GHK-Cu (Copper peptides) are naturally occurring compounds and can also be synthesized by combining copper and amino acids. Copper peptides stimulate the rapid production of collagen and fibroblasts, which give our skin elasticity. This, in turn, allows the enzymes to firm, smooth, and soften rapidly, helping reduce the signs of aging. It also stimulates blood vessel and nerve outgrowth and glycosaminoglycan synthesis.