Control of Lipid Membrane Stability by Cholesterol Content

Cholesterol has a concentration-dependent effect on membrane organization. It is able to control the membrane permeability by inducing conformational ordering of the lipid chains. A systematic investigation of lipid bilayer permeability is described in the present work. It takes advantage of the tra...

Full description

Saved in:
Bibliographic Details
Published in:Biophysical journal 1999-04, Vol.76 (4), p.2072-2080
Main Authors: Raffy, Sophie, Teissié, Justin
Format: Article
Language:English
Subjects:
1,2-Dipalmitoylphosphatidylcholine - chemistry
Animals
Biophysical Phenomena
Biophysics
Cholesterol
Cholesterol - chemistry
Drug Stability
Glycophorin - chemistry
In Vitro Techniques
Lipid Bilayers - chemistry
Lipids
Liposomes - chemistry
Membrane Lipids - chemistry
Membranes
Models, Chemical
Permeability
Pharmacology
Phosphatidylcholines - chemistry
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Cholesterol has a concentration-dependent effect on membrane organization. It is able to control the membrane permeability by inducing conformational ordering of the lipid chains. A systematic investigation of lipid bilayer permeability is described in the present work. It takes advantage of the transmembrane potential difference modulation induced in vesicles when an external electric field is applied. The magnitude of this modulation is under the control of the membrane electrical permeability. When brought to a critical value by the external field, the membrane potential difference induces a new membrane organization. The membrane is then permeable and prone to solubilized membrane protein back-insertion. This is obtained for an external field strength, which depends on membrane native permeability. This approach was used to study the cholesterol effect on phosphatidylcholine bilayers. Studies have been performed with lipids in gel and in fluid states. When cholesterol is present, it does not affect electropermeabilization and electroinsertion in lipids in the fluid state. When lipids are in the gel state, cholesterol has a dose-dependent effect. When present at 6% (mol/mol), cholesterol prevents electropermeabilization and electroinsertion. When cholesterol is present at more than 12%, electropermeabilization and electroinsertion are obtained under milder field conditions. This is tentatively explained by a cholesterol-induced alteration of the hydrophobic barrier of the bilayer core. Our results indicate that lipid membrane permeability is affected by the cholesterol content.
ISSN:0006-3495
1542-0086
DOI:10.1016/S0006-3495(99)77363-7