|
|
Blood, 15 March 2007, Vol. 109, No. 6, pp. 2611-2617.
Prepublished online as a Blood First Edition Paper on November 14, 2006; DOI 10.1182/blood-2006-09-048728.
Previous Article | Table of Contents | Next Article 
RED CELLS
Peroxiredoxin 2 functions as a noncatalytic scavenger of low-level hydrogen peroxide in the erythrocyte
Felicia M. Low1,
Mark B. Hampton1,
Alexander V. Peskin1, and
Christine C. Winterbourn1
1 Free Radical Research Group, Department of Pathology, Christchurch School of Medicine & Health Sciences, University of Otago, Christchurch, New Zealand
Peroxiredoxin 2 (Prx2), a thiol-dependent peroxidase, is the third most abundant protein in the erythrocyte, and its absence in knock-out mice gives rise to hemolytic anemia. We have found that in human erythrocytes, Prx2 was extremely sensitive to oxidation by H2O2, as dimerization was observed after exposure of 5 x 106 cells/mL to 0.5 µM H2O2. In contrast to Prx2 in Jurkat T lymphocytes, Prx2 was resistant to overoxidation (oxidation of the cysteine thiol to a sulfinic/sulfonic acid) in erythrocytes. Reduction of dimerized Prx2 in the erythrocyte occurred very slowly, with reversal occurring gradually over a 20-minute period. Very low thioredoxin reductase activity was detected in hemolysates. We postulate that this limits the rate of Prx2 regeneration, and this inefficiency in recycling prevents the overoxidation of Prx2. We also found that Prx2 was oxidized by endogenously generated H2O2, which was mainly derived from hemoglobin autoxidation. Our results demonstrate that in the erythrocyte Prx2 is extremely efficient at scavenging H2O2 noncatalytically. Although it does not act as a classical antioxidant enzyme, its high concentration and substrate sensitivity enable it to handle low H2O2 concentrations efficiently. These unique redox properties may account for its nonredundant role in erythrocyte defense against oxidative stress.

CiteULike Connotea Del.icio.us Digg Reddit Technorati What's this?
This article has been cited by other articles:

|
 |

|
 |
 
T. Thum and J. Borlak
LOX-1 Receptor Blockade Abrogates oxLDL-induced Oxidative DNA Damage and Prevents Activation of the Transcriptional Repressor Oct-1 in Human Coronary Arterial Endothelium
J. Biol. Chem.,
July 11, 2008;
283(28):
19456 - 19464.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
E. Schroder, J. P. Brennan, and P. Eaton
Cardiac peroxiredoxins undergo complex modifications during cardiac oxidant stress
Am J Physiol Heart Circ Physiol,
July 1, 2008;
295(1):
H425 - H433.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. Reinartz, Z. Ding, U. Flogel, A. Godecke, and J. Schrader
Nitrosative Stress Leads to Protein Glutathiolation, Increased S-Nitrosation, and Up-regulation of Peroxiredoxins in the Heart
J. Biol. Chem.,
June 20, 2008;
283(25):
17440 - 17449.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
K. Buchholz, R. H. Schirmer, J. K. Eubel, M. B. Akoachere, T. Dandekar, K. Becker, and S. Gromer
Interactions of Methylene Blue with Human Disulfide Reductases and Their Orthologues from Plasmodium falciparum
Antimicrob. Agents Chemother.,
January 1, 2008;
52(1):
183 - 191.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J. Fang, T. Nakamura, D.-H. Cho, Z. Gu, and S. A. Lipton
S-nitrosylation of peroxiredoxin 2 promotes oxidative stress-induced neuronal cell death in Parkinson's disease
PNAS,
November 20, 2007;
104(47):
18742 - 18747.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
T. R. Hurd, T. A. Prime, M. E. Harbour, K. S. Lilley, and M. P. Murphy
Detection of Reactive Oxygen Species-sensitive Thiol Proteins by Redox Difference Gel Electrophoresis: IMPLICATIONS FOR MITOCHONDRIAL REDOX SIGNALING
J. Biol. Chem.,
July 27, 2007;
282(30):
22040 - 22051.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
A. V. Peskin, F. M. Low, L. N. Paton, G. J. Maghzal, M. B. Hampton, and C. C. Winterbourn
The High Reactivity of Peroxiredoxin 2 with H2O2 Is Not Reflected in Its Reaction with Other Oxidants and Thiol Reagents
J. Biol. Chem.,
April 20, 2007;
282(16):
11885 - 11892.
[Abstract]
[Full Text]
[PDF]
|
 |
|
| |