Oxidative stress and human diseases: Origin, link, measurement, mechanisms, and biomarkers

Abstract

Oxidative stress has been related increasingly to the onset and/or progression of a growing number of human diseases. However, large studies on supplementation with anti-oxidants for prevention or treatment of different pathologies have yielded contradictory and mostly negative results, as documented by numerous meta-analyses and clinical trials. Here we analyze in detail the findings of these studies and discuss major aspects that, in our opinion, are likely to be responsible for these confounding data. With the belief that a clear correlation between disease and oxidative stress is far from being proven for most pathological conditions, our argument focuses on the following points: i) choice of biomarker(s) and/or the biological system(s) for the analyses; ii) pitfalls in pre-analytical and analytical methods for assessing oxidative stress; and iii) scientific misconduct. Eventually, suggestions aiming to obtain more convergent results on this topic are provided.

Keywords::

• Anti-oxidants
• bioanalytical validation
• biomarker(s) of oxidative stress
• clinical trials
• free radicals
• human diseases
• nitrosative stress
• oxidative damage
• oxidative stress
• reactive nitrogen species
• reactive oxygen species

Acknowledgements

The authors thank Maria-Theresia Suchy for technical assistance and Frank-Mathias Gutzki for performing GC-MS/MS analyses.

Declaration of interest

The authors report no conflicts of interest.