 weeks of daily treatment.
Although limited, some of the above evidence suggests that Selank may potentially help curb anxiety, although much more research will still be needed to confirm its effectiveness and safety in human users. If you suffer from anxiety, you could have a discussion with your doctor about whether taking Selank might help you — however, always remember that you should never take this supplement in place of what your doctor recommends or prescribes.
– Blood Flow
In one animal study of sedated cats, Selank was reported to decrease blood pressure by about 30% for up to 3 minutes. It also increased blood flow to the cats’ brain by about 24% for up to 10 minutes. While these preliminary findings are interesting in that they suggest that Selank may have some short-term cardiovascular effects on blood flow, the relatively short durations of these effects is hard to interpret, and may suggest that these effects are not strong or medically significant. Additionally, these were only observed in animals, and so whether these effects would be similar in healthy human users remains unclear.
– Alcohol Withdrawal
Anxiety is one of the more common symptoms involved in alcohol withdrawal. To mimic high alcohol intake, rats were given a 10% solution of ethanol (alcohol) as their sole drinking source for 24 weeks. Selank reportedly decreased the anxiety of these rats after a 48-hour alcohol withdrawal period.
– Preventing Weight Gain and Reducing Cholesterol
According to one animal study, rats who were fed a high-fat diet reportedly showed 35% less weight gain when treated with Selank. Additionally, total cholesterol levels for these rats were reportedly reduced by over 58%, and blood glucose levels were reduced by 23.5%.
– Inflammation in the Spleen
After treatment with Selank, the spleens of mice were reported to show increased levels of several inflammatory response genes, which may suggest some degree of protection against the harmful effects of inflammation.
– Immune Function
Selank reportedly increased IL-6 in blood cells collected from patients suffering from depression. IL-6 is an inflammatory protein that is believed to help fight off infections. Additionally, according to one cell-based study, Selank was reported to stimulate the release of interferons, which are anti-viral molecules. Selank has also been proposed to potentially protect cells against some viral infections. However, one animal study in mice infected with a virus did not report any anti-viral benefits from Selank treatment, which casts doubt on this potential use.
Dosage of Selank
Note: The information in this section contains information about the dosages reported by some of the early studies that have been done on Selank so far, or the “typical” doses reportedly used by people who are experimenting with personal use of this compound. The information below is not intended as a guide for personal use of Selank, as adequate data about its potency, safety, or overall effects in healthy human populations is not currently available.
Because Selank is not approved by the FDA for any conditions, there is no official dose or dosing guidelines.
Therefore, it is extremely important to always make sure to speak with your doctor before personally experimenting with Selank (or any other unknown or unregulated substance).
Users and supplement manufacturers have sometimes tried to establish “unofficial” doses or other guidelines for the use of Selank. However, these are based largely on trial and error from individuals who have personally experimented with this drug, and do not come from any valid, properly-controlled clinical studies in large samples of human users. Relatedly, as an insufficiently-researched substance, Selank’s overall safety is practically unknown.
You should consult your doctor about potential side-effects based on your health condition and possible drug or supplement interactions. Selank products are typically available as a 0.15% spray, which translates to approximately 75 μg (micrograms) of Selank per spray. According to its manufacturers, the unofficial “recommended” dosage is 2-3 sprays per dose, spread out over up to 3 doses per day (with a maximum total of 675 μg/day). For an adult weighing 67.5 kg (about 149 lbs.), this translates to about 0.01 mg Selank/kg body weight. By comparison, many animal studies in rats have reported using dosages of up to 0.3 mg/kg body weight, which is much higher. However, the effects and mechanisms of this drug are not necessarily the same in animals as they are in humans, and so very little can be concluded based on this comparison.
Limitation of usage
Altogether, while some of the early findings reported about Selank might seem encouraging, there is still much that remains to be learned about this substance, and any claims about it should be treated with a healthy dose of skepticism until much more additional research is done. Additionally, there are also a number of specific reasons to be skeptical about the future of Selank.
Firstly, despite the addition of a stabilizing protein sequence, the half-life of Selank is only two minutes (meaning that half of it is removed from circulation throughout the body every two minutes). In fact, Selank is entirely undetectable in the blood after just 10 minutes. Findings such as these cast considerable doubt on many of the other existing early studies of Selank in animals, which have often reported “effects” of Selank lasting for up to a week or more. This seems quite unlikely if the drug is essentially removed from the body after just a few minutes.
There is also extremely limited information about Selank’s effects and safety in human patients — in fact, there are only 3 published clinical studies on this compound available PubMed!
Another major concern is the lack of data about Selank’s potential side-effects, both in the short- and long-term. Many of the studies that have been conducted on this drug so far were very short-term (lasting 24 hours or less). Additional research using much more rigorous methods and much longer testing periods must be performed to discover the potential adverse side-effects that this drug may cause in humans and animals.
Another significant concern is that Selank cannot be taken orally because the stomach will digest it. Therefore, it must be either be injected directly under the skin, or inhaled through the nose. Some researchers have proposed that inhaling is probably more effective in actually delivering the drug to the brain — however, these more extreme dosing methods also open up many potential dangers (which, as we noted above, are almost entirely un-studied).
While Selank is purchasable in Russia, it still has a long road ahead before it becomes readily available in the US. Synthetic peptides require FDA approval in the US.
Lastly, all of the scientific findings discussed in this post have been published by scientists working directly for the Russian Academy of Sciences, who were also the developers of this drug in the first place! This means that nearly all of the studies have a significant conflict of interest, and should not be taken at face value until their reported findings are confirmed by other, independent investigators.