Relationship between lipid peroxidation and rigidity in L-alpha-phosphatidylcholine-DPPC vesicles
M A Soto-Arriaza1, C P Sotomayor, E A Lissi
1Departamento de Química Física, Facultad de Química, Pontificia Universidad Católica de Chile, Casilla 306, Santiago 6094411, Chile. marcosoto@uc.cl
Journal of Colloid and Interface Science
|May 13, 2008
Summary
Adding dipalmitoylphosphatidylcholine (DPPC) to egg-phosphatidylcholine (egg-PC) vesicles enhances lipid bilayer stability, reducing oxidation and water permeability. These physical changes in the lipid bilayer contribute to a lower oxidation rate.
Area of Science:
- Biochemistry
- Physical Chemistry
- Materials Science
Background:
- Unsaturated lipids in vesicles are prone to oxidation.
- Understanding lipid bilayer physical properties is crucial for stability.
Purpose of the Study:
- To investigate how dipalmitoylphosphatidylcholine (DPPC) incorporation affects egg-phosphatidylcholine (egg-PC) vesicle properties.
- To correlate physical changes with oxidation rates and water permeability.
Main Methods:
- Utilized fluorescence anisotropy (DPH) and generalized polarization (laurdan) to probe lipid bilayer physical properties.
- Measured water efflux under hypertonic shock.
- Assessed oxidation rates via oxygen uptake and malondialdehyde (MDA) formation.
Main Results:
- DPPC incorporation decreased alkyl chain mobility and increased bilayer interface rigidity.
- DPPC addition reduced water efflux rate.
- Oxidation induced similar rigidification and reduced water permeability, suggesting a link between physical state and stability.
Conclusions:
- DPPC incorporation into egg-PC vesicles enhances bilayer stability by increasing rigidity.
- The observed physical changes correlate with reduced oxidation rates and water permeation.
- Lipid bilayer physical properties significantly influence vesicle stability and susceptibility to oxidation.
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