Five Peptides Every Endurance Athlete Should Understand The naturally occurring peptide GHK reverses age related fibrosis by modulating myofibroblast function He Aging Pathobiology and Therapeutics GHK CU Research Peptide Alpha Carbon Labs GHK Cu as a multifunctional copper peptide: synthesis routes, process engineering and emerging applications Systems Microbiology and Biomanufacturing Springer Nature Link