Comparison
Matrixyl vs. Bremelanotide
Two peptides side-by-side — identity, evidence base, legal status and known adverse events.
Identity
Category
Cosmetic
Research other
CAS no.
214047-00-4
189691-06-3
Molecular weight
802.06 g/mol
1025.18 g/mol
Half-life
no data
2.7 h
Sequence
Palmitoyl-Lys-Thr-Thr-Lys-SerAc-Nle-c[Asp-His-D-Phe-Arg-Trp-Lys]-OHMechanism of action
Matrixyl
KTTKS is a fragment of the procollagen I sequence and appears to be part of a feedback mechanism in fibroblasts: elevated concentrations signal intact collagen synthesis and downregulate new synthesis, while low concentrations stimulate it. In cell-culture studies, stimulation of collagen types I/III, elastin, fibronectin and glycosaminoglycans has been documented. The palmitoyl modification is intended to improve skin penetration; effect at the site of action (dermal fibroblasts) depends on permeation.
Bremelanotide
Bremelanotide is a cyclic peptide that binds non-selectively to melanocortin receptors (MC1R through MC5R) — with highest affinity at MC4R in the central nervous system. The precise role of MC4R activation in sexual behaviour is not fully understood; animal data show effects on hypothalamic circuits. Peripheral effects (blood pressure, hyperpigmentation) are attributed to MC1R/MC2R.
Evidence base
Highest evidence
Human RCT
Human RCT
Studies
5
5
of which in humans
2
5
Effects recorded
3
3
Open conflicts
0
0
Documented adverse events
1
2