Matrikine
A peptide fragment released during extracellular matrix degradation that acts as a signalling molecule, stimulating cells to produce new matrix components. Matrikines represent the body's natural repair signals. Synthetic matrikine-inspired peptides are used in cosmeceutical products targeting skin ageing.
Technical Context
Matrikines are peptide fragments released during ECM degradation that act as signalling molecules, triggering cellular responses to repair the damaged matrix. Key concept: the ECM is not merely structural but contains embedded biological information — specific proteolytic fragments activate cell surface receptors (integrins, elastin-binding protein, CD44) to stimulate matrix synthesis, cell migration, and proliferation. Examples: the GFOGER sequence in type I collagen binds integrin α2β1 to promote cell adhesion and differentiation; the VGVAPG sequence in elastin binds the elastin-binding protein to stimulate fibroblast chemotaxis and MMP-1 secretion; and the RGD sequence in fibronectin binds multiple integrins to regulate cell adhesion. Cosmeceutical matrikine-inspired peptides: palmitoyl pentapeptide-4 (KTTKS) is a matrikine derived from type I collagen's C-terminal propeptide — it signals fibroblasts to increase collagen production.