What the research examined
An early GHK-Cu experiment measured collagen synthesis in fibroblast cultures. A later study examined copper-free GHK in keratinocytes and skin-equivalent models, reporting changes in proliferation-related and cellular markers. These experiments investigate different cells and molecular forms.
How to interpret the findings
Copper-free GHK and GHK-Cu should not be assumed identical. A measured cellular response is not a clinical skin outcome, and a skin-equivalent model remains an experimental system.
Research literature
- Stimulation of collagen synthesis in fibroblast cultures by the tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu2+.
FEBS letters · 1988 · PMID 3169264 - Stem cell recovering effect of copper-free GHK in skin.
Journal of peptide science : an official publication of the European Peptide Society · 2012 · PMID 23019153
Links open the indexed paper records. Summaries are based on those records and their available abstracts, not a systematic review or a full-text appraisal of every study.