The glycyl-l-histidyl-l-lysine-Cu 2+ tripeptide complex attenuates lung inflammation and fibrosis in silicosis by targeting peroxiredoxin 6.

This study investigated whether the copper-bound tripeptide GHK-Cu (glycyl-l-histidyl-l-lysine-Cu²⁺) could reduce lung inflammation and fibrosis in silicosis — a serious occupational lung disease caused by chronic inhalation of crystalline silica (CS) with no approved specific treatment. Researchers first established a silicosis mouse model by exposing mice to CS, then assessed GHK-Cu's effects on lung inflammation and fibrosis. In parallel, they used the RAW264.7 macrophage cell line (an in vitro model of alveolar macrophages) to study cellular mechanisms. Using molecular docking and binding studies, they identified peroxiredoxin 6 (PRDX6) as a potential molecular target of GHK-Cu. The study reported that GHK-Cu bound to PRDX6 and attenuated CS-induced oxidative stress in alveolar macrophages, which was associated with reduced pulmonary inflammation and fibrosis in the mouse model. No significant systemic toxicity was observed in the treated animals. Key limitations include reliance on animal and cell-line models with no human clinical data, and the mechanistic link to PRDX6 requires further validation. The authors conclude that GHK-Cu warrants investigation as a potential therapeutic candidate for silicosis.

Why this grade: Evidence is drawn entirely from a mouse silicosis model and an in vitro macrophage cell line (RAW264.7), with no human subjects, providing only preclinical proof-of-concept data.