A gene expression signature of emphysema-related lung destruction and its reversal by the tripeptide GHK

Campbell JD, McDonough JE, Zeskind JE, Hackett TL, Pechkovsky DV, Brandsma CA, Suzuki M, Lenburg ME, Hogg JC, Spira A · Genome Medicine

127 genes tracked regional emphysema severity; repair-associated TGF-β, actin-organisation and integrin genes fell as destruction rose. The Connectivity Map nominated GHK as a compound reversing that signature, and GHK applied to fibroblasts reproduced TGF-β-induced expression, organised the actin cytoskeleton, raised integrin β1, and restored collagen-I contraction by COPD-derived fibroblasts. This is the primary source behind the widely repeated claim that GHK modulates thousands of genes.

Population

64 lung-tissue samples from 8 COPD lungs graded for regional emphysema severity by micro-CT, plus human lung fibroblasts from COPD and former-smoker donors

Intervention

Connectivity Map query against the emphysema-severity expression signature, then GHK applied to cultured fibroblasts

Comparator

Untreated fibroblasts; TGF-β as a positive control

Limitations

The Connectivity Map step is an in-silico match of transcriptional signatures generated in cultured cell lines at a single high dose. It nominates candidate compounds; it measures no clinical outcome, no dose-response and no tissue. Eight lungs. The fibroblast work that follows is the paper's only experimental GHK evidence.