The Effect of the Human Peptide GHK on Gene Expression Relevant to Nervous System Function and Cognitive Decline Frontiers Exploring the beneficial effects of GHK Cu on an experimental model of colitis and the underlying mechanisms Intermediate Cu(II) Thiolate Species in the Reduction of Cu(II)GHK by Glutathione: A Handy Chelate for Biological Cu(II) Reduction Inorganic Chemistry New Biotinylated GHK and Related Copper(II) Complex: Antioxidant and Antiglycant Properties In Vitro against Neurodegenerative Disorders TOLERANCE & TACHYPHYLAXIS