EPR Study of KO2 as a Source of Superoxide and •BMPO-OH/OOH Radical That Cleaves Plasmid DNA and Detects Radical Interaction with H2S and Se-Derivatives

Antioxidants

Miroslav Chovanec¹  Lenka Tomasova²  Marian Grman²  Karol Ondrias²  Anton Misak²  Claus Jacob³  Muhammad Jawad Nasim³  Vlasta Brezova⁴  Karol Luspai⁴ 

[1] Biomedical Research Center, Department of Genetics, Cancer Research Institute, Slovak Academy of Sciences, Dúbravská Cesta 9, 84505 Bratislava, Slovakia;Biomedical Research Center, Department of Molecular Physiology, Institute of Clinical and Translational Research, Slovak Academy of Sciences, Dúbravská Cesta 9, 84505 Bratislava, Slovakia;Division of Bioorganic Chemistry, School of Pharmacy, University of Saarland, D-66123 Saarbruecken, Germany;Institute of Physical Chemistry and Chemical Physics, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, 81237 Bratislava, Slovakia;

关键词: KO₂;    antioxidants;    EPR spectra simulation;    ^•BMPO-OOH spin adduct;    superoxide;    radical;   

DOI  :  10.3390/antiox10081286

来源: DOAJ

【 摘 要 】

Superoxide radical anion (O₂^•−) and its derivatives regulate numerous physiological and pathological processes, which are extensively studied. The aim of our work was to utilize KO₂ as a source of O₂^•− and the electron paramagnetic resonance (EPR) spin trapping 5-tert-butoxycarbonyl-5-methyl-1-pyrroline N-oxide (BMPO) technique for the preparation of ^•BMPO-OOH and/or ^•BMPO-OH radicals in water solution without DMSO. The method distinguishes the interactions of various compounds with ^•BMPO-OOH and/or ^•BMPO-OH radicals over time. Here, we show that the addition of a buffered BMPO-HCl mixture to powdered KO₂ formed relatively stable ^•BMPO-OOH and ^•BMPO-OH radicals and H₂O₂, where the ^•BMPO-OOH/OH ratio depended on the pH. At a final pH of ~6.5–8.0, the concentration of ^•BMPO-OOH radicals was ≥20 times higher than that of ^•BMPO-OH, whereas at pH 9.0–10.0, the ^•BMPO-OH radicals prevailed. The ^•BMPO-OOH/OH radicals effectively cleaved the plasmid DNA. H₂S decreased the concentration of ^•BMPO-OOH/OH radicals, whereas the selenium derivatives 1-methyl-4-(3-(phenylselanyl) propyl) piperazine and 1-methyl-4-(4-(phenylselanyl) butyl) piperazine increased the proportion of ^•BMPO-OH over the ^•BMPO-OOH radicals. In conclusion, the presented approach of using KO₂ as a source of O₂^•−/H₂O₂ and EPR spin trap BMPO for the preparation of ^•BMPO-OOH/OH radicals in a physiological solution could be useful to study the biological effects of radicals and their interactions with compounds.

【 授权许可】

Unknown