Decapeptide-12 is an oligopeptide with proposed anti-tyrosinase activity, composed of twelve amino acids and exhibiting the sequence Try-Arg-Ser-Aar-Lysd-Tyr-Ser-Ser-Trp-Tyr. It is thought to function primarily to restrain Tyrosinase—the enzyme researchers believe is responsible for the excessive production of melanin, which may result in patchy pigmentation upon the epidermal layer’s surface.

Lipopeptide is a common name for Biopeptide EL, also known as palmitoyl hexapeptide-12. As the name suggests, this peptide is made of six amino acids and has a palmitic fatty acid addition. The inclusion of palmitic acid within the Lipopeptide structure is thought to enhance penetration to the deeper layers of various structures made of skin cells. The amino acids in the peptide are valine-glycine-valine-alanine-proline-glycine (VGVAPG), and the sequence is one of the most common found in naturally occurring proteins like elastin and its precursor, tropoelastin.

By mimicking fragments of elastin, the peptide is thought to interact with fibroblast cells and exert a potential impact on the production of vital proteins to the skin’s extracellular matrix (ECM). Fibroblasts are a subset of cells found in connective tissue, such as the one that provides support for skin cells. Fibroblasts can actively produce ECM proteins, and some of the most important proteins are considered to be collagen, elastin, and hyaluronic acid. According to scientific research, Lipopeptide may potentially enhance the creation and growth of collagen and hyaluronic acid within the ECM.

Syn-Coll, otherwise known as Palmitoyl Tripeptide-5 or Tripeptide-5, is a synthetic peptide that was developed to enhance the production of type I collagen. It appears to repair damages caused by photo-aging, and Syn-Coll has also been suggested to support the regeneration of skin protein production, such as elastin or collagen. Syn-Coll (Palmitoyl Tripeptide-5) is the synthetic equivalent of Thrombospondin 1 (TSP-1). TSP-1 is an extracellular matrix protein and is found in the skin near collagen and elastin. Syn-Coll appears to mimic the functions of TSP-1, possibly aiding in the prevention of collagen degeneration via stimulating the release of TGF- induced by TSP-1.^[1] TGF-β is an essential growth factor potentially significant in preserving skin integrity and facilitating the development of skin structures, mainly through the promotion of collagen synthesis. Additionally, Syn-Coll, a synthetic peptide, has been the subject of extensive research in animal models and laboratory experiments. The findings tentatively indicate that Syn-Coll might enhance collagen production and potentially inhibit its degradation. The inhibition of collagen breakdown by Syn-Coll is possibly due to its ability to suppress the activity of matrix metalloproteinases (MMPs), including MMP1 and MMP3, which are enzymes studied for their role in the degradation of collagen in the skin. The peptide is palmitoylated, to potentially extend its bioavailability in experiments involving different skin tissue models.

Nonapeptide-1, also termed Melanostatine-5, is a peptide that may prevent the activation of pigment-producing cells in the skin called melanocytes. It appears to be one of the most potent inhibitors of a receptor found in these pigment-producing cells, called the melanocortin-1 receptor (MC1R). Researchers have explored a peptide library containing 31,360 structurally different compounds, and it appears that the most potent inhibitor identified was Met-Pro-D-Phe-Arg-D-Trp-Phe-Lys-Pro-Val-NH₂, aka Nonapeptide-1.^[1] Structural analysis has revealed that specific amino acids, such as D-Trp at position 5 and Phe at position 6, are considered crucial for their antagonistic potential. The presence of D-Phe at position 3 further underscores such potential. Research on animal models suggests that Nonapeptide-1 may inhibit the synthesis of melanin, bringing it to the forefront of research on conditions impacting skin pigmentation, such as melasma. Studies in animal models posit that Nonapeptide-1 may reduce the synthesis of melanin and potentially decrease pigmentation on a considerable scale.

Acetyl Hexapeptide-3 (Argireline) is a peptide chain of amino acids with the following sequence: Ac-Glu-Glu-Met-Gln-Arg-Arg-NH2. It is a fragment of the SNAP-25 (synaptosome-associated protein 25 kDa).^[1] SNAP-25 is a key component of the SNARE (Soluble N-ethylmaleimide-sensitive factor Attachment protein Receptor)-Synaptotagmin-1 complex. This is a protein assembly that facilitates the release of neurotransmitters, such as acetylcholine, into the synaptic cleft between nerve cells and muscle cells. SNAP-25 is considered to be critical in this process because it appears to be in the assembly of the SNARE complex. This may also lead to the release of acetylcholine, thus triggering muscle contraction. Acetyl Hexapeptide-3 resembles the SNAP-25 protein, particularly the portion that is believed essential for SNARE complex formation.

By inhibiting its formation, the peptide may also prevent neurotransmitter release and muscle contraction. Researchers have investigated Acetyl Hexapeptide-3 (Argireline) for its potential to support skin cell structure and reduce wrinkling along the stratum corneum. Continuous muscle movements result in wrinkling, and the devitalization of muscle contractions may possibly inhibit the development of new lines and decrease the depth of existing skin tissue creases and wrinkles. Acetyl Hexapeptide-3 (Argireline) may prevent muscles from moving or contracting. Researchers also posit that the peptide may support endogenous collagen production to preserve the skin’s extracellular matrix.

Syn-AKE is a peptide, also known as tripeptide-3 or dipeptide diaminobutyroyl benzyl amide diacetate. Syn-AKE, a synthetic peptide ingredient, appears to mimic the actions of the Waglerin-1 peptide, which is 21 amino acids in length. Waglerin-1 functions primarily as a muscle relaxant by inhibiting the activity of acetylcholine at the neuromuscular junction, which may potentially result in reduced muscle contractions. Acetylcholine is a neurotransmitter considered essential for muscle movement, and its inhibition at the neuromuscular junction prevents the normal contraction signals from reaching muscles. In the development of Syn-AKE, researchers sought to synthesize a peptide that might potentially mimic this action. Thus, the peptide Syn-AKE was engineered to emulate the mechanism by which Waglerin-1 acts, but in a more selective manner. Researchers suggest Syn-AKE may act to reduce transmission between muscles and nerves, working similarly to botulinum toxin to relax muscles and thus reduce instances of creasing and wrinkle development along epidermal surfaces, as suggested in animal model research. The apparent reduction of this transmission appears to be reversible when triggered by Syn-AKE. Therefore its action is temporary.^[1] According to Pentapharm, “the Syn-AKE invokes its action by blocking the muscle nAChR in a reversible manner by blocking the ion channel. As a result, the Na+ uptake is substantially disturbed, and the muscles remain relaxed.”

Tripeptide-29 is a peptide that is one of the basic monomers of collagen. Collagen is a long-chain polymer composed of short monomers made of three consecutive amino acids. These monomers combine to form a secondary structure, which then may form tertiary and even quaternary structures. These complex structures may have many potential emergent properties. For example, most collagen molecules are thought to play roles in providing structural integrity and elasticity to the cellular complexes in tissues like the stratum corneum, tendons, and bones.

Collagen subunits most often follow the pattern of Gly-Pro-X, Gly-Xo-X, or Gly-X-Hyp. Tripeptide-29 is a GlyPro Hyp peptide, a complete synthetic analog of common collagen building blocks. Beyond its proposed involvement in collagen synthesis, researchers speculate that Tripeptide-29 may have additional biological implications. For instance, some preliminary studies suggest it may act as an antioxidant, potentially aiding in the protection of cells against oxidative stress, which is the imbalance between free radicals and antioxidants that may lead to cellular damage.

It is hypothesized that Tripeptide-29 might exhibit anti-inflammatory properties, possibly reducing inflammation; anti-fibrotic actions, which may help mitigate excessive formation of fibrous connective tissue; and anti-melanogenic characteristics, potentially influencing melanin production and affecting pigmentation processes in the dermal and epidermal layer.

GHK-Cu (Copper Tripeptide) is a tripeptide that scientists assert is naturally present in blood plasma. It has a sequence of Gly-His-Lys (glycine, histidine, and lysine,) which readily binds with copper to form the copper tripeptide. Scientific studies carried out in different research laboratories worldwide have explored its various biological roles. GHK-Cu exhibits some potential to influence various biological pathways, including an apparent induction of tissue repair, attraction of immune cells, antioxidant and anti-inflammatory characteristics, activation of collagen and glycosaminoglycan synthesis in skin fibroblasts, regulation of extracellular matrix components like decorin, and possible promotion of blood vessel growth. Recent studies indicate its potential role in stem cell biology and anti-tumor research as well.

Pal-AHK, also referred to as Palmitoyl Tripeptide-3, is a tripeptide with a fatty acid attachment. It consists of amino acid sequences (alanine-histidine-lysine) and appears to be attached to a Palmitoyl fatty acid molecule. The fatty-acid component of AHK makes it lipophilic (soluble in fat), which may increase the potential of the peptide for penetration and absorption by epidermal cells in experimental models while maintaining the same mechanisms of action as regular AHK. AHK appears to be a multifunctional copper-binding peptide that has been studied for its potential role in supporting cellular functions related to the kin’s extracellular matrix.

Research indicates that AHK-Cu may increase the proliferation and viability of dermal fibroblasts—the primary cells responsible for producing collagen and other essential proteins in the extracellular matrix (ECM).^[1] Moreover, the peptide appears to possess significant antioxidative potential compared to other tripeptides when investigated via chromatographic evaluations. This appears to be related to its potent metal-chelating properties.