Glutathione Peroxidase Assay Kit (Colorimetric)

Supplementary info

Activity summary

Glutathione Peroxidase (GPx) often referred to as GSH peroxidase is an essential enzyme in the cellular defense system against oxidative damage. It exists as a group of enzymes including the widely studied isoform GPx4. GPx has a molecular weight of approximately 20-23 kDa varying slightly depending on the isoform. This enzyme is localized in many tissues across different organs including the liver kidney and muscles. It catalyzes the reduction of hydrogen peroxide and organic hydroperoxides using glutathione (GSH) as a substrate preventing the formation of free radicals.

Biological function summary

The enzyme plays a significant role in the detoxification of reactive oxygen species. GPx does not usually form a complex with other proteins; instead it acts individually within cells to maintain the balance of oxidative and reductive forces. By converting harmful peroxides into non-toxic alcohols and water it protects cell membranes and other cellular components from oxidative damage. GPx activity is often measured in laboratories using assays to determine its efficiency in catalyzing these reactions.

Pathways

GPx engages in critical cellular antioxidant defense mechanisms. It is an integral part of the glutathione redox cycle where it partners with glutathione reductase another enzyme important for regenerating reduced glutathione. Additionally GPx links to the pentose phosphate pathway providing reduced NADPH necessary for maintaining glutathione in its reduced form. These pathways protect cells from oxidative stress and keep redox homeostasis in check.

Associated diseases and disorders

Alterations in GPx activity correlate with various health conditions. Researchers link decreased GPx activity to cardiovascular diseases and neurodegenerative disorders highlighting its importance in maintaining cellular health. In cardiovascular diseases the imbalance of oxidative stress pathways involves proteins like superoxide dismutase in addition to GPx worsening the effects of oxidative damage. In neurodegenerative disorders abnormal protein aggregations disturb GPx activities emphasizing the role of antioxidants in disease prevention and management.