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. 2020 Sep 10;9(9):852.
doi: 10.3390/antiox9090852.

Oxidative Stress: Concept and Some Practical Aspects

Helmut Sies  1   2
Affiliations

Oxidative Stress: Concept and Some Practical Aspects

Helmut Sies. Antioxidants (Basel). .

Abstract

Oxidative stress is defined as "an imbalance between oxidants and antioxidants in favor of the oxidants, leading to a disruption of redox signaling and control and/or molecular damage". This Commentary presents basic features of this global concept which has attracted interest in biology and medicine. The term "antioxidants" in cellular defense against oxidants predominantly includes antioxidant enzymes with their substrates and coenzymes. Exogenous low-molecular-mass compounds also have a role, but this is more limited. Multiple biomarkers of damage due to oxidative stress have been identified for different molecular classes (protein, lipid, carbohydrate, and DNA), and the current state of practical aspects in health and disease is delineated.

Keywords: antioxidants; biomarkers; oxidative stress.

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Conflict of interest statement

The author declares no conflict of interest.

Figures

Figure 1
Figure 1
Oxidative stress and its relationship to redox signaling. Physiological (low) oxidant exposure addresses specific (highly-reactive) targets, whereas supraphysiological (high) exposure addresses unspecific targets. Adaptive responses counteract. Further important oxidants are generated in secondary reactions; e.g., ONOOH, from O2·− and ·NO, or HOCl, from H2O2 and Cl−. Modified from Ref. [6]. Creative Commons License.
Figure 2
Figure 2
Clinical relevance of biomarkers of oxidative stress. Color coding on right: Protein (green), lipid (blue), and DNA (red) biomarkers are analyzed for various diseases. Color coding on top: results from cluster analysis. Data compiled from Frijhoff et al. [26], presented as Figure 11 in Ref. [5], with permission.
See this image and copyright information in PMC

References

    1. Sies H., editor. Oxidative Stress. Academic Press; London, UK: 1985. Oxidative stress: Introductory remarks; pp. 1–8.
    1. Sies H. On the history of oxidative stress: Concept and some aspects of current development. Curr. Opin. Toxicol. 2018;7:122–126. doi: 10.1016/j.cotox.2018.01.002. - DOI
    1. Halliwell B., Gutteridge J.M.C. Free Radicals in Biology and Medicine. Oxford University Press; Oxford, UK: 2015.
    1. Sies H., Jones D.P. Oxidative stress. In: Fink G., editor. Encyclopedia of Stress. 2nd ed. Volume 3. Elsevier; Amsterdam, The Netherlands: 2007. pp. 45–48.
    1. Sies H., Berndt C., Jones D.P. Oxidative stress. Annu. Rev. Biochem. 2017;86:715–748. doi: 10.1146/annurev-biochem-061516-045037. - DOI - PubMed

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