Oxidative stress and brain diseases: Biomarkers and analytical methodologies

Oxidative stress is the imbalance between production of reactive oxygen species (ROS) and ability of the biological systems to readily detoxify the reactive intermediates or to repair the resulting damage. Disturbances in the normal redox state of tissues can cause toxic effects through the production of peroxides and free radicals that damage all components of the cell including proteins, lipids and DNA. Furthermore, some ROS can even act as messengers through a phenomenon called redox signaling. In humans, oxidative stress is involved in many pathogenic mechanisms triggering aging processes and affecting organs as liver and brain. In the present paper, the role of oxidative stress is considered in relation to three neurodegenerative pathologies those are the most common in western countries and have analogies in brain damages notwithstanding different etiologies: i) Alcohol abuse by environmental etiology, ii) Down Syndrome by genetic etiology, and iii) Alzheimer's disease by age-related etiology. Recent studies have described the results about application of different biomarkers of oxidative stress to study these brain pathologies. The present paper deals with the diagnostic applications of the oxidative-stress biomarkers like malondialdehyde. heat shock protein. ROS and retinol binding protein in clinical handling of patients and discusses their diagnostic power taking into account cost/benefit ratio too.