The tripeptide GHKCu complex ameliorates lipopolysaccharideinduced acute lung injury in mice Oncotarget What are GHK cu (Glycyl Histidyl Lysine Copper) injections? GHK Cu vs AHK Cu: Which Copper Peptide Is More Effective? GHK Cu vs AHK Cu: Which Copper Peptide Is More Effective? GHK Cu is a naturally occurring tripeptide in human plasma. Levels average 200 ng ml at age 20 and drop to 80 ng ml by age 60 (Pickart et al., 2020). That decline tracks with