Relationship between cell age, glutathione and cation concentrations in sheep erythrocytes with a normal and a defective transport system for amino acids.

Percoll density gradients were used to separate sheep erythrocytes according to cell age. Erythrocytes with low intracellular levels of glutathione (GSH) caused by an inherited deficiency of the System C amino acid transporter exhibited large age-related decreases in GSH and K+ content. In contrast, there was no age-related loss of intracellular GSH in normal sheep erythrocytes or in sheep erythrocytes with low GSH resulting from a diminished activity of gamma-glutamylcysteine synthetase. Loss of GSH from amino acid transport-deficient erythrocytes was paralleled by the progressive appearance of Heinz bodies in the cells, indicating an increased susceptibility to oxidative damage.

[Evaluation of the redox status of neoplastic patients]. / Valutazione dello stato ossido-riduttivo dei pazienti neoplastici.

Free radicals and peroxides of our organism, that are very unstable, are now recognized as a product of biological oxido-reductive processes. The evaluation of free radicals and peroxides in blood was done by counting Heinz-bodies (H.B.) (Beutler method). The Authors examined 40 healthy subjects, at rest, and 37 neoplastic patients (19 carcinomas, 10 leukemias, 8 lymphomas) at the admission to hospital. The results show that the rate per cent of H.B. in neoplastic patients is significantly higher than in healthy subjects. According to us, neoplastic patients have free radicals hematic levels higher than healthy volunteers.

[Formate incubation of red blood cells from glucose-6-phosphate-dehydrogenase-deficient patients]. / Formiatinkubation roter Blutzellen von Glukose-6-Phosphat-dehydrogenase-Defektträgern.

Attempts of incubating red blood cells of G6PD-defect carriers in 10 from 25 patients showed format in these blood samples is able under the elected conditions to suppress haemolysis, to reduce the numbers of Heinz's bodies and to enhance GSH-concentration. A more distinct efficiency could be observed in enzyme variants with instable temperatures and if kinetic properties had changed. Prevention of haemolysis is particularly suitable as a parameter because it will reflect all damages connected with an enhanced membrane permeability. The increase of GSH-concentration as an important equivalent of reduction in the metabolism of red blood cells may diminish the toxicity of damaging factors having an effect on oxidation. The number of Heinz's bodies is essential in those cases where oxidation products of haemoglobin are increasingly formed only under certain conditions of incubation. The findings allow a format therapy to be recommended for selected G6PD defects.

Heinz body anemia and methemoglobinemia in ponies given red maple (acer rubrum L.) leaves.

Ponies given dried red maple (Acer rubrum L.) leaves at a dose of 3.0 gm/kg body weight became ill and died one to five days after administration of the leaves. Two clinical patterns of disease were seen. Ponies given dried leaves collected after September 15 died by 18 hours, while ponies given dried leaves collected before September 15 became ill with a hemolytic syndrome and died by three to five days. Freshly harvested leaves administered immediately after collection did not produce disease in ponies, but when dried, they became toxic and remained so for at least 30 days. Overnight freezing did not alter the toxicity of the leaves. Leaves were toxic when administered at doses of 1.5 gm/kg of body weight. The clinical signs of ponies with the hemolytic syndrome included polypnea, tachycardia, icterus, cyanosis, scleral petechiation, and brownish discoloration of the urine and blood. Blood changes of ponies with the hemolytic syndrome included anemia, hemoglobinemia, Heinz bodies, depletion of erythrocyte reduced glutathione, increased erythrocyte fragility, and increased serum levels of aspartate amino transferase, sorbitol dehydrogenase, plasma protein, and bilirubin. Lesions of ponies that died from the hemolytic syndrome included icterus, centrilobular hepatic degeneration, hemoglobinemic nephrosis, and erythrophagocytosis by splenic, adrenal, and hepatic phagocytes. Only brownish discoloration of the blood and mild centrilobular hepatic degeneration were observed in the four ponies that died peracutely.

Decreased survival in vivo of diamide-incubated dog erythrocytes. A model of oxidant-induced hemolysis.

Erythrocytes from patients with chronic hemolytic variants of glucose-6-phosphate dehydrogenase (G-6-PD) deficiency have structural membrane protein abnormalities accompanied by decreased cell membrane deformability which we postulate represent the consequences of oxidant-induced membrane injury. To evaluate the pathophysiologic significance of oxidant-induced membrane injury, we studied the in vitro and in vivo effects of the thiol-oxidizing agent, diamide, on dog erythrocytes. In vitro incubation of dog erythrocytes with 0.4 mM diamide in Tris-buffered saline for 90 min at 37 degrees C resulted in depletion of GSH, formation of membrane polypeptide aggregates (440,000 and > 50,000,000 daltons) and decreased cell micropipette deformability, abnormalities similar to those observed in the erythrocytes of patients with chronic hemolytic variants of G-6-PD deficiency. In addition, diamide-incubated cells had increased viscosity and increased membrane specific gravity, but no change in ATP. Reinjection of 51Cr-labeled, diamide-incubated cells was followed by markedly shortened in vivo survival and splenic sequestration. Further incubation of diamide-incubated cells in 4 mM dithiothreitol reversed the membrane polypeptide aggregates, normalized micropipette deformability, decreased cell viscosity, prolonged in vivi survival, and decreased splenic sequestration. These studied demonstrate that diamide induces a partially reversible erythrocyte lesion which is a useful model of oxidant-induced membrane injury. They suggest that oxidant-induced erythrocyte membrane injury plays an important role in the pathophysiology of chronic hemolysis which accompanies some G-6-PD variants.

Sulphonamide as hemolysis-promoting factor in uremia.

Nine out of 39 uremic patients treated with sulphonamides because of urinary tract infection developed hemolysis. Heinz-bodies were seen in all cases. In uremic patients a defect of the HMP metabolic pathway renders these patients susceptible to hemolysis when treated with oxidant drugs.

Spectrophotometric method applicable to in vitro studies of Heinz body formation in erythrocytes.

A simple quantitative procedure is described for the estimation of Heinz body formation in erythrocytes, based on the spectrophotometric measurement of the amount of crystal violet absorbed by precipitated Heinz bodies. Good correlation is shown between this method and the counting of Heinz body-containing erythrocytes in a microscopical preparation. This technique is particularly applicable to in vitro studies of the comparative effects produced in the erythrocyte by oxidant agents.

Oxidant injury of caucasian glucose-6-phosphate dehydrogenase-deficient red blood cells by phagocytosing leukocytes during infection.

Patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency of red blood cells (RBC) may develop sudden hemolytic anemia during infection. Since phagocytizing polymorphonuclear leukocytes (PMN) are known to generate hydrogen peroxide, we explored the influence of this oxidant product of PMN on juxtaposed G6PD-deficient and normal RBC. The oxidant stress induced by phagocytosis depleted G6PD-deficient RBC of reduced glutathione (GSH) and this was associated with rapid removal of these cells from the circulation by the liver and spleen. No such effect was observed on normal RBC. Phagocytizing chronic granulomatous disease (CGD) PMN which lack hydrogen peroxide generation, failed to diminish GSH level in G6PD-deficient RBC. Thus, PMN can pose as a source of oxidant damage to G6PD-deficient RBC due to hydrogen peroxide generated during phagocytosis.