Biological Indicators of Oxidative Stress [Malondialdehyde, Catalase, Glutathione Peroxidase, and Superoxide Dismutase] and Their Application in Nutrition

The imbalance between the oxidant and antioxidant systems leads to a biological condition defined as oxidative stress that contributes to the formation of reactive oxygen species, which are unstable molecules resulting from various processes in the body that can be highly harmful and cause a series of diseases. In this sense, the action of antioxidants becomes necessary, as they are responsible for inhibiting and reducing damage caused by free radicals in cells. However, it is possible to prevent the damage caused by exposure to pro-oxidant substances through the measurement of biological biomarkers, which are important in the evaluation of the redox state. In this chapter, we will discuss markers used to assess the capacity of free radical scavenging, such as catalase, glutathione peroxidase, and superoxide dismutase enzymes, in addition to malondialdehyde, a biomarker used to assess lipid peroxidation. Oxidative stress biomarkers have been studied in several pathologies and can help in the diagnosis and monitoring of the progression of these diseases.