Ch.02, Peptides
Let's be honest, peptides can seem a bit more complex and harder to grasp compared to other skincare ingredients.
But here's the exciting part: these tiny molecules are the secret superheroes that are revolutionizing the world of skincare.
They have the ability to stimulate collagen production, smooth wrinkles, and restore skin firmness. In this chapter, we'll explore the different peptide types, delve into their science and mechanisms of action, and share practical tips for incorporating them into your skincare routine.
What are peptides?
Peptides are short chains of amino acids which are the building blocks of protein. Both peptides and proteins are made from amino acid sequences.
The difference is that a molecule made up of 2 - 50 amino acids is considered a peptide, and a molecule made up of 50 or more amino acids is considered a protein. Thanks to their smaller size, peptides possess the ability to penetrate the skin when applied topically (1).
You can think of peptides as little messengers to our skin cells, sending messages that stimulate processes your skin already performs on its own. In skincare, peptides have been shown to not only stimulate collagen production and inhibit its breakdown, but also to have antimicrobial, whitening, and antioxidant properties. Additionally, peptides enhance the absorption of other active ingredients, provide moisturizing effects, alleviate inflammation, and facilitate wound healing (2).
The 4 types of peptides
The distinct composition and arrangement of amino acids give rise to diverse types of peptides, each with its unique benefits and mechanisms of action on the skin (1). Broadly speaking, peptides can be classified into four main categories.
1. Signal peptides
Signal peptides sends signals - hence the name - to your skin to increase the production of proteins which in return can boost collagen and elastin production.
This type of peptide can trick your skin into thinking it is injured to activate regeneration processes such as the production of collagen, elastin, proteoglycan, and glycosaminoglycan. As a result, signal peptides in skincare can help reduce the appearance of fine lines and wrinkles, which is important to maintain smooth, wrinkle-free skin.
🔎📕 The most researched signal peptides include:
✔️ Palmitoyl pentapeptide-4 (Matrixyl®). This peptide has been reported to improve the appearance of fine lines, skin roughness, and wrinkle depth by stimulating elastin and collagen production (3,4).
✔️ Tetrapeptide-21 (GEKG). In a comparative study between Tetrapeptide-21 (GEKG) and Matrixyl®, it was found that GEKG demonstrated a 41.3% increase in skin elasticity, whereas Matrixyl® showed a slightly lower improvement of 35.6%.
Other popular, but less researched signal peptides include: Biopeptide ELTM (Palmitoyl Hexapeptide-12), Palmitoyl Tripeptide-1, palmitoyl tripeptide-5, palmitoyl tetrapeptide-7, and palmitoyl oligopeptide (2,3).
2. Carrier peptides
Carrier peptides transport or carry mineral ions like manganese and copper to your skin cells to boost processes such as collagen and elastin production.
In the skin, copper is essential for collagen and elastin formation during normal skin renewal and wound healing. On the other hand, manganese is mainly involved in skin defense against UV radiation.By facilitating the delivery of mineral ions to the skin cells, carrier peptides therefore enhance essential skin functions, resulting in improved collagen and elastin production, protection against UV radiation, and optimal hydration.
Hence, incorporating products containing these carrier peptides into your skincare routine can contribute to a healthier, more youthful complexion.
🔎📕 The most researched carrier peptides are:
✔️Copper tripeptide (Cu-GHK). In the 1970s, Dr. Loren Pickart, a renowned biochemist, discovered the potential benefits of copper peptides for skincare. His research focused on the role of copper in the body and its effects on wound healing. Through his studies, he observed positive effects of copper peptides on skin regeneration and rejuvenation.
Since their discovery, copper peptides have gained considerable recognition in the cosmetic industry. They are widely utilized to enhance various aspects of skin health, including promoting skin cell proliferation, firmness, elasticity, and thickness. Copper peptides have also been found to aid in reducing hyperpigmentation (3, 5).
In a study involving a small sample size of 20 women, copper peptides showed an increase in new collagen production in 70% of the participants. This outcome surpassed the results observed with vitamin C (50%) or Tretinoin (40%). Additionally, other studies involving approximately 180 participants demonstrated that copper peptides, when incorporated into eye and facial creams, helped reduce visible signs of photo-damaged and aged skin. Specifically, they stimulated collagen synthesis and contributed to increased skin density and thickness (1,2,3).
3. Neurotransmitter inhibitor peptides
Similar to botox, this category of peptides work by inhibiting the signals that causes muscles to contract.
Every time you make a voluntary or involuntary facial expression, such as frowning or smiling, neurotransmitters are released and bind to appropriate receptors to trigger muscle contraction. True to their name, neurotransmitter inhibitor peptides, use different mechanisms to partially block these signals that trigger muscle contractions.
As a result, these types of peptides are used in skincare to reduce fine lines and wrinkles. Having said that, they are not nearly as potent as actual botox.
🔎📕 The most researched neurotransmitter inhibitor peptides are:
✔️Argireline (Acetyl Hexapeptide-3). In studies, this peptide has demonstrated its ability to reduce wrinkle depth and improve skin texture (2, 4).
Other popular, but less researched neurotransmitter inhibitor peptides include: Vialox® (Pentapeptide-3), Leuphasyl® (Pentapeptide-18), and Tripeptide-32.3.
4. Enzyme inhibitor peptides
Enzyme inhibitor peptides work by blocking the activity of certain skin enzymes that contribute to the breakdown of structural proteins, such as collagen and elastin, as well as the formation of melanin.
By inhibiting enzymes such as collagenase, elastase and tyrosinase, enzyme inhibitor peptides can help maintain skin firmness and address issues related to hyperpigmentation. There are various types of enzyme inhibitor peptides used in skincare, each with its own unique properties and benefits. The most popular ones derive from soybean, silk fibroin, black rice and fruits.
❗While enzyme inhibitor peptides show promise, it's important to note that the extent of their effectiveness is still uncertain. Limited human studies or a lack thereof makes it challenging to fully ascertain their true relevance and benefits in skincare. Further research is needed to determine the true potential and efficacy of these peptides in addressing specific skin concerns (2).
By now you are probably wondering which type of peptide you should choose. Over the years, numerous peptides have been developed and incorporated into cosmetic products. However, it's important to note, that for many of them, studies supporting their effectiveness are limited and not well-established. To enhance the likelihood of positive outcomes, consider peptides that have demonstrated effectiveness through independent clinical studies. The most notable of these are:
| Peptide | Research |
|---|---|
| Copper peptides (Cu-GHK) | ★★★ |
| Palmitoyl pentapeptide-4 (Matrixyl®) | ★★★ |
| Tetrapeptide-21 (GEKG) | ★★ |
| Acetyl hexapeptide-3 (Argireline®) | ★★ |
How to use peptides
Including Vitamin C in your skincare routine can be a little tricky, so here are some tips on how to use it correctly:
Apply AM & PM
The great news is that peptides don't cause any sensitization to the sun, making them suitable for both day and night use. You can confidently incorporate peptides into your skincare routine without worrying about sun exposure.
Choose right format
When selecting a peptide product, opt for ones that can absorb into your skin effectively. Creams, lotions, and serums are usually your best bet. Avoid face washes that are quickly rinsed off, as they do not allow enough time for the peptides to penetrate.
Be patient & consistent
Long-term and consistent use of peptides is necessary to see noticeable results. It's important to understand that changes won't happen overnight but over weeks and months.
Cleanse and apply
To maximize the penetration of peptides into your skin, apply your peptide cream or serum right after cleansing. This allows the peptides to have direct contact with your skin before layering on your moisturizer.
Peptides’ friends
Although the benefits of peptides are not enhanced through certain combinations they can favorably be paired with other known active ingredients such as hyaluronic acid and niacinamide to avail their respective benefits.
Peptides’ enemies
Peptides don't always get along with certain acids. Avoid mixing peptides with alpha hydroxy acids (AHAs) like glycolic and lactic acid, or beta hydroxy acids (BHAs) like salicylic acid. These acids can break down peptides, rendering them less effective. Similarly, avoid layering copper peptides specifically with vitamin c or retinoids. Instead, use them in alternating routines to enjoy the benefits of both.
CHEAT SHEET
Peptides are formed from short amino acid sequences that act as tiny messengers to our skin cells, sending messages that stimulate and enhance processes that your skin already performs on its own.
The specific composition and arrangement of amino acids result in different types of peptides with specific benefits and mechanisms of action.
Broadly speaking there are 4 groups of peptides:
Signal peptides: send messages to skin cells, stimulating processes such as collagen and elastin production.
Carrier peptides: transport essential minerals, like copper to skin cells which can promote collagen synthesis, antioxidant protection, and improve skin hydration.
Neurotransmitter inhibitor peptides: similar to botox, they reduce facial muscle contractions, minimizing fine lines and wrinkles.
Enzyme inhibitor peptides: block the action of specific enzymes involved in the breakdown of structural proteins and melanin formation.
To enhance the likelihood of positive outcomes, consider peptides that have demonstrated effectiveness through independent clinical studies. The most notable of these are:
Copper peptides (Cu-GHK)
Palmitoyl pentapeptide-4 (Matrixyl®),
Tetrapeptide-21 (GEKG)
Acetyl hexapeptide-3 (Argireline®)
Questions & Answers
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It depends. Most peptides can work synergistically with Vitamin C (L-ascorbic acid) to improve skin appearance and boost collagen production (7). However, be careful when using copper peptides. Copper can oxidize ascorbic acid and cause it to break down rapidly, thus blocking the benefits of Vitamin C on the skin (7). We recommend using a vitamin C serum during the day and copper peptides as a part of your nighttime routine.
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Peptides are beneficial for a wide range of skin types, from oily to dry skin. They can be used by anyone looking to prevent signs of skin aging, but peptides can also help mature skin with visible fine lines and wrinkles. Moreover, few peptides have presented evidence supporting their use on sensitive skin (8). If your skin is reactive and sensitive, it’s always a good idea to do a test patch first.
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Peptides are generally considered to be safe. Peptide products are usually well tolerated by the skin, as they are not known to cause irritation similar to what other active ingredients can. However, peptides should be used with caution in people with very sensitive skin.
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Generally, peptides are highly active at very small concentrations levels. Copper peptides in particular, are effective from 0.03%.
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Not all peptides used in skincare have been studied and compared to Vitamin C (ascorbic acid) and vitamin A (retinoic acid and retinol). However, there is a study with 20 women that showed that copper peptides increased the production of new collagen in 70% of the people treated, obtaining a superior result when compared to ascorbic acid (50%) or retinoic acid (40%) (2).
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Peptides have long names because they are made up of 2 to 50 amino acids. The name of a peptide is determined by the length of its amino acid chain and the molecules attached to it. For instance, copper tripeptide (Cu-GHK) consists of a mineral ion combined with three amino acids (tri meaning three). On the other hand, palmitoyl pentapeptide-4 (Matrixyl®) is composed of a fatty acid joined with five amino acids (penta indicating five).
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Skin proteins such as collagen and elastin are the most important structural component of the skin. They play a key role in maintaining skin health by providing strength, hydration, and elasticity.
However, as you age, your body begins to produce less collagen and your skin becomes thinner, drier, and less elastic. The logic would be to use cosmetics with collagen and elastin as a way to prevent the signs of skin aging. But, it doesn’t quite work like that.
Proteins are molecules too large to be absorbed by the skin, thus any cosmetic with proteins (collagen or elastin) acts only as a moisturizer, but they won’t have any effect on collagen production. Since peptides are much smaller molecules capable, they are able to actually penetrate the skin when applied topically and promote collagen.
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1. Lima, T. N. & Aparecida, C. Bioactive Peptides : Applications and Relevance for Cosmeceuticals. Cosmetics 5, (2018).
2. Schagen, S. K. Topical peptide treatments with effective anti-aging results. Cosmetics 4, (2017).
3. Errante, F., Ledwoń, P., Latajka, R., Rovero, P. & Papini, A. M. Cosmeceutical Peptides in the Framework of Sustainable Wellness Economy. Front. Chem. 8, 1–8 (2020).
4. Wang, Y. et al. The anti-wrinkle efficacy of argireline, a synthetic hexapeptide, in chinese subjects: A randomized, placebo-controlled study. Am. J. Clin. Dermatol. 14, 147–153 (2013).
5. Hostynek, J. J., Dreher, F. & Maibach, H. I. Human skin retention and penetration of a copper tripeptide in vitro as function of skin layer towards anti-inflammatory therapy. Inflamm. Res. 59, 983–988 (2010).
6. Escobar, S., Valois, A., Nielsen, M., Closs, B. & Kerob, D. Effectiveness of a formulation containing peptides and vitamin C in treating signs of facial ageing: three clinical studies. Int. J. Cosmet. Sci. 43, 131–135 (2021).
7. Shen, J. et al. Ascorbate oxidation by iron, copper and reactive oxygen species: review, model development, and derivation of key rate constants. Sci. Rep. 11, 1–14 (2021).
8. Resende, D. I. S. P., Ferreira, M. S., Sousa-Lobo, J. M., Sousa, E. & Almeida, I. F. Usage of synthetic peptides in cosmetics for sensitive skin. Pharmaceuticals 14, 1–22 (2021).