The Study On The Mechanism Of GHK-Cu Regulating Melanin Synthesis In Melanocytes

Oobjective:To study the effect of Glycyl-L-Histidyl-L-Lysine(GHK-Cu)in regulating melanocyte tyrosinase activity and melanin synthesisMethod:After confirming the activation effect of GHK-Cu on mushroom tyrosinase in vitro,further studies were done to transfect WM451 cells with GHK-Cu via liposome carriers.Intracellular concentration of GHK-Cu were measured at different carrier levels.Tyrosinase activity and melatonin concentration were determined using in-vitro dopa reaction method and NaOH lysis method,respectively.Guinea pig model was used to further study the effect of copper-peptide.After one month of treatment with topical medication containing different levels of copper peptide,pathological and ultrastructral changes in skin tissues were studied using biopsies,HE staining,and transmission electron microscope.Results:GHK-Cu showed an activation effect for mushroom tyrosinase.The enzyme activity reaches a plateau as copper peptide continues to increase.As contrasted with the control group,cells treated with copper-peptide showed a dose-dependent increase in copper iron.Liposome GHK-Cu transfection can activate tyrosinase within WM451 cells and significantly increase the intracellular melanin concentration.Histopathological results showed that topical application of GHK-Cu slightly increased pigmentation of the basal cell layer.The transmission electron microscope results showed a slight increase in the number and size of melanosomes in the treatment groups.Conclution:liposomes can be used as a GHK-Cue carrier to import copper-peptide into melanocytes.GHK-Cu can increase the tyrosinase activity and melanin level in melanocytes.