Description
Reactive oxygen species (ROS) can oxidize proteins, lipids, and DNA, causing damage of their structure and function as well as cell injury.
Proteins are oxidised by free radicals, whereby the constituent amino acids are variously modified or degraded. The modifications result in new functional groups such as carbonyl or hydroxyl groups, which may lead to protein fragmentation, formation of protein-protein cross-linkages, disruption of the tertiary structure and loss of functional activity. In addition, ROS are directly associated with diseases like atherosclerosis, rheumatoid arthritis, Alzheimer’s and Parkinson’s disease as well as ageing and carcinogenesis. Protein carbonyls are formed by a variety of oxidative mechanisms and are sensitive indicators of oxidative injury. The quantity of protein carbonyls in a protein sample can be determined by derivatizing with dinitrophenylhydrazine (DNPH) and measuring the bound anti-DNPH antibodies.