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PubMed · 6466672

Decrease of transport of some polyols in sickle cells.

C T Craescu·R Cassoly·F Galacteros·C Prehu
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Abstract

This paper reports the results of kinetic studies on the inward net-flux of small non-electrolytes (ethylene glycol, glycerol and erythritol) in sickle cells as compared to normal erythrocytes. Net transport rates were evaluated by turbidimetric measurements for ethylene glycol and glycerol and by hematocrit monitoring for erythritol. A 2-fold and 4-fold reduction in the permeability coefficient for ethylene glycol and glycerol, respectively, were found in sickle cells as compared to normal erythrocytes. In contrast, no significant changes in erythritol transport kinetics were observed. The dependence of glycerol permeability on temperature, pH and oxygenation is the same in both types of cells. A significant correlation was observed between glycerol permeability and cell density only for sickle cells. The results indicate that irreversible modifications of membrane proteins, responsible for the glycerol and ethylene glycol transport, do occur in sickle cells.

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Anemia, Sickle CellBiological TransportCell Membrane PermeabilityChloromercuribenzoatesErythritolErythrocyte MembraneEthylene GlycolsGlycerolHumansHydrogen-Ion ConcentrationKineticsOxygenTemperatureJournal Article

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C T Craescu, R Cassoly, F Galacteros, C Prehu. 1984-09-05. Decrease of transport of some polyols in sickle cells.. https://doi.org/10.1016/0005-2736(84)90183-4

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Anemia, Sickle Cell↗
PubMed1992

High expression of human beta S- and alpha-globins in transgenic mice: erythrocyte abnormalities, organ damage, and the effect of hypoxia.

A line of transgenic mice with two cointegrated transgenes, the human beta S- and alpha 2-globin genes, linked to the beta-globin locus control region was produced and bred with mice carrying a deletion of the mouse beta major-globin gene. In transgenic mice homozygous for the beta major deletion (alpha H beta S[beta MDD]; where alpha H is human alpha-globin and MD is mouse deletion), 72.5 +/- 2.4% (mean +/- SD) of the beta-chains are beta S and the ratio of alpha H- to beta S-globin was 0.73. Introduction of a heterozygous mouse alpha-globin deletion into mice homozygous for the beta major deletion (alpha H beta S[alpha MD beta MDD]) resulted in 65.1 +/- 8.5% beta S and a human alpha/beta ratio of 0.89 +/- 0.2. Sickling occurs in 95% of erythrocytes from alpha H beta S[beta MDD] mice after slow deoxygenation. Transmission electron microscopy revealed polymer fiber formation but not fascicles of fiber. Increased organ weight was noted in lung, spleen, and kidney of transgenic mice vs. controls that may be due to hypertrophy or increased blood volume in the lungs and/or increased tissue water content. The hemoglobin content of lung, spleen, and kidney was also elevated in transgenic animals due to trapped hemoglobin and/or increased blood volume. When transgenic and control mice were examined by magnetic resonance imaging at 9.4 tesla, some transgenic animals had enlarged kidneys with prolonged relaxation time, consistent with increased organ weight and water content. The glomerular filtration rate was elevated in transgenic animals, which is characteristic of young sickle cell patients. Furthermore, exposure to hypoxia resulted in significantly decreased hematocrit, increased erythrocyte density, and induced a urine-concentrating defect. We conclude that the transgenic mouse line reported here has chronic organ damage and further hematological and organ dysfunction can be induced by hypoxia.

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