Palmitoyl Pentapeptide-4 (Matrixyl)

Overview

Palmitoyl Pentapeptide-4, marketed under the trade name Matrixyl, is a synthetic lipopeptide developed and patented by the French cosmetic ingredient company Sederma (a subsidiary of Croda International). It was introduced to the cosmetics industry in the early 2000s and has since become one of the most commercially successful peptide actives in anti-aging skincare.

The peptide consists of a five-amino-acid sequence (KTTKS) conjugated to a palmitic acid (C16 fatty acid) chain at its N-terminus. The KTTKS sequence corresponds to a fragment of the procollagen I C-terminal propeptide, a naturally occurring matrikine — a class of extracellular matrix (ECM) fragments that signal cells to produce new matrix components. The palmitoyl modification enhances lipophilicity, improving the peptide's ability to penetrate the stratum corneum via transdermal delivery and reach the dermal fibroblasts where it exerts its biological effects.

Matrixyl gained widespread public attention when early clinical studies demonstrated measurable reductions in wrinkle depth and volume following topical application, positioning it as an accessible alternative to injectable anti-aging treatments. It remains one of the most extensively studied cosmetic peptides and is incorporated into formulations ranging from mass-market moisturizers to professional-grade serums.

Structure

Palmitoyl Pentapeptide-4 consists of the pentapeptide KTTKS linked to a palmitoyl (C16:0) lipid tail:

Sequence: Pal-Lys-Thr-Thr-Lys-Ser (Pal-KTTKS)

• Molecular formula: C₃₂H₅₈N₆O₉
• Molecular weight: 802.93 g/mol (palmitate salt form)
• CAS Number: 214047-00-4
• Origin: Synthetic; sequence derived from type I procollagen C-terminal propeptide
• INCI name: Palmitoyl Pentapeptide-4

The KTTKS fragment was identified by Katayama et al. (1993) as the minimal active sequence within the larger procollagen C-propeptide capable of stimulating collagen synthesis and ECM production in human dermal fibroblasts. The palmitoylation strategy was subsequently developed by Sederma to address the poor skin permeation characteristics of the unmodified hydrophilic pentapeptide.

The earlier designation "Palmitoyl Pentapeptide-3" was used in initial publications and has since been updated to Palmitoyl Pentapeptide-4 under revised INCI nomenclature. Both names refer to the same compound.

Mechanism of Action

Matrikine Signaling

The KTTKS sequence functions as a matrikine — a bioactive fragment of an ECM macromolecule that regulates cell behavior through feedback signaling. During normal tissue turnover, enzymatic degradation of type I collagen releases peptide fragments, including sequences encompassing KTTKS, which signal fibroblasts to upregulate new matrix synthesis. Matrixyl mimics this endogenous feedback loop.

Upon reaching dermal fibroblasts, Pal-KTTKS activates signaling cascades that upregulate the transcription of genes encoding key structural proteins:

• Collagen I and III — the primary structural collagens of the dermis
• Fibronectin — an ECM glycoprotein involved in cell adhesion and tissue architecture
• Elastin — responsible for skin elasticity and resilience
• Hyaluronic acid synthase — the enzyme producing hyaluronic acid, a critical dermal humectant

TGF-beta Pathway Involvement

Evidence suggests that KTTKS-mediated collagen stimulation involves activation of the transforming growth factor-beta (TGF-beta) signaling axis, a master regulator of ECM synthesis. TGF-beta activation leads to phosphorylation of Smad2/3 transcription factors, which translocate to the nucleus and drive expression of collagen and other matrix genes.

Lipid Tail and Skin Penetration

The palmitoyl chain serves a dual purpose. It increases the peptide's amphiphilicity, allowing it to integrate into the lipid bilayer of the stratum corneum and facilitate transdermal delivery. Additionally, the lipid tail may anchor the peptide within cell membranes at the site of action, prolonging its local residence time and enhancing fibroblast interaction.

Research Summary

Applications

Cosmetic Formulations

Matrixyl is one of the most widely formulated peptide actives in the cosmetics industry. Typical use concentrations range from 2–8% of the proprietary Matrixyl solution (which contains the peptide in a glycerin vehicle at a defined concentration). It is compatible with a broad range of formulation types including serums, creams, lotions, and eye treatments.

Key formulation considerations include pH stability (optimal range 5.0–6.5), compatibility with other actives (generally compatible with retinoids, vitamin C, niacinamide, and hyaluronic acid), and avoidance of strongly acidic conditions that may hydrolyze the peptide bond.

Matrixyl 3000 and Matrixyl Synthe'6

Sederma has introduced successive generations of Matrixyl-branded products:

• Matrixyl 3000 — a combination of Pal-KTTKS with Palmitoyl Tripeptide-1 (Pal-GHK), designed to provide synergistic ECM stimulation through two complementary matrikine pathways
• Matrixyl Synthe'6 — contains Palmitoyl Tripeptide-38, which stimulates synthesis of six major structural components of the dermal-epidermal junction

These branded combinations represent the evolution of the Matrixyl platform beyond the original single-peptide formulation.

Professional and Aesthetic Use

In professional aesthetics, Matrixyl-containing formulations are used as maintenance treatments between injectable procedures (botulinum toxin, dermal fillers) and as components of post-procedure recovery protocols to support collagen rebuilding.

Dosing Protocols

The following dosing information is compiled from published research and community discussion for educational purposes only. No FDA-approved human dosing guidelines exist for most research peptides. Always consult a qualified healthcare professional.

Matrixyl (Palmitoyl Pentapeptide-4 / Pal-KTTKS) is a topical cosmetic peptide.

Application notes: Apply to clean skin before heavier products. Most clinical studies evaluated 4-8 weeks of consistent use before measuring results. Often combined with Argireline (for dynamic wrinkles) and vitamin C (for antioxidant synergy). Compatible with most cosmetic ingredients. Stable across pH 4.0-7.0.

Related Compounds

• GHK-Cu — a naturally occurring copper tripeptide that stimulates collagen synthesis through distinct metalloenzyme-dependent mechanisms
• Palmitoyl Tripeptide-1 — a synthetic matrikine based on the GHK sequence; combined with Matrixyl in the Matrixyl 3000 blend
• Argireline — a cosmetic hexapeptide that reduces wrinkles through neuromuscular modulation rather than ECM stimulation
• Copper Peptides — a broader class of copper-binding peptides with ECM remodeling activity
• SYN-AKE — a snake venom-mimetic peptide with muscle-relaxant anti-wrinkle activity