The ascorbateglutathione cycle coming of age TJ. Glutathione peroxidase is an important enzyme in cellular antioxidant defense systems, detoxifying peroxides and hydroperoxides. As a component of the glutathione cycle, it protects the liver from reactive oxygen metabolites. Selenocysteine GHK Cu 50mg Copper Peptide Peptides Alpha GHK Cu Peptide Foundry Premium Research Peptides GHK CU Tablets Dynamic3 Health Figure 1 from Glutathione redox cycle protects cultured endothelial cells against lysis by extracellularly generated hydrogen peroxide. Semantic Scholar