Known as a mitochondrial peptide, it works at the cellular level to regulate how the body produces and uses energy
The enzyme glutathione peroxidase (Sies and Jones 2020) is responsible for maintaining melatonin within the oxidoreduction redox cycle
Stand Genomic Sci 8(2):239254
Rakow A, Kowski A, Treskatsch S, et al
Thats why careful experiments spread doses across at least three orders of magnitude to find the sweet spot, which moves based on the copper-to-peptide ratio, the buffer used, and how much serum sits in the media
A large share of the accessible, highly-cited GHK-Cu literature consists of review articles authored by the same small group principally Loren Pickart, the compounds discoverer, with co-authors, published across several journals between roughly 2012 and 2018