Metal chelators react also with reactive oxygen and nitrogen species
Aneta Balcerczyk1, Katarzyna Sowa, Grzegorz Bartosz
1Department of Molecular Biophysics, University of Lodz, Banacha 12/16, 90-237 Lodz, Poland. abal@biol.uni.lodz.pl
Biochemical and Biophysical Research Communications
|November 28, 2006
Summary
Chelators like desferrioxamine and SIH exhibit antioxidant properties, reducing radicals and reactive species. This finding necessitates careful interpretation of experiments involving antioxidants and metal ions.
Area of Science:
- Biochemistry
- Oxidative Stress Research
Background:
- Chelating agents are commonly used in biological research.
- Their potential antioxidant activity is often overlooked.
Purpose of the Study:
- To investigate the antioxidant properties of common chelators.
- To assess the impact of chelator antioxidant activity on experimental interpretations.
Main Methods:
- Evaluation of chelator reactions with ABTS radical cation.
- Assessment of chelator reactivity towards peroxyl radicals, peroxynitrite, and hypochlorite.
Main Results:
- Popular chelators, including desferrioxamine, SIH, EDTA, EGTA, DTPA, and NTA, demonstrated antioxidant capabilities.
- Desferrioxamine and SIH were identified as the most potent antioxidants.
- Chelators effectively reduced ABTS radical cation and reacted with various reactive oxygen and nitrogen species.
Conclusions:
- Chelators possess inherent antioxidant properties that can influence experimental outcomes.
- The antioxidant activity of chelators must be considered when interpreting studies on free radical reactions.
- Relying solely on antioxidant inhibition to infer metal ion involvement may be misleading due to chelator-based antioxidant effects.
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