SciELO Brasil Oxidative stress: molecular perception and transduction of signals triggering antioxidant gene defenses Oxidative stress: molecular perception and transduction of signals triggering antioxidant gene defenses File:Glutathione Reductase and Peroxidase Graphic.jpg Wikimedia Commons Glutathione Reductase (GR) Assay Kit (ab83461) Abcam Assay for quantitative determination of glutathione and glutathione disulfide levels using enzymatic recycling method Nature Protocols Glutathione System from Cyanobacteria to Higher Eukaryotes Encyclopedia MDPI 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