Nitric oxide and nitroxides can act as efficient scavengers of protein-derived free radicals
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Nitric oxide and nitroxides can act as efficient scavengers of protein-derived free radicals. / Lam, Magdalena A; Pattison, David I; Bottle, Steven E; Keddie, Daniel J; Davies, Michael Jonathan.
In: Chemical Research in Toxicology, Vol. 21, No. 11, 11.2008, p. 2111-9.Research output: Contribution to journal › Journal article › Research › peer-review
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TY - JOUR
T1 - Nitric oxide and nitroxides can act as efficient scavengers of protein-derived free radicals
AU - Lam, Magdalena A
AU - Pattison, David I
AU - Bottle, Steven E
AU - Keddie, Daniel J
AU - Davies, Michael Jonathan
PY - 2008/11
Y1 - 2008/11
N2 - Nitric oxide ((*)NO) may act as either a pro-oxidant or an antioxidant in biological systems. Although (*)NO and nitroxide radicals react slowly with most molecules, they react at near diffusion-controlled rates with other radicals and may therefore be efficient protective agents. This study assessed the ability of (*)NO and nitroxides to intercept specific protein-derived radicals and compared the efficacy of these species. Three protein radical systems were investigated as follows: BSA-derived radicals generated via radical transfer from H(2)O(2)-activated horseradish peroxidase, radicals formed on myoglobin via reaction with H(2)O(2), and carbon-centered radicals formed from amino acid hydroperoxides on exposure to Fe(2+)-EDTA. In each case, radicals were generated in the absence or presence of (*)NO or nitroxides of different size and charge. Concentration-dependent loss of the protein radicals was detected by electron paramagnetic resonance with both (*)NO and nitroxides and time-dependent consumption of (*)NO using an (*)NO electrode. The protein oxidation product dityrosine was significantly reduced by (*)NO and nitroxides, and 3,4-dihydroxyphenylalanine levels were reduced by nitroxides but not (*)NO. Overall, these studies demonstrate that (*)NO and nitroxides are efficient near-stoichiometric scavengers of protein radicals and, hence, are potential protective agents against protein oxidation reactions and resulting damage. These reactions show little dependence on nitroxide structure or charge.
AB - Nitric oxide ((*)NO) may act as either a pro-oxidant or an antioxidant in biological systems. Although (*)NO and nitroxide radicals react slowly with most molecules, they react at near diffusion-controlled rates with other radicals and may therefore be efficient protective agents. This study assessed the ability of (*)NO and nitroxides to intercept specific protein-derived radicals and compared the efficacy of these species. Three protein radical systems were investigated as follows: BSA-derived radicals generated via radical transfer from H(2)O(2)-activated horseradish peroxidase, radicals formed on myoglobin via reaction with H(2)O(2), and carbon-centered radicals formed from amino acid hydroperoxides on exposure to Fe(2+)-EDTA. In each case, radicals were generated in the absence or presence of (*)NO or nitroxides of different size and charge. Concentration-dependent loss of the protein radicals was detected by electron paramagnetic resonance with both (*)NO and nitroxides and time-dependent consumption of (*)NO using an (*)NO electrode. The protein oxidation product dityrosine was significantly reduced by (*)NO and nitroxides, and 3,4-dihydroxyphenylalanine levels were reduced by nitroxides but not (*)NO. Overall, these studies demonstrate that (*)NO and nitroxides are efficient near-stoichiometric scavengers of protein radicals and, hence, are potential protective agents against protein oxidation reactions and resulting damage. These reactions show little dependence on nitroxide structure or charge.
KW - Cyclic N-Oxides
KW - Electron Spin Resonance Spectroscopy
KW - Free Radical Scavengers
KW - Free Radicals
KW - Hydrogen Peroxide
KW - Nitric Oxide
KW - Nitrogen Oxides
KW - Oxidation-Reduction
KW - Proteins
U2 - 10.1021/tx800183t
DO - 10.1021/tx800183t
M3 - Journal article
C2 - 18834151
VL - 21
SP - 2111
EP - 2119
JO - Chemical Research in Toxicology
JF - Chemical Research in Toxicology
SN - 0893-228X
IS - 11
ER -
ID: 129670584