Assessment of the state of oxidative stress

Oxidative stress, an imbalance toward the pro-oxidant side of the pro-oxidant/antioxidant homeostasis, occurs in several human diseases. The assessment of the state of oxidative stress could be done by measuring the concentration of various pro-oxidants, i.e., reactive oxygen and nitrogen species, and measuring various kinds of metabolites of the biological molecules damaged by ROS and/or RNS, such as nuclear acids, lipids and protein. It also can be done by detecting the antioxidant agents including enzymes such as catalase, superoxide dismutase, glutathione peroxidase, and numerous non-enzymatic antioxidants, including vitamins A, E and C, glutathione, ubiquinone, metallothionein and thioredoxin. As redox reaction is associated with oxidative stress, the apparent redox potential reflecting the redox state of the body can also be used to judge the overall state of oxidative stress. The combination of the redox potential and reduction capacity for various redox pairs, e.g. GSSG/GSH redox pair, may be a useful approach for the assessment of the state of oxidative stresss.