Figure 3.

Schematic representation whereby redox imbalance may induce damage in cells. Reactive oxygen species (ROS) are formed by the addition of electrons to the oxygen molecule leading to the formation of different ROS. Oxidative stress takes place in cells and tissues as a result of an imbalance between oxidants and antioxidants in favor of the former. Oxidative damage in tissues is induced through several mechanisms such as peroxidation of membrane lipids, alterations in nuclear DNA, or oxidation of cell proteins.