Peptides- what are they?

These days, along with antioxidants, peptides have become a byword for antiaging skincare products. Matrixyl is probably the best known, but here seem to be new ones popping up all the time. So what are peptides, how do they work and why are we paying so much for them in our skin creams?

Peptides have the same chemical structure as proteins, but are shorter in length. They are made up of amino acids. In cosmetic ingredients lists you might have seen tripeptides, for example, or dipeptide. These different names refer to the number of amino acids. A dipeptide has two amino acids, tripeptide has three amino acids and a tetrapeptide has four amino acids. And so on.

Peptides, or mini proteins if you want to think of them that way, are active molecules that send signals to your cells. When collagen breaks down, it forms specific peptides that signal to your skin that it was damaged and needs to make new collagen. So by applying peptides topically, we are trying to trick our skin into thinking that it has lost collagen recently and needs to make more.

There are lots of different synthetic peptides available in antiaging skincare and they have many roles. Some of them appear in ingredients’ lists by a trade name such as Matrixyl or Argireline, and these might be a combination of more than one peptide.

Only very small amounts of are needed. They possess, if correctly chosen and formulated, very high biological potency. That means, according to Special Chem 4 Cosmetics, cosmetic effects can be obtained with very low quantities (only a few ppm compared to a retinol, which is used at 600-700 ppm level).

Here’s a run down of the most common cosmetic peptides, what they do and links to more reading:

Acetyl tetrapeptide-9. This is a relatively new peptide. There are protein-sugar (glycosaminoglycan chains) complexes that are involved with collagen fibers. And acetyl tetrapeptide-9 targets one in particular, called lumican that is involved in both the synthesis of collagen fibrils and their organization into functional fibers, ensuring the integrity of the extra-cellular matrix. This peptide is in Celazome N45.

Argireline – acetyle hexapeptide 3. This the best known of the neuropeptides (for more neuropeptides see below and also read our post on Botox in jar ingredients. It works by limiting the neurotransmitters that tell your facial muscles to move (a process known as exocytosis). Read more on Argireline.

Caprooyl tetrapeptide-3 (it also goes by the name ChroNOline).  A tetrapeptide is made up of four amino acids and, like all peptides, it signals our bodies to do things – like get busy and produce more collagem, for example. Unlike most peptides, caprooyl tetrapeptide-3 is derived from a growth factor. The caprooyl part is a lipid, which is supposed to increase stability and skin penetration. It is supposed to increase collagen lll by 34% as well as laminin production by 26% and laminin 5 by 49%.

Copper peptides. These are made by sticking copper to a GHK (see Matrixy 3000 below) peptide. Copper peptides heal wounds and stimulate hair follicles. Read more on copper peptides.

Hexapeptide-11 is derived from yeast. There isn’t much information on it. But I have read that test on human dermal fibroblasts show it can upregulate key genes responsible for collagen production and hyaluronic acid. It is also associated with hair growth. It may be able to upregulate the Androgen Receptor gene, binding to it. much the way testosterone will. This has led to speculation that hexapeptide-11 may be able to influence the principal biochemical pathways responsible for converting young velus hair into mature hair.

Matrixyl – palmitoyl pentapeptide. A pentapeptide has five amino acids. This is one of the best known and most ubiquitous collagen signaling peptides used in cosmetics. Palmitoyl pentapeptide stimulates the synthesis of the key constituents of the skin matrix - collagen, elastin and glucosamnoglycans. Read more on Matrixyl.

Matrixyl 3000 - palmitoyl-tripeptide and palmitoyl-oligopeptide. Supposedly a more potent version of Matrixyl because it has two peptides that work synergistically.

Myristoyl pentapeptide-8. This is supposed to be a collagen booster and it is increasingly showing up in eyelash growth products, such as Cilea, Glymed and CODE:ai. There is very little information on this peptide.

Palmitoyl oligopeptide (Pal-GHK) has three amino acids and is a GHK peptide or glycine-histidine-lysine.  GHK (see above for copper peptides) triggers the synthesis of collagen. The other peptide, palmitoyl-tripeptide, is believed to reduce the production of interleukins.  See our Five Best products with Matrixyl 3000.

Neuropeptides. In addition to Argireline (above) there are several other peptides that work as neurotransmitters. SNAP-8 is an octapeptide (eight amino acids), Myoxinol is oligopeptides taken from okra seeds, and Syn-Ake, which is dipeptide diaminobutyroyl. Read more on neurotransmitters.

Syn-tacks - palmitoyl dipeptide-5 diaminobutyroyl hydroxythreonine and palmitoyl dipeptide-6 diaminohydroxybutyrate.  These are meant to stimulate laminin V, collagen types IV, VII and XVII and integrin. Read more on Syn-tacks.

Tripeptide 1. This peptide is combined with wheat and soy proteins to by the name of Aldenine. Tripeptide 1 mimics the relationship of the growth factors involved in the healing process and synthesis of collagen. Specifically, it is supposed to stimulate the synthesis of collagen I and III, fibronectin and laminin. Tripeptide GHK is also an aldehyde sequestering agent that can capture (or scavenge) lipid peroxidation by-products. As a result it is also used for removing and preventing cellulite.