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Updated: Jul 12, 2025
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Cell-free Biochemical Fluorometric Enzymatic Assay for High-throughput Measurement of Lipid Peroxidation in High Density Lipoprotein
Published on: October 12, 2017
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Two separate mechanisms are involved in membrane permeabilization during lipid oxidation
Min Xie1, Eveline H W Koch1, Cornelis A van Walree2
1Membrane Biochemistry & Biophysics, Bijvoet Center for Biomolecular Research, Department of Chemistry, Utrecht University, Utrecht, the Netherlands.
Biophysical Journal
|October 31, 2023
Summary
Lipid oxidation damages cell membranes through two mechanisms: rapid permeabilization by truncated oxidized phospholipids and slower damage dependent on lipid unsaturation. Polyunsaturated lipids in mammalian membranes may promote long-term oxidative damage.
Area of Science:
- Biophysics
- Cell Biology
- Oxidative Stress
Background:
- Lipid oxidation is a key process in oxidative stress, altering cell membrane properties and function.
- The relationship between oxidative damage and membrane biophysical properties remains unclear.
- Reactive oxygen and nitrogen species (RONS) induce lipid oxidation in various pathophysiological conditions.
Purpose of the Study:
- To quantify lipid oxidation and determine biophysical membrane parameters.
- To investigate the mechanisms of membrane permeabilization induced by RONS.
- To explore the role of lipid unsaturation in oxidative membrane damage.
Main Methods:
- Utilized model membranes with varying lipid unsaturation.
- Employed cold plasma as a source of RONS.
- Quantified lipid oxidation and measured biophysical membrane parameters.
Main Results:
- Identified two distinct lipid oxidation-induced membrane permeabilization mechanisms.
- The first mechanism, independent of lipid unsaturation, involves truncated oxidized phospholipids and short-lived RONS.
- The second mechanism, dependent on lipid unsaturation, occurs after longer incubation and involves lipid oxygen adducts.
Conclusions:
- Oxidative damage to membranes is complex and context-dependent.
- Polyunsaturated lipids in mammalian membranes do not increase immediate RONS sensitivity but may contribute to long-term damage.
- Oxidized lipids released from membranes may act as signaling molecules.
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