SPARC is a source of copper-binding peptides that stimulate angiogenesis

Lane TF, Iruela-Arispe ML, Johnson RS, Sage EH · The Journal of Cell Biology

Proteolysis of the matrix protein SPARC releases KGHK, GHK and longer peptides. KGHK carried most of the angiogenic activity, substituting the histidine reduced it, and the activity was sequence-specific and did not require pre-bound copper — a second matrix protein besides collagen α2(I) that can generate GHK when cut.

Population

Endothelial cells in cord-formation assays, with in-vivo angiogenesis assays

Intervention

SPARC-derived cationic peptides including KGHK and GHK

Comparator

Scrambled and His-substituted sequences; a second Cu-binding SPARC peptide without angiogenic activity

Limitations

Endothelial and angiogenesis endpoints; establishes the provenance of GHK as a matrix fragment, not any tissue-repair outcome.