Palmitoyl Dipeptide-6 (Diffuporine): skin-firming cosmetic peptide
A lab-made cosmetic ingredient added to anti-aging creams to help support skin firmness and barrier function; used only in cosmetics, not an approved drug.
A researcher, an agent, or an algorithm wrote down the sequence and picked a target to hit.
An AI model like OpenFold3 or AlphaFold built a 3D structure and scored how well it fits the binding site.
A second contributor repeated the computation on their own hardware and the scores matched.
A chemistry service or a researcher ordered the sequence, it was manufactured, and mass spectrometry confirmed the right molecule was produced.
A binding or activity measurement confirmed that it actually does what the computer predicted — or didn't.
Snapshot
Class: Cosmetic lipopeptide / palmitoyl peptide family
Evidence tier: In vitro / assay evidence
Status: Cosmetic ingredient; no approved therapeutic status
Best-supported effect: Fibroblast and extracellular-matrix signaling proposed in cell-culture systems; category-level mechanistic rationale for skin barrier penetration (in vitro / mechanistic)
Main caveat: No independent published human RCT for isolated Palmitoyl Dipeptide-6; "retinol-like" framing is marketing language, not pharmacological equivalence
What this is
Palmitoyl Dipeptide-6 is a two-amino-acid cosmetic peptide (most commonly reported as valine-tryptophan, Pal-VW) covalently conjugated at the N-terminus to palmitic acid (C16 saturated fatty acid). The lipid attachment is the defining structural feature shared across the palmitoyl peptide family — it converts an otherwise hydrophilic short peptide into an amphipathic molecule that partitions more readily into the lipid-rich stratum corneum than the unmodified peptide would. It is used as a topical ingredient in anti-aging serums and creams and is often marketed as a "retinol alternative" for fine-line reduction and skin smoothing. That framing is marketing shorthand: Palmitoyl Dipeptide-6 does not bind retinoic acid receptors and does not share the pharmacology of retinoids, which have decades of controlled dermatologic evidence for photoaging. The proposed pathway is fibroblast and extracellular-matrix signaling — a different biological route toward similar appearance-related endpoints.
Evidence map
| Evidence layer | Grade | What it supports |
|---|---|---|
| Human | None identified | No independent published human RCT for isolated Palmitoyl Dipeptide-6 identified in available literature; available in vivo data is supplier- or formulation-associated and includes the peptide as one of multiple actives |
| Animal | None identified | Dedicated animal or ex vivo skin studies of Palmitoyl Dipeptide-6 in isolation are sparse in available literature; most supporting evidence is extrapolated from the broader palmitoyl peptide and matrikine category |
| In vitro | Weak | Cell-culture evidence for fibroblast signaling and extracellular-matrix protein effects (collagen, fibronectin, glycosaminoglycans) is described for the broader palmitoyl peptide and matrikine category; dedicated in vitro data for this specific dipeptide in isolation is limited in available literature |
| Computational | None identified | No computational or docking data identified |
| Mechanism | Plausible | Palmitoyl-delivery strategy for stratum-corneum penetration is well-characterized across the peptide family; fibroblast matrikine signaling is an established mechanism in cosmetic peptide biology; the gap is between category-level rationale and dedicated evidence for this specific dipeptide |
Claim check
| Claim | Verdict | Evidence layer | Confidence |
|---|---|---|---|
| Fine-line and wrinkle-depth reduction via topical application | Weak / not independently established for this peptide | In vitro / category | Low — no independent RCT for isolated compound |
| Skin firmness and smoothing improvement | Weak / not independently established for this peptide | In vitro / category | Low — supplier- and formulation-associated data only |
| Equivalent efficacy to topical retinoids ("retinol-like") | Contradicted / not supported | None | High — no shared pharmacology; no head-to-head clinical trial |
| Fibroblast and ECM signaling activity | Supported (in vitro, category level) | In vitro | Medium — category-level rationale is credible; dedicated data for isolated dipeptide is limited |
| Safe for topical cosmetic use | Weak / limited data | In vitro / anecdotal | Low — generally well-tolerated in cosmetic use reported; no dedicated safety trial identified in source |
Assay conditions
This section reports conditions described in available literature for the palmitoyl peptide / matrikine category. It does not establish human dosing or in vivo exposure.
| Context | System | Assay condition | Timepoint | Endpoint | Limitation |
|---|---|---|---|---|---|
| In vitro cell culture (category-level) | Fibroblast cultures | Short peptide conjugated to palmitic acid; exact concentrations for isolated Palmitoyl Dipeptide-6 not individually extracted in source | Not individually extracted | Extracellular-matrix protein expression (collagen, fibronectin, glycosaminoglycans); fibroblast contractility and morphology | Data is category-level (palmitoyl peptide family); dedicated assay data for isolated Palmitoyl Dipeptide-6 not separately extracted in this card |
| Cosmetic formulation in vivo (supplier-associated) | Human skin, in formulation with multiple actives | Topical application; exact regimen not individually extracted in source | Not individually extracted | Appearance-related endpoints (fine-line, smoothness); not standardized placebo-controlled | Peptide combined with other actives; no isolated efficacy extractable; supplier-associated |
Assay limitations
- All four references identified are review articles; no primary in vitro or clinical trial for isolated Palmitoyl Dipeptide-6 was individually extracted from available literature.
- Mechanistic rationale for fibroblast and ECM signaling is extrapolated from the broader palmitoyl peptide and matrikine category, not from dedicated studies of this specific dipeptide in isolation.
- Skin penetration is the rate-limiting step for cosmetic peptides; the actual fraction of applied peptide reaching viable epidermis (where fibroblasts reside) is not characterized in available literature for this compound.
- Supplier-associated formulation studies combine multiple actives, making isolated contribution of Palmitoyl Dipeptide-6 to observed outcomes unassessable from available data.
- In vitro activity in cell culture does not establish in vivo skin efficacy or systemic tolerability.
Regulatory status
No approved therapeutic status identified. Palmitoyl Dipeptide-6 is regulated as a cosmetic ingredient, not as a drug, and has no FDA or equivalent major regulatory approval for any medical indication.
| Region / body | Status | Notes |
|---|---|---|
| US (FDA) | Cosmetic ingredient | No drug approval; regulated under cosmetic rules; no approved indication |
| EU | Cosmetic ingredient | Expected to be governed by EU Cosmetics Regulation; independent verification not performed in this card |
| WADA | Not checked | No information in source; not expected to be performance-relevant |
| Prescription / OTC drug | Not applicable | Not a drug in any jurisdiction identified in source |
Mechanism
Palmitoyl Dipeptide-6 is a lipopeptide with a two-amino-acid core (valine-tryptophan) covalently linked at the N-terminus to palmitic acid. The palmitoyl group converts the hydrophilic dipeptide into an amphipathic molecule that partitions into the lipid-rich stratum corneum more readily than the bare peptide, facilitating delivery toward viable epidermis — though only a modest fraction of applied peptide is expected to reach viable epidermis in typical cosmetic vehicles.
The proposed biological activity is at the level of fibroblast signaling and extracellular-matrix remodeling, consistent with a matrikine-style mechanism: short peptide fragments or peptide-containing signals that interact with fibroblasts to modulate expression of structural proteins such as collagens, fibronectin, and glycosaminoglycans. This mechanism class is established for cosmetic peptides more broadly; the specific receptor or primary target protein mediating Palmitoyl Dipeptide-6's activity is not well characterized in the independent peer-reviewed literature, and published research extrapolates the rationale from the broader palmitoyl peptide family rather than from dedicated studies of this dipeptide in isolation.
The "retinol-like" positioning refers to a similar appearance endpoint (fine-line reduction, skin smoothing) and does not reflect shared pharmacology. Retinoids act through nuclear retinoic acid receptors with global epidermal effects. Palmitoyl Dipeptide-6 does not engage that pathway.
Target confidence: Inferred / category-level extrapolation — not directly characterized for this specific dipeptide in available literature.
Chemistry
| Field | Value |
|---|---|
| Common name | Palmitoyl Dipeptide-6 |
| INCI / marketing name | Palmitoyl Dipeptide-6; also known as Palmitoyl Val-Trp, Pal-VW, Palmitoyl Dipeptide-6 Diaminobutyroyl Hydroxythreonine (per source aliases) |
| Amino-acid core | Val-Trp (valine-tryptophan; most commonly reported in published cosmetic literature) |
| Length | 2 amino acids |
| Topology | Lipidated |
| Modification | N-terminal palmitoyl group (palmitic acid, C16 saturated fatty acid) |
| Sequence confidence | Needs review — multiple alias names in source; Diaminobutyroyl Hydroxythreonine alias suggests possible variant or alternative form; source does not resolve |
| Molecular weight | Not individually extracted in source |
| Formula | Not individually extracted in source |
| CAS | Not individually extracted in source |
Sequence note: Published research lists multiple alias names for this compound including "Palmitoyl Val-Trp" (Pal-VW) and "Palmitoyl Dipeptide-6 Diaminobutyroyl Hydroxythreonine." These aliases may reflect different forms, formulation variants, or nomenclature inconsistency in the cosmetic ingredient literature. The sequence reported most consistently in available literature is Val-Trp. The alternative alias implies a different sequence; this discrepancy is noted but not resolved in available literature.
Open questions
- Dedicated in vitro characterization: No primary in vitro study of isolated Palmitoyl Dipeptide-6 (as distinct from the palmitoyl peptide category) at defined concentrations and specific endpoints was identified in available literature. Dedicated cell-culture data for this dipeptide in isolation would strengthen or qualify the category-level rationale.
- Human efficacy in controlled conditions: No independent human RCT with placebo control, isolated Palmitoyl Dipeptide-6, standardized endpoints, and adequate duration is identified in available literature. Whether category-level fibroblast signaling translates to measurable, reproducible skin outcomes in independent controlled trials remains unestablished.
- Skin-penetration profile: The fraction of applied peptide reaching viable epidermis and papillary dermis across commercial vehicle types is not characterized in available literature. Penetration efficiency is a key variable for cosmetic peptide efficacy.
- Sequence identity and nomenclature: Published research lists two structurally distinct alias names (Pal-VW and Palmitoyl Dipeptide-6 Diaminobutyroyl Hydroxythreonine), which may indicate nomenclature inconsistency or distinct forms. Clarifying the canonical sequence is needed for rigorous research comparison.
- Long-term effects: Sustained topical use data, any chronic safety signals, and optimal concentration for clinical effect are all absent from available literature.
Research directions for this peptide, selected from the current sources — hypotheses you can explore and model. None of it is proven yet; tap any one to see the full thinking.
Could the tryptophan piece of this peptide trigger the same cellular sensor that responds to UV-generated skin chemicals?
If so, this would explain why the peptide appears to reduce signs of aging, and could help scientists design better versions that dial in exactly how much of that response to trigger, without sun damage.
If the attached fat chain were shorter, would more of the peptide get past the outer skin barrier to reach the cells it is meant to affect?
If true, a simple chemistry change could make existing Pal-VW products more effective at lower concentrations, reducing cost and potential irritation for consumers.
Does this short peptide share the anti-inflammatory skin effect already shown for longer fatty-acid peptides in the same chemical family?
If true, a widely available cosmetic ingredient might offer real relief for sun-sensitive skin, and could be developed into affordable over-the-counter products for people prone to UV skin reactions.
▸3-letter notation
▸citationbibtex
@peptide{pep10963,
sequence = {VW},
target = {},
author = {peptidemodel},
year = {2026},
status = {designed}
}