PDF) Effects of GHK Cu on MMP and TIMP Expression, Collagen and Elastin Production, and Facial Wrinkle Parameters GHK Cu All Natural Shampoo Conditioner Fleava GHK Cu Hair & Scalp Serum 2400mg 4% Less Shedding Neurogan Neurogan Health GHK Cu Liposomal 5 mg 50 cpsulas Nootrpicos Per GHK Cu is a copper peptide that plays a role in tissue repair and collagen synthesis. The result: improved texture, firmness, and overall skin quality.