Linkage of cytosolic peroxiredoxin 2 to erythrocyte membrane imposed by hydrogen peroxide-induced oxidative stress

Abstract

Human erythrocyte peroxiredoxin 2 (Prx2) is a typical 2-cys cytosolic peroxiredoxin with thiol-dependent hydrogen peroxide scavenger activity. In a previous work, we reported Prx2 erythrocyte membrane linkage in some Hereditary Spherocytosis patients and that it seemed to be related to oxidative stress. The aim of the present work was to determine if Prx2 linkage to erythrocyte membrane could be induced by oxidative stress mediated by H(2)O(2) and to further understand how and why this process occurs. We performed in vitro assays in which catalase or both Hb autoxidation and catalase were inhibited, under H(2)O(2)-induced oxidative stress conditions. Erythrocyte membrane linked Prx2 was detected by immunoblotting and quantified by densitometry. As oxidative stress markers, we determined membrane bound hemoglobin and lipid peroxidation, and we found that their values increased with H(2)O(2) concentration. Prx2 linkage to the membrane also rose with increasing H(2)O(2) concentration, and was only observed when the oxidized form of the enzyme was present in the cytosol. Oxidized Hb and Prx2 membrane linkages appear to be independent processes, although, both result from oxidative stress and may be useful as oxidative stress and/or erythrocyte damage/senescence markers.

Potentially antigenic RBC membrane proteins in dogs with primary immune‐mediated hemolytic anemia

“…Prx 2 is a member of the 2‐cysteine peroxidase family of anti‐oxidants, and it serves a non‐redundant role in anti‐oxidant defense in RBCs . Typically, Prx 2 exists in the cytosol, but in severe oxidative stress, it becomes physically linked to the RBC membrane . As membrane‐associated proteins would be more easily recognized and attacked by the immune system than cytosolic proteins, the presence of immunoreactivity against Prx 2 indicates that it is most likely membrane‐associated during IMHA.…”

Role of peroxiredoxin-2 in protecting RBCs from hydrogen peroxide-induced oxidative stress

“…Considering the high concentration of PRDX2 in RBC, the 5% is not negligible. It has further been shown that the level of PRDX2 association with the membrane is affected by oxidative stress [48,49] as well as hypoxia [50]. Membrane association of PRDX2 thought to involve the C- terminal region of PRDX2,has been shown to react with lipid hydroperoxides [33].…”

Peroxiredoxin‐2 as a candidate biomarker to test oxidative stress levels of stored red blood cells under blood bank conditions

“…Second, the dimeric conformation of Prx2 gives important information on the oxidative state of the protein indicating a reduced H 2 O 2 scavenger activity. Moreover its estimation can exclude possible contaminations from cytosolic Prx2 portion because dimer has never been detected in control RBC ghosts 48,54 . Indeed, in cytosol Prx2 exists in a redox‐linked oligomerization state with the reduced enzyme (monomer) forming the (α2) 5 decamer exclusively.…”