Reversible oxidation of mitochondrial peroxiredoxin 3 in mouse heart subjected to ischemia and reperfusion.

Peroxiredoxins decompose peroxides through reversible oxidation of their active site cysteines. The redox state of the 2-Cys peroxiredoxins, 1, 2 and 3, was investigated in mouse hearts undergoing ischemia and reperfusion in a Langendorff system. The peroxiredoxins were predominantly reduced in control hearts. Mitochondrial peroxiredoxin 3 underwent significant oxidation to its disulfide-linked dimer during ischemia. Oxidation was largely reversed during reperfusion. No redox changes in cytoplasmic peroxiredoxins 1 and 2 were apparent. Peroxiredoxin 3 oxidation suggests localized mitochondrial generation of reactive oxidants during ischemia. This local antioxidant activity of peroxiredoxin 3 may have a role in maintaining cardiac function.