Skip to content
PeptideAI
In vitro onlyskin

Syn-Coll

A thrombospondin-1 mimic that converts latent TGF-beta into its active form, driving collagen synthesis through the body's own wound-repair switch.

Also known as Palmitoyl Tripeptide-5, Pal-Lys-Val-Lys, thrombospondin-1 mimetic peptide, SYN-COLL

In vitro only — Cell or tissue studies. A mechanism, not yet an effect in a living body.

The TGF-beta activation mechanism has good in-vitro support. Human efficacy is supplier panel data only, and the frequently cited '350% collagen increase' is a cell-culture figure, not a skin measurement.

How it works

TGF-beta is secreted as a latent complex and must be unmasked before it can bind its receptor. Thrombospondin-1 does this physiologically via a KRFK sequence that displaces the latency-associated peptide. Palmitoyl tripeptide-5 presents a Lys-Val-Lys motif designed to reproduce that activation step, so it recruits the skin's existing latent TGF-beta pool rather than adding an exogenous growth-factor signal. The palmitoyl chain provides the lipophilicity needed for stratum corneum partitioning. Because TGF-beta drives fibrosis as well as repair, the same mechanism that builds collagen is the reason this class is best kept at cosmetic concentrations.

Targets: Thrombospondin-1 pathway, Latent TGF-beta activation, Collagen I synthesis

Dosing

ProtocolDoseFrequencyRoute
Standard leave-on serumNo timing constraints.—once or twice dailytopical
  • · Trade solution used at 1-3% of the formula. From raw powder, 0.01-0.05% w/w is the usual target.

Cycling

Continuous daily use.

Work out your exact syringe units →

Pharmacology

Half-life
Not established.
Onset
8-12 weeks for visible firmness changes.
Routes
topical
Molecule
Palmitoylated tripeptide (lipopeptide)
Sequence length
3 amino acids
Molecular weight
611.9 Da

Handling

Diluent
Glycol or ethanol wetting step, then water or serum base
Typical mix
10 or 50 mL
Vial sizes
50, 100, 200 mg
Lyophilised
Sealed, cool and dry; freezer for long-term.
Reconstituted
Refrigerated in a preserved base.

Mixing

Palmitoylated and poorly water-wettable; do not try to dissolve it directly in plain water.

Side effects

  • rareIrritation

Do not use if

  • Active keloid or hypertrophic scarring tendency — TGF-beta activation is the wrong signal to amplify in fibrosis-prone skin.

Combining it

  • synergymatrixyl — Two independent routes to fibroblast collagen output.
  • synergyghk-cu-topical — Commonly layered in firming formulas.

What to monitor

  • · Standardised photography; watch scar-prone areas for any thickening.

Legal status

Cosmetic ingredient (INCI Palmitoyl Tripeptide-5) approved worldwide.

References

  • DSM SYN-COLL technical dossier (other)
  • Schultz-Cherry et al., thrombospondin-1 activation of latent TGF-beta (preclinical)

Mechanism in depth

This is the only peptide in the cosmetic category whose mechanism recruits an existing reservoir rather than adding a new signal, and that is genuinely clever. TGF-beta is secreted as a small latent complex: the mature cytokine is non-covalently wrapped in its own latency-associated peptide, which sterically blocks receptor binding. Skin contains a substantial pool of this latent TGF-beta sitting in the matrix doing nothing. Thrombospondin-1 activates it physiologically, and Ribeiro and colleagues at Alabama mapped exactly how: a KRFK sequence in the type 1 repeats of thrombospondin-1 interacts with the LSKL sequence of the latency-associated peptide, and that interaction induces a conformational change that releases active TGF-beta without any proteolysis. It is a clean, well-characterised, receptor-free activation mechanism. Palmitoyl tripeptide-5 presents a Lys-Val-Lys motif intended to reproduce that step. If it works, you get TGF-beta receptor signalling — SMAD2/3 phosphorylation, SMAD4 complex formation, nuclear translocation and transcription of COL1A1, COL1A2, fibronectin and PAI-1 — from the skin's own latent stores, at whatever concentration that pool supports. Now the caution, which is not decorative. TGF-beta is the master fibrotic cytokine. It is the pathway that drives keloids, hypertrophic scars, scleroderma and organ fibrosis. Using a topical cosmetic to deliberately unmask it is a defensible trade at low concentrations on normal skin and a bad one in anyone with a fibrotic tendency. The Core record's keloid contraindication is the single most mechanistically justified contraindication in this entire class.

What usually goes wrong

The frequently quoted 350% collagen increase is a cell-culture number, not a skin measurement, and it gets repeated as though a face gained 350% collagen. Treat it as evidence the mechanism does something in a dish. The real risk, which is small but not zero, is in fibrosis-prone skin: darker Fitzpatrick types with a keloid history, anyone with active hypertrophic scarring, anyone on a post-surgical scar. TGF-beta activation is the wrong signal there. Watch treated scar-prone areas for thickening rather than assuming a cosmetic peptide cannot do that. Otherwise the usual concentration confusion applies: supplier level is 1-3% of a dilute trade solution, which is roughly 0.01-0.05% actual peptide.

Pharmacokinetics

Crosses blood-brain barrier
no
Metabolism
Esterase cleavage of the palmitoyl bond releases the free Lys-Val-Lys tripeptide, which peptidases then degrade.
Elimination
No meaningful systemic exposure.

Receptor targets

  • Latency-associated peptide of the small latent TGF-beta complex — The parent thrombospondin-1 KRFK/LSKL interaction is characterised; no affinity published for the KVK cosmetic mimetic

    Conformational release of active TGF-beta without proteolysis.

  • TGF-beta receptor I/II — SMAD2/3 cascade (downstream) — Indirect; the peptide does not bind the receptor

    SMAD2/3 phosphorylation drives COL1A1 and COL1A2 transcription. Also drives PAI-1 and the fibrotic programme, which is the double edge.

What to expect, and when

Week 8-12: firmness changes if they occur. TGF-beta-driven collagen deposition is genuinely slow — the transcriptional response is fast but matrix accumulation and cross-linking take months. Week 16-24 is the honest assessment point.

Stacking and comparisons

No chemical incompatibilities. Commonly layered with Matrixyl or GHK-Cu in firming formulas, and that combination is defensible because the routes to collagen output are independent — matrikine signalling, copper-dependent enzyme support and TGF-beta activation are three different things. The combination to think twice about is Syn-Coll with anything else that pushes TGF-beta, including growth-factor serums and aggressive post-procedure protocols in someone who scars badly. And if you are using it after microneedling or laser, remember that the wound response is already a TGF-beta surge; adding more is not obviously helpful and in a keloid-former is actively unwise.

Mechanistically the most interesting collagen peptide in the class and clinically the least supported. Against Matrixyl, Syn-Coll has the better-characterised upstream mechanism and no human trial; Matrixyl has the trial. Against GHK-Cu, GHK-Cu actually suppresses excessive TGF-beta-driven fibrosis while stimulating repair, which is close to the opposite regulatory stance — they are not simply additive, and in scar-prone skin GHK-Cu is the safer of the two. Against a retinoid, no contest.

Rough cost

$12–$65/month. Raw palmitoyl tripeptide-5 runs roughly $40-90 per gram at very low use levels. Finished products $15-65 a month. Market observation, not a sourced pricing study.

Genuinely uncertain

  • No published data confirm that the KVK motif actually activates latent TGF-beta the way the parent KRFK sequence does. The mechanism is asserted by analogy.
  • No independent human trial of palmitoyl tripeptide-5 exists.
  • The 350% collagen figure is cell culture and I could not resolve it to a primary indexed publication.
  • No permeation data exist for this peptide.
  • Whether cosmetic-level exposure produces enough TGF-beta activation to matter clinically, in either direction, is unknown.

Papers