Carriers of ataxia-telangiectasia gene display additional protein fraction and changes in the environment of SH groups in erythrocyte membrane

One of many risk factors for cardiovascular disease appears to be oxidative stress. To estimate possible changes in redox balance, membrane fluidity, and cholesterol level in erythrocytes was collected erythrocytes from patients diagnosed with coronary artery disease (CAD). The study included 20 patients with previous myocardial infarction occurring more than 6 months prior to the time of screening with low-density lipoprotein cholesterol (LDL-C) >70 mg/dL and 21 healthy controls. The following parameters were studied: catalase, glutathione peroxidase (GPx), superoxide dismutase (SOD), thiobarbituric acid reactive substrates (TBARS), sulfhydryl (SH) groups in membrane protein, total cholesterol level, and erythrocyte membrane fluidity. Our study showed an increase in the level of lipid peroxidation (13%) and total cholesterol (19%), and a decrease in membrane fluidity (14%) in the subsurface layers and in the deeper layers of erythrocyte membrane (7%) isolated from patients with CAD in comparison to healthy controls. A significant decrease in catalase (10%) and SOD (17%) activities were also observed. No changes in GPx activity or the level of SH groups were observed. Our study indicates that there are disorders in the antioxidant system as well as changes in the membrane structure of erythrocytes obtained from CAD patients.

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The Effect of Highly Hydroxylated Fullerenol C60(OH)36on Human Erythrocyte Membrane Organization

Journal of Spectroscopy ◽

10.1155/2015/825914 ◽

2015 ◽

Vol 2015 ◽

pp. 1-6 ◽

Cited By ~ 2

Author(s):

Jacek Grebowski ◽

Anita Krokosz

Keyword(s):

Membrane Proteins ◽

Membrane Fluidity ◽

Erythrocyte Membrane ◽

Conformational Changes ◽

Protein Interactions ◽

Erythrocyte Membranes ◽

Resonance Spectroscopy ◽

Protein Protein Interactions ◽

Hydrophobic Region ◽

Sh Groups

The mechanism of the interaction of highly hydroxylated fullerenol C60(OH)36with erythrocyte membranes was studied by electron spin resonance spectroscopy (ESR) of stearic acid derivatives labeled with a nitroxyl radical at C-12 or C-16 and with a nitroxyl derivative of maleimide covalently attached to sulfhydryl groups of membrane proteins. A significant increase in membrane fluidity in the hydrophobic region of the lipid bilayer was observed for 12-doxylstearic acid at fullerenol concentrations of 100 mg/L or 150 mg/L, while for 16-doxylstearic acid significant increase in fluidity was only observed at 150 mg/L. Fullerenol at 100 mg/L or 150 mg/L caused conformational changes in membrane proteins, expressed as an increase in thehw/hsparameter, when fullerenol was added before the maleimide spin label (MSL) to the membrane suspension. The increase of thehw/hsparameter may be caused by changes in lipid-protein or protein-protein interactions which increase the mobility of the MSL label and as a result increase the membrane fluidity. Incubation of the membranes with the MSL before the addition of fullerenol blocked the available membrane protein –SH groups and minimized the interaction of fullerenol with them. This confirms that fullerenol interacts with erythrocyte membrane proteins via available protein –SH groups.

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Involvement of cytoskeletal proteins in the barrier function of the human erythrocyte membrane. I. Impairment of resealing and formation of aqueous pores in the ghost membrane after modification of SH groups

Biochimica et Biophysica Acta (BBA) - Biomembranes ◽

10.1016/0005-2736(92)90230-j ◽

1992 ◽

Vol 1106 (1) ◽

pp. 126-136 ◽

Cited By ~ 10

Author(s):

Sabine Klonk ◽

Bernhard Deuticke

Keyword(s):

Erythrocyte Membrane ◽

Human Erythrocyte ◽

Barrier Function ◽

Cytoskeletal Proteins ◽

Human Erythrocyte Membrane ◽

Sh Groups

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Cross-linking of SH-groups in the erythrocyte membrane enhances transbilayer reorientation of phospholipids. Evidence for a limited access of phospholipids to the reorientation sites

Biochimica et Biophysica Acta (BBA) - Biomembranes ◽

10.1016/0005-2736(84)90322-5 ◽

1984 ◽

Vol 769 (2) ◽

pp. 390-398 ◽

Cited By ~ 61

Author(s):

W.L. Bergmann ◽

V. Dressler ◽

C.W.M. Haest ◽

B. Deuticke

Keyword(s):

Erythrocyte Membrane ◽

Cross Linking ◽

Limited Access ◽

Sh Groups

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Observation of Concanavalin-A receptors on hydrated planar erythrocyte membrane film by in situ electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100076640 ◽

1983 ◽

Vol 41 ◽

pp. 608-609

Author(s):

Neng-Bo He ◽

S.W. Hui

Keyword(s):

Lipid Bilayers ◽

Erythrocyte Membrane ◽

Lipid Membranes ◽

Surface Film ◽

Biological Membranes ◽

Electron Microscopic Observation ◽

Electron Microscopic ◽

Black Lipid Membranes ◽

Fine Mesh ◽

Planar Films

Monolayers and planar "black" lipid membranes have been widely used as models for studying the structure and properties of biological membranes. Because of the lack of a suitable method to prepare these membranes for electron microscopic observation, their ultrastructure is so far not well understood. A method of forming molecular bilayers over the holes of fine mesh grids was developed by Hui et al. to study hydrated and unsupported lipid bilayers by electron diffraction, and to image phase separated domains by diffraction contrast. We now adapted the method of Pattus et al. of spreading biological membranes vesicles on the air-water interfaces to reconstitute biological membranes into unsupported planar films for electron microscopic study. hemoglobin-free human erythrocyte membrane stroma was prepared by hemolysis. The membranes were spreaded at 20°C on balanced salt solution in a Langmuir trough until a surface pressure of 20 dyne/cm was reached. The surface film was repeatedly washed by passing to adjacent troughs over shallow partitions (fig. 1).

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