69
Views
82
CrossRef citations to date
0
Altmetric
Original Article

Nitroxide Sod-Mimics: Modes of Action

, , , , &
Pages 187-194 | Published online: 07 Jul 2009
 

Abstract

Low molecular weight superoxide dismutase mimics have been shown to afford protection from oxidative damage. Such SOD-mimics can readily permeate cell membrane achieving sufficiently high levels both inside and outside the cell to effectively detoxify intracellular O2. Preliminary findings also indicated that metal-based and metal-free SOD-mimics can protect hypoxic cells from H2O2-induced damage. The present study explored the possibility that SOD-mimics such as desferrioxamine-Mn(III) chelate [DF-Mn] or cyclic nitroxide stable free radicals could protect from O2-independent damage. Killing of monolayered V79 Chinese hamster cells was induced by H2O2 or by t-butyl hydroperoxide (t-BHP) and assayed clonogenically. Neither catalase nor native SOD protected the cells from t-BHP. In contrast. both DF-Mn and cyclic nitroxides protected suggesting cytotoxic processes independent of O2 or of O2 -derived active species. The inhibition of the damage by both metal-free and metal-based SOD mimics is attributable to either SOD-mimic reacting with reduced transition metal to block the Fenton reaction and/or intercepting and detoxifying intracellular organic free radicals.

Reprints and Corporate Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

To request a reprint or corporate permissions for this article, please click on the relevant link below:

Academic Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

Obtain permissions instantly via Rightslink by clicking on the button below:

If you are unable to obtain permissions via Rightslink, please complete and submit this Permissions form. For more information, please visit our Permissions help page.