SNAP-8 (Acetyl Octapeptide-3)

What it is

SNAP-8 is a peptide made of 8 amino acids and belongs to a small family of cosmetic peptides whose best-known member is called Argireline. In the ingredient list it appears as Acetyl Octapeptide-3.

The name is no coincidence; it refers to what the molecule is meant to imitate. For a muscle to contract, the nerve cell has to release the messenger acetylcholine. To do this, small vesicles have to fuse with the cell membrane, and that is done by a protein complex, the SNARE complex. One of its components is called SNAP-25.

How it is supposed to work

SNAP-8 is modeled on a piece of SNAP-25 and is supposed to wedge itself in between so that fusion works less well. Less messenger means less muscle tension, means less facial expression, means fewer expression lines.

This is not by chance reminiscent of Botox, and that is also how it is sold. Botulinum toxin attacks the same complex, except that it literally cleaves SNAP-25, and it is injected directly into the muscle. SNAP-8 is supposed to do the same thing gently and from the outside.

Where the 63 percent comes from

The figure that appears everywhere is 63 percent wrinkle reduction in 28 days. It is very specific and very widespread: on manufacturer websites, in shops, in guides. What it lacks is a reference in a peer-reviewed journal. It comes from the raw material manufacturer’s product documentation.

The problem is not lying; the problem is that it cannot be verified. One review describes the whole field like this: the majority of available clinical studies were conducted by the raw material suppliers to generate advertising claims and are usually not published in peer-reviewed journals; in addition, the methods used are often not disclosed. The same paper states that for most of these peptides there are no randomized studies at all showing an anti-aging effect in the scientific literature. For SNAP-8 itself it cites no efficacy study whatsoever. It appears in the list of mechanisms of action, nothing more.

The problem before the efficacy problem

Even if the molecule works perfectly in the test tube, it first has to get there. The target site is the junction between nerve and muscle, and it lies beneath the skin. In front of it lies the stratum corneum, built to keep water-soluble molecules out. Peptides are large, charged and water-loving, roughly the opposite of what gets through easily.

How little gets through is revealed by a figure from the scientific literature: microneedles increase the uptake of one of these peptides fortyfold compared with passive diffusion, that is, simple application. Accordingly, the literature on these peptides revolves around carrier systems, nanoliposomes, fatty acid attachments and microneedles — all tricks to make penetration possible in the first place. You do not call a locksmith when the door is open.

What the studies show

Argireline — the best study in the substance class

For the better-known relative there are the most presentable data in this substance class. One study found 30 percent less wrinkle depth after 30 days, compared with 10 percent under placebo. That sounds good until you read the number of participants: 10 women. This is not the worst study in this field, but the best.

The review of the field

A peer-reviewed review puts the data on cosmetic peptides into context: most clinical studies come from the raw material suppliers, serve to generate advertising claims and are not published in peer-reviewed form; the methods are often not disclosed. According to the review, for most of these peptides there are no randomized studies on anti-aging effects. SNAP-8 appears there only in the list of mechanisms of action, without its own efficacy study.

Microneedles — fortyfold uptake

A review reports that microneedles increase the uptake of one of these peptides fortyfold compared with simple application. The figure is meant as evidence of efficacy, but above all it says something about the normal case: how little gets through without needles.

Where the figure comes from — and where it does not

A controlled, peer-reviewed study on SNAP-8 alone cannot be found. The 63 percent is a manufacturer claim, and what has been published on this substance class at all depends on very small groups. So the question is not only whether SNAP-8 works, but how anyone would know.

It is also unclear how much reaches the target site at all. The entire line of research on carrier systems and microneedles is an indirect admission that passive application gets little through. Finally, for injected use: there is no study on it. Not one.

Status, approval and legal

As a cosmetic ingredient, SNAP-8 is permitted and can be found in ordinary creams, right down to the drugstore. Legally there is nothing questionable about that. Something completely different is its sale as a so-called research peptide, as a powder for dissolving and injecting: the substance was never developed, never tested and never approved anywhere for that purpose.

Safety

As a cream, SNAP-8 is cosmetically safe. It is applied externally and hardly enters the body, and that is precisely the problem with its efficacy. The question here is not what you risk, but what it costs. With injection, this tips over for 3 reasons. First, the substance has been tested as a cosmetic raw material for application on the skin; what it does in the body when injected has not been studied by anyone. Second, cosmetic purity does not mean injection purity, because sterility and endotoxins are not tested at all for a substance meant for the skin. Third, the mechanism of action is the blocking of nerve-to-muscle transmission. On the skin, almost none of it arrives, and that is the criticism. Under the skin, at an unknown site and in an unknown amount, that would be exactly the point where you do not want it.

Sources

• Review of cosmetic peptides (state of the data, manufacturer studies, disclosure of methods)
• Raw material manufacturer’s product documentation on SNAP-8 (63 percent in 28 days)
• Blanes-Mira et al., Int J Cosmet Sci 2002 (clinical study on Argireline, 10 female participants, 30 days)
• Review on skin penetration and the fortyfold uptake via microneedles