Peptides remain a buzz word in the world of anti-aging skin care due to their performance and their ability to be used by all skin types without causing irritation or sensitivity. It is likely that your clients have either heard of them, currently use peptide-based skin care or are interested in finding the right peptide-focused product. They continue to evolve and have developed a cult following along the way based on their results. It’s important to know where peptides originated and how they develop.
Peptides are proteins
Peptides are tiny protein fragments—think of them as a series of amino acids that improve cell communication—but the correlation of how important the composition of a peptide is to the body and skin is not always made. How exactly do protein fragments or amino acid chains improve the look and health of skin? In order to understand this, the significance proteins have within the body and skin must be realized.
Within the skin, collagen is made of protein, which is comprised of amino acids. In fact, collagen makes up for 25–35% of the whole body’s protein content,1 and this percentage is divided between at least 24 different types of collagen that contribute to everything from structural concerns, such as anchoring the skin together, to the appearance of skin’s elasticity on the surface. Awareness of the decline of collagen as a person ages, and the need to maintain healthy and ample collagen to minimize the appearance of fine lines and wrinkles is increasing. Many are unaware that other protein-based structures, including laminin and elastin, contribute to skin’s strength and to an overall youthful appearance, but also decline with age, similar to collagen. The role protein plays in the body is an essential one.
Aside from water, protein is the most abundant molecule in the body. Proteins do more than strengthen the body; they are essential to every organism and are required for nearly every process within cells. Hormones rely on proteins to transmit messages throughout the body. Proteins affect a person’s thoughts and emotions by supporting both neurotransmitters in the brain and enzymes that catalyze chemical reactions. They balance fluids and electrolytes, and assist in the regulation of the acid-base balance. They also serve as transportation vehicles for nutrients. An understanding of the role of proteins in the body serves as a foundation for comprehending the function of peptides. The role proteins play within the body correlates with the actions of four categories of peptides, including signal peptides, enzyme inhibitor peptides, neurotransmitter inhibitor peptides (otherwise known as neuropeptides) and carrier peptides.
Peptides already exist naturally within the body. Protein is ingested through the diet, not only from meat, but also from a variety of plant sources, allowing people to obtain essential amino acids. These amino acids combine in specific sequences that result in peptides that perform a variety of critical functions. One of those functions is the process of creating collagen. A polypeptide undergoes a series of three processing reactions to eventually form a collagen molecule. Each collagen molecule is made up of 1,050 amino acids and creates a triple helix, where three protein chains are twisted together in a specific shape to form a sturdy, stable protein strand. These different strands of collagen then form a network with the body and skin, giving it its structure. By supplementing the skin from the outside with topically applied peptides, the outward reflection of supporting these natural processes is skin that looks and acts younger.
Topical peptides made their debut as skin care ingredients with the copper peptide, a carrier peptide known for delivering the wound-healing benefits of copper deeper within the skin, and palmitoyl pentapeptide-3, a signal peptide that was first offered as a retinol alternative for its outstanding performance and applicable use for all skin types, even sensitive skin. This first-generation peptide was shown to reactivate the signal for collagen I and IV, which restored skin thickness.2
While these first-generation topical peptides intrigued the skin care industry, second- and third-generation peptides are captivating the industry once again with their ability to address a broad range of aging concerns. One of these areas is the dermal epidermal junction (DEJ). The DEJ holds the skin together, improving its compactness, firmness and elasticity. It maintains skin cohesion and anchors the epidermis to the dermis. Imagine the skin as plates held together by a series of chain links. If one of these links becomes weak and breaks, the plates will slip. As the protein-composed links, such as laminin and integrin, become weak within the DEJ, the skin begins to sag, and loses elasticity and resilience.
Signal peptides. Syn-Tacks from Pentapharm, based on palmitoyl dipeptide-5, is a dual peptide that reinforces multiple proteins within the skin, including laminin and integrin, while strengthening collagen IV, VII and XVII. By reinforcing and anchoring the skin together, this signaling peptide lays a foundation for firmer, thicker, more elastic skin. Signal peptides behave as dispatchers, signaling cells to carry out specific functions, such as collagen support, just like proteins are required by hormones to transmit messages throughout the body. These messages can either be for an increased action or decreased action, which overlaps with the enzyme-inhibitor peptide category. This category works to either inhibit protein-degrading enzymes, or initiate responses to repair damaged or weakened tissues. Proteins support neurotransmitters in the brain and peptides help support processes in the skin by inhibiting communication within neurons. Peptides strengthen and nourish the skin in the same way that protein nourishes and strengthens the body. They enhance the delivery of nutrients by acting as transportation vehicles, and sources of strength and support to the skin.
Perfection Peptide P3 by Mibelle AG Biochemistry, or hexanoyl dipeptide-3 norleucine acetate, is another signal peptide that takes an age-defying approach closer to the role of enzymes or alpha hydroxy acids through exfoliation. As a person ages, cell turnover slows, leading to an increased appearance of wrinkles, accompanied by a rougher texture and reduced hydration. Desquamation requires the degradation of connections between the corneocytes that are formed by cell-adhesion proteins. Hexanoyl dipeptide-3 norleucine acetate competes for the bond that holds skin cells together, loosening skin cells and presenting a gentle method of exfoliation, helping skin become smoother, brighter and more evenly hydrated.
Enzyme-inhibitor peptides. Enzyme-inhibitor peptides help reduce the effects of enzymes, such as matrix metalloproteinases (MMPs). MMPs are enzymes involved in the degradation of proteins, including collagen. Reducing their actions can be just as important as strengthening collagen. Trylagen from Lipotec, based on tripeptide-10, citrulline and tripeptide-1, is a dual peptide combined with two hydrolyzed proteins that helps reduce enzymatic destruction caused by MMPs. Trylagen combats skin aging in three ways: by boosting collagen I, III and IV; by reducing the rate of collagen degradation; and by organizing this complex network.
Neuropeptides. The neuropeptide category has become very exciting over the years for its ability to reduce the appearance of expression lines. The primary mode of action for a neuropeptide is through the inhibition of acetylcholine. Acetylcholine is a transmitter released within the neuromuscular junction through a series of processes that eventually result in a muscle contraction. Acetyl hexapeptide-3 is a first-generation neuropeptide that blocks acetylcholine from its release. Syn-Ake from Pentapharm, or dipeptide diaminobutyroyl benzylamide diacetate, is a newer generation peptide that mimics the effects of waglerin 1, a 22-amino-acid-peptide string found within a temple viper’s venom. How this peptide differs from its predecessors is by its mode of action, as well as its swift performance. Syn-Ake doesn’t block acetylcholine from its release, but from its uptake by the receptors in the neuromuscular junction. Within the first two hours, the frequency of muscle contractions is reduced, which can lead to a visible reduction of wrinkles over time. The unique performance of both these neuropeptides in combination can lead to excellent anti-aging results.
Carrier peptides. Carrier peptides function to help stabilize and deliver important trace elements necessary for wound-healing and enzymatic processes. The most commonly encountered carrier peptide is used to stabilize and deliver copper into cells.3
Carrier peptides belong to a general category that acts as a facilitator of important substance transportation, but their major application is to deliver important trace elements, such as copper and manganese necessary for wound-healing and enzymatic processes. Recently, several peptides and proteins have been developed to accelerate and facilitate the delivery of bioactive molecules into the skin. These peptides and proteins are known as penetrating peptides, or membrane transduction peptides, and have basic transduction domains in their structure. A recent study demonstrated that short arginine-rich intracellular delivery peptides facilitate the transport of various proteins into living cells.4
The skin’s building blocks
Peptides are an amazing rejuvenating ingredient based upon the composition of the body and how it functions. They are the skin’s building blocks, contributing to its health, strength and structure. The benefits of peptides are already recognized within anti-aging skin care, and continue to evolve and progress. Educating clients on this breakthrough in anti-aging skin care will help them understand the science behind peptides.
- www.rcsb.org/pdb/static.do?p=general_information/news_publications/newsletters/2000q2/molecules.html (Accessed Sep 13, 2012)
- Z Draelos, From Proteins to Peptides—What They Mean to the Dermatologist, European Dermatology Review 31–32 (2006)
- M Lupo and A Cole, Cosmeceutical Peptides Dermatologic Therapy 20 343–349 (2007)
- F Gorouchi and HI Malbach, Role of Topical Peptides in Preventing or Treating Aged Skin, International Journal of Cosmetic Science 31 327–345 (2009)
April Zangl is CEO of HydroPeptide, and is a fitness and wellness management professional and skin ingredient expert. Her years of experience in the pharmaceutical and nutritional supplement industries have resulted in a deep understanding of how the body and skin works. She takes pride in making information on the latest beauty industry advancements accessible.