Effect of hydrogen peroxide exposure on normal human erythrocyte deformability, morphology, surface characteristics, and spectrin-hemoglobin cross-linking.

Abstract

To further define the conditions for forming spectrin-hemoglobin cross-linking in human erythrocyte membranes and to examine its possible effects on membrane function, we incubated normal human erythrocytes for up to 3 h in concentrations of H202, varying from 45 to 180 ;.M, in an azide phosphate buffer, pH 7.4. The chemical changes observed indicated that methemoglobin formation occurred early and at a low concentration (45 MM). Morphologic changes characterized by increased echinocyte formation occurred in a dose-dependent fashion. In addition, decreased cell deformability commensurate with increased membrane rigidity was found. Finally, an increase in cell recognition as determined by monocyte phagocytosis and adherence in vitro, as well as decreased phosphatidylcholine accessibility to bee venom phospholipase A2, was found in H202-treated erythrocytes compared with controls. Both of these latter changes were closely correlated with the extent of spectrin-hemoglobin cross-linking.In addition to these protein-mediated interactions, lipid peroxidation also occurred after H202 exposure, as shown by generation of fluorescent amino propene derivatives. The addition of the antioxidant, butylated hydroxytoluene, decreased the fluorescent derivatives, but did not prevent the effects on membrane function. This suggests that lipid peroxidation, though present, was not necessary for the membrane changes found. In contrast, spectrin-hemoglobin aggregation and the alterations in membrane function were completely prevented by prior exposure of the erythrocytes to carbon monoxide.

Energy metabolism and lipid peroxidation of human erythrocytes as a function of increased oxidative stress

“…In fact, the correct energy balance of H 2 O 2 -treated erythrocytes was obtained only by taking into consideration concentrations of dephosphorylated metabolites, either those detected in erythrocyte extracts or those determined in the suspending medium. For instance, according to this calculation, the value of S NT + IMP + intra-and extra-cellular oxypurines and nucleosides was < 2030 mmol´L 21 and 1990 mmol´L 21 in control and 4 mm H 2 O 2 -treated erythrocytes, respectively. As reported in Fig.…”

Comparison of human red cell lysis by hypochlorous and hypobromous acids: insights into the mechanism of lysis

“…Because halohydrins are undetectable at these levels, it seems likely that modification of membrane and cytoskeletal proteins is responsible for haemolysis. It is interesting that studies with different oxidative systems have also found that protein modification, rather than lipid peroxidation, is associated with haemolysis [32,39,40]. There were two major differences in the effects of HOBr and HOCl on membrane proteins : (1) with HOBr there was selective loss of band 3 that was almost complete at the lowest dose of oxidant (4 nmol per 10( cells) and (2) irreversible protein cross-linking of most of the proteins occurred more readily with HOBr.…”

The Oxidant Effects of Hyperbaric Oxygenation and Air Pollution in Erythrocyte Membranes (Hyperbaric Oxygenation in Air Pollution)

“…FOR cause oxidant-induced changes in the structure and function of erythrocyte membranes. Major changes reported by different researchers are lipid peroxidation, membrane protein-crosslinkings and oxidation of heme proteins resulting in their crosslinkings to skeletal proteins, i.e spectrin, actin, cytoplasmic component of band 3 (47)(48)(49)(50). Free oxygen radicals induced changes result in severe deteoriation of membrane structure and function causing increases in osmotic fragility ratios, accelerated cell aging and premature cell death ultimately.…”