Oxidative stress: impact in redox biology and medicine
The field of oxidative stress research embraces chemistry, biochemistry, cell biology, physiology and pathophysiology, all the way to medicine and health and disease research. “Oxidative stress is an imbalance between oxidants and antioxidants in favor of the oxidants, leading to a disruption of redox signaling and control and/or molecular damage” (Sies, H., Jones, D. (2007) in: Encyclopedia of Stress (Fink, G., ed.), 2nd Ed., Vol.3, 45-48). The concept of oxidative stress is presented and discussed in context of current developments. Recent research on molecular redox switches governing oxidative stress responses provides further mechanistic insight in redox biology. The fundamental importance of linking redox shifts to phosphorylation/dephosphorylation signaling is being more fully appreciated. The redox relationships by which biological systems are organized have recently been conceptualized under four principles which, together, make up the ‘Redox Code’. On the more practical side, cautious use of terminology and methods is recommended regarding so-called ROS, reactive oxygen species, and RNS, reactive nitrogen species. The major role in antioxidant defense is fulfilled by antioxidant enzymes, not by small-molecule antioxidant compounds.
KEY WORDS: Oxidative stress; Redox biology; Medicine