Journal of Clinical and Experimental Investigations

Abstract

Oxidative stress is described as disturbed oxidative balance between increased reactive oxygen species such as hydroxyl radical (OH•), superoxide radical (O₂−), hydrogen peroxide (H₂O₂) which occurs during normal cellular metabolism and decreased antioxidants which have scavenging effects on free radicals. Reactive oxygen species resulted from increased oxidative stress attacks on to the double bonds of lipids, proteins and DNA bases, removing one hydrogen atom from structure and initiate to oxidative chain reactions. This process leads to cellular damage and death damaging intracellular macromolecules such as lipids, proteins and DNA. The damage of free radicals is detected measuring oxidative products such as malondialdehyde (MDA), protein carbonyl (PCO) and 8-hydroxyguanine derivatives (8-OHG, 8-hidroksi-2′-deoksiguanozin) in body fluids and various tissues.
Although considerable amount of studies in this field, the effects of oxidative stress on cellular structures still remain unknown. In this review, we aimed to evaluate the biochemical aspects of oxidative stress, antioxidant systems and their mechanism of actions and oxidative products.