GHK vs PEG-MGF

Cosmetic

Performance

Research Only

Research Only

GHK is a high-affinity ligand for copper(II), forming the GHK-Cu complex that mediates most of its documented biology. Via the copper-bound form, GHK is proposed to modulate expression of a large number of human genes (microarray and Broad Institute Connectivity Map analyses from Pickart's group), including pathways related to extracellular matrix remodeling, antioxidant response element induction, angiogenesis, and DNA repair. Reported in vitro and preclinical effects include stimulation of fibroblast collagen and glycosaminoglycan synthesis and acceleration of wound healing. The bare (non-copper) peptide is typically weaker than GHK-Cu in these assays and is generally assumed to acquire copper in serum-containing environments.

The MGF E-peptide acts locally on muscle satellite (stem) cells, promoting their proliferation and delaying terminal differentiation, which expands the progenitor pool available for fusion into damaged myofibers. Receptor-blocking studies by Yang & Goldspink (2002) indicated that the E-peptide acts through a receptor distinct from the classical IGF-1R, although the exact receptor remains unconfirmed — this is one reason MGF is mechanistically separable from mature IGF-1 or IGF-1 LR3. Conjugation of polyethylene glycol to the peptide reduces renal clearance and proteolysis, extending plasma half-life from minutes (native MGF) to several hours.

50–200 ppm topical (~0.005–0.02%)

200–500 mcg