The glycyl-l-histidyl-l-lysine-Cu2+ tripeptide complex attenuates lung inflammation and fibrosis in silicosis by targeting peroxiredoxin 6

Redox Biol. 2024 Sep:75:103237. doi: 10.1016/j.redox.2024.103237. Epub 2024 Jun 14.

Abstract

Silicosis is the most common type of pneumoconiosis, having a high incidence in workers chronically exposed to crystalline silica (CS). No specific medication exists for this condition. GHK, a tripeptide naturally occurring in human blood and urine, has antioxidant effects. We aimed to investigate the therapeutic effect of GHK-Cu on silicosis and its potential underlying molecular mechanism. An experimental silicosis mouse model was established to observe the effects of GHK-Cu on lung inflammation and fibrosis. Moreover, the effects of GHK-Cu on the alveolar macrophages (AM) were examined using the RAW264.7 cell line. Its molecular target, peroxiredoxin 6 (PRDX6), has been identified, and GHK-Cu can bind to PRDX6, thus attenuating lung inflammation and fibrosis in silicosis mice without significant systemic toxicity. These effects were partly related to the inhibition of the CS-induced oxidative stress in AM induced by GHK-Cu. Thus, our results suggest that GHK-Cu acts as a potential drug by attenuating alveolar macrophage oxidative stress. This, in turn, attenuates the progression of pulmonary inflammation and fibrosis, which provides a reference for the treatment of silicosis.

Keywords: GHK-Cu; Macrophage; Oxidative stress; PRDX6; Silicosis.

MeSH terms

  • Animals
  • Antioxidants / pharmacology
  • Copper* / chemistry
  • Disease Models, Animal*
  • Humans
  • Macrophages, Alveolar* / drug effects
  • Macrophages, Alveolar* / metabolism
  • Male
  • Mice
  • Oligopeptides* / pharmacology
  • Oxidative Stress* / drug effects
  • Peroxiredoxin VI* / metabolism
  • Pneumonia / drug therapy
  • Pneumonia / metabolism
  • Pneumonia / pathology
  • Pulmonary Fibrosis / drug therapy
  • Pulmonary Fibrosis / metabolism
  • Pulmonary Fibrosis / pathology
  • RAW 264.7 Cells
  • Silicosis* / drug therapy
  • Silicosis* / metabolism
  • Silicosis* / pathology

Substances

  • Copper
  • Oligopeptides
  • glycyl-histidyl-lysine
  • Peroxiredoxin VI
  • Antioxidants