Oxidant damage of the lipids and proteins of the erythrocyte membranes in unstable hemoglobin disease. Evidence for the role of lipid peroxidation.

Abstract

A B S T R A C T Since unstable hemoglobins have been considered a source of reactive oxygen radicals, and oxidative membrane damage a prehemolytic event,we examined the erythrocyte membranes of six patients (three splenectomized) with hemoglobin Koln disease. In the hydrogen peroxide stress test, the patients' erythrocytes generated more than twice the malonyldialdehyde (a lipid peroxidative product) than control erythrocytes. Fluorescence spectra of lipid extracts of the patients' erythrocytes showed an excitation maximum at 400 nm and an emission maximum of 460 nm, characteristic of malonyldialdehyde lipid adducts. Two types of membrane polypeptide aggregates were found in the erythrocytes of the splenectomized patients. The first, which were dissociable by treatment with mercaptoethanol, contained disulfidelinked spectrin, band 3 and globin. The second, not dissociable by mercaptoethanol, had an amino acid composition similar to that of erythrocyte membranes and spectrin (unlike globin) and like that of aggregates produced by the action of malonyldialdehyde on normal erythrocyte membranes. Atomic absorption spectroscopy of hemoglobin Koln erythrocytes showed no increase in calcium content implying that these cross-links were not due to calcium-stimulated trans aggregates from splenectomized patients were less deformable while aggregate-free erythrocytes from nonsplenectomized patients had normal deformability. We conclude that the erythrocyte membranes in hemoglobin Koln disease show evidence of lipid peroxidation with production of malonyldialdehyde, and that the nondissociable membrane aggregates formed in this disease are likely cross-linked by malonyldialdehyde. Because the erythrocytes containing membrane aggregates from splenectomized patients with unstable hemoglobin disease show decreased membrane deformability, we hypothesize that this abnormality results in premature erythrocyte destruction in vivo.

Membrane protein lesions in erythrocytes with Heinz bodies.

“…Unstable hemoglobin Koln erythrocyte membranes have been well documented by Flynn and colleagues to exhibit evidence of lipid and protein oxidation (20), and have increased protein thiol oxidation analagous to SS-RBCs as measured by Rank et al (19). Superoxide anion is readily produced by the autoxidation of hemoglobin Koln, a reaction which is favored in this intrinsically "unstable" hemoglobin because of its abnormal tertiary structure, a result of an amino acid substitution near the stabilizing heme pocket (p98; Val --Met).…”

Why Hemodialysis Patients Are in a Prooxidant State? What Could Be Done to Correct the Pro/Antioxidant Imbalance

“…Since membrane lipids are generally considered as the preferential targets for most oxidative stress, lipid peroxidation results in profound structural and functional cellular alterations. Such a phenomenon could be involved to explain the shortened red blood cell survival recognized in HD [47][48][49][50] and could also become a limitating factor in regard to the erythropoietin response. Moreover, iron overload is frequently associated with anemia and contributes to prooxidant state [51].…”

Antihaemolytic activity of thirty herbal extracts in mouse red blood cells

“…Red blood cells (RBCs) are the primary targets of free radicals, owing to their high membrane concentrations of polyunsaturated fatty acids (linoleic and arachidonic acids in particular) and O 2 transport associated with redox active haemoglobin molecules, which are potent promoters of ROS. Oxidation depletes membrane protein content, deforms RBCs, and disturbs microcirculation (1)(2)(3)(4). It is also implicated in haemolysis (5).…”