Cosmetic Peptides (Beauty Peptides): Introduction and Functions of Various “Peptides”

Cosmetic Peptides (Beauty Peptides): Introduction and Functions of Various “Peptides”

Introduction to Peptides

Peptides, also known as “peptides” in Chinese, are small molecules derived from the degradation of collagen, containing Amino Acid groups and classified as raw material products. Peptides are naturally occurring components in the human body, forming chain structures of amino acids. The proteins we are familiar with are essentially polypeptide chains. Peptides are composed of amino acids linked by peptide bonds, and each peptide can consist of various amino acids. Peptides composed of two amino acids are called dipeptides, those with three amino acids are tripeptides, and so on. Commonly mentioned peptides like tripeptides, pentapeptides, and even nonapeptides belong to oligopeptide chains. Each oligopeptide chain has different effects. Generally, peptides with fewer than 10 amino acids are called oligopeptides, those with more amino acids are called polypeptides, and those with more than 50 amino acids are called proteins. Due to the different types of amino acids they contain, dipeptides and tripeptides also come in various types, leading to the diverse functions and names of peptides we see today.

Peptides are involved in hormones, nerves, cell growth, and reproduction in the human body. Their importance lies in regulating the physiological functions of various systems and cells, activating relevant enzyme systems, promoting the permeability of intermediate metabolic membranes, or producing specific physiological effects by controlling DNA transcription or influencing specific protein synthesis.

Cosmetic Functions of Peptides

The biological activity of peptides depends on their amino acid composition and sequence. Various physiological processes in the human body are regulated by specific amino acid sequences in peptides or proteins. Therefore, bioactive peptides have become a new direction and approach in cosmetic research and application, with increasingly specialized functions such as anti-aging, repair, antioxidant, anti-edema, promoting hair regeneration, inhibiting melanin production, breast enhancement, and weight loss. The skin is the body’s natural barrier against external environmental damage, providing some protection against external stimuli thanks to the dense stratum corneum. However, this also prevents the nutrients in cosmetics from penetrating the skin surface. Nutrients need to pass through the cell membranes of the stratum corneum to enter the dermis. Large molecules and lipid-soluble substances can only be absorbed in small amounts through pores and sweat glands. Therefore, most cosmetics we use remain on the skin surface, while bioactive beauty peptides can more easily penetrate the gaps in the stratum corneum to reach the dermis and exert their effects. Initially, peptides were directly used in products by some European and American cosmeceuticals. Their mechanism of action is similar to that of proteins, promoting the proliferation of collagen, elastic fibers, and hyaluronic acid, increasing skin hydration, thickness, and reducing fine lines. Due to the different types of amino acids they contain, peptides can perform various functions to meet different skin needs.

Functions of Various Peptides

1.Dipeptides: Anti-Wrinkle: Locally block nerve signals that cause muscle contraction, affecting nerve transmission in the skin, relaxing facial muscles, and smoothing dynamic, static, and fine lines.

2.Tripeptides: Regeneration Tripeptides were the first peptide arrangement discovered and are considered growth factors that can stimulate the production of glycosaminoglycans and collagen. They were isolated from wound healing tissues in 1990 and have the effect of promoting wound healing and proliferation.

3.Tetrapeptides: Anti-Edema Tetrapeptides have anti-edema properties, improve microcirculation, and enhance blood circulation.

4.Pentapeptides: Firming (Palmitoyl Pentapeptide-3 = Palmitoyl-KTTKS, also known as Matrixyl) Pentapeptides were first used by dermatologists along with anti-aging ingredients like vitamin A, claiming to act directly on the dermis to promote collagen production and achieve skin firming. When combined with other moisturizing ingredients, they can accelerate the tightening and lifting effects.

5.Oligopeptides: Elasticity Oligopeptides promote the proliferation of collagen and hyaluronic acid, increasing skin hydration and elasticity.

6.Hexapeptides: Anti-Wrinkle Also known as botulinum toxin-like peptides, hexapeptides inhibit the excessive release of neurotransmitters and affect the transmission proteins between subcutaneous nerves and muscles. They are most effective in reducing dynamic wrinkles such as crow’s feet and nasolabial folds. French dermatologists have found that hexapeptides are particularly effective for wrinkles around the eyes.

7.Nonapeptide: Whitening When the skin is exposed to external stimuli or ultraviolet radiation, the α-melanocyte-stimulating hormone (α-MSH) in the basal layer cells binds to receptors on melanocytes, directly stimulating them and activating tyrosinase, which starts the production of melanin. Nonapeptide can block the formation of melanin at its source by interrupting the transmission of α-MSH signals, preventing it from binding to receptors on melanocytes, thereby reducing the chance of melanin production.

8.Copper Peptide: Revitalizing Copper peptide is a perfect combination of divalent copper ions and tripeptide. Initially, it was used as an oral medication for treating gastric ulcers. Copper is one of the essential elements in the body and plays a role in skin tissue by aiding wound healing. Copper ions cannot penetrate the deeper layers of the skin on their own. Therefore, through the combination of glycine, lysine, and histidine with a copper ion, copper peptide can deliver copper into the skin, effectively revitalizing it. Copper peptide can promote the production of collagen and elastin, and has antioxidant properties. It penetrates deeper into the skin, enhancing its self-repair ability and achieving the ultimate wrinkle-smoothing effect.