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Updated: Jul 14, 2026
09:38
Biomembrane Fabrication by the Solvent-assisted Lipid Bilayer (SALB) Method
Published on: December 1, 2015
Control of lipid membrane stability by cholesterol content
1Institut de Pharmacologie et de Biologie Structurale du CNRS, UPR 9062, F-31062 Toulouse Cedex, France.
Biophysical Journal
|March 30, 1999
Summary
Cholesterol concentration impacts lipid bilayer organization and permeability, especially in the gel state. Higher cholesterol levels facilitate membrane permeabilization and protein insertion under milder electric fields.
Area of Science:
- Biophysics
- Membrane Biology
- Materials Science
Background:
- Cholesterol is a key regulator of cell membrane organization and function.
- Lipid bilayer permeability is crucial for cellular processes.
- Understanding cholesterol's role in membrane properties is essential for various biological and medical applications.
Purpose of the Study:
- To systematically investigate the concentration-dependent effect of cholesterol on lipid bilayer permeability.
- To explore how cholesterol influences membrane organization and electropermeabilization in different lipid states (gel and fluid).
- To determine the impact of cholesterol on electroinsertion of membrane proteins.
Main Methods:
- Utilized electropermeabilization of lipid vesicles induced by external electric fields.
- Measured transmembrane potential difference modulation to assess membrane electrical permeability.
- Studied cholesterol effects on phosphatidylcholine bilayers in both gel and fluid states.
- Investigated cholesterol's influence on electroinsertion of solubilized membrane proteins.
Main Results:
- Cholesterol did not affect electropermeabilization or electroinsertion in fluid-state lipids.
- In gel-state lipids, cholesterol exhibited a dose-dependent effect on membrane properties.
- At 6% cholesterol, electropermeabilization and electroinsertion were inhibited.
- Above 12% cholesterol, electropermeabilization and electroinsertion occurred under milder electric field conditions.
- These effects are tentatively attributed to cholesterol-induced alterations in the bilayer's hydrophobic core.
Conclusions:
- Lipid membrane permeability is significantly affected by cholesterol content, particularly in the gel state.
- Cholesterol's influence on membrane organization and permeability is state-dependent (gel vs. fluid).
- The study provides insights into cholesterol's role in modulating membrane electrical properties and protein handling.
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