Comparison of photodynamic efficiency of cholesterol, selected cholesterol esters, metabolites and oxidation products on lipid peroxidation processes

Cholesterol (Ch) is one of the most important components of biological membranes, which has a significant impact on their biophysical properties. As a key component of lipid membranes, Ch along with other unsaturated lipids present in a biological membrane undergoes oxidation reaction during oxidative stress. Cholesterol oxidation products, cholesteryl esters and metabolites are also localise in lipid membranes, where they may modify membrane properties. In this work the impact of cholesterol, selected cholesteryl esters, cholesterol oxidation products and metabolites on lipid peroxidation induced by photodynamic action has been studied using EPR oximetry and direct detection of singlet oxygen phosphorescence at 1270 nm. The obtained rate constants values of interaction of selected lipids and sterols with singlet oxygen indicate that the tested compounds are not efficient singlet oxygen quenchers. Nevertheless, the presence of sterols modifies to different extend the oxygen photoconsumption rate in peroxidisable liposomes.

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Physical effects of biologically formed cholesterol oxidation products on lipid membranes investigated with fluorescence depolarization spectroscopy and electron spin resonance.

The Journal of Lipid Research ◽

10.1016/s0022-2275(20)39133-1 ◽

1996 ◽

Vol 37 (7) ◽

pp. 1488-1502

Author(s):

J C Verhagen ◽

P ter Braake ◽

J Teunissen ◽

G van Ginkel ◽

A Sevanian

Keyword(s):

Electron Spin Resonance ◽

Electron Spin ◽

Lipid Membranes ◽

Oxidation Products ◽

Cholesterol Oxidation ◽

Fluorescence Depolarization ◽

Cholesterol Oxidation Products ◽

Spin Resonance ◽

Physical Effects

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Effect of dietary cholesterol oxidation products on the plasma clearance of chylomicrons in the rat

Lipids ◽

10.1007/s11745-002-0917-z ◽

2002 ◽

Vol 37 (5) ◽

pp. 455-462 ◽

Cited By ~ 6

Author(s):

D. F. Vine ◽

K. D. Croft ◽

L. J. Beilin ◽

J. C. L. Mamo

Keyword(s):

Plasma Clearance ◽

Dietary Cholesterol ◽

Oxidation Products ◽

Cholesterol Oxidation ◽

Cholesterol Oxidation Products

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Ezetimibe Impairs Uptake of Dietary Cholesterol Oxidation Products and Reduces Alterations in Hepatic Cholesterol Metabolism and Antioxidant Function in Rats

Lipids ◽

10.1007/s11745-013-3790-6 ◽

2013 ◽

Vol 48 (6) ◽

pp. 587-595 ◽

Cited By ~ 7

Author(s):

Shoichiro Terunuma ◽

Noriko Kumata ◽

Kyoichi Osada

Keyword(s):

Cholesterol Metabolism ◽

Dietary Cholesterol ◽

Oxidation Products ◽

Cholesterol Oxidation ◽

Hepatic Cholesterol ◽

Cholesterol Oxidation Products ◽

Antioxidant Function

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The Structural Integrity of the Model Lipid Membrane during Induced Lipid Peroxidation: The Role of Flavonols in the Inhibition of Lipid Peroxidation

Antioxidants ◽

10.3390/antiox9050430 ◽

2020 ◽

Vol 9 (5) ◽

pp. 430 ◽

Cited By ~ 2

Author(s):

Anja Sadžak ◽

Janez Mravljak ◽

Nadica Maltar-Strmečki ◽

Zoran Arsov ◽

Goran Baranović ◽

...

Keyword(s):

Lipid Peroxidation ◽

Lipid Bilayers ◽

Lipid Membranes ◽

Structural Changes ◽

Structural Integrity ◽

Lipid Membrane ◽

Membrane Properties ◽

Structural Reorganization ◽

Unsaturated Lipids ◽

Oxidative Attack

The structural integrity, elasticity, and fluidity of lipid membranes are critical for cellular activities such as communication between cells, exocytosis, and endocytosis. Unsaturated lipids, the main components of biological membranes, are particularly susceptible to the oxidative attack of reactive oxygen species. The peroxidation of unsaturated lipids, in our case 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), induces the structural reorganization of the membrane. We have employed a multi-technique approach to analyze typical properties of lipid bilayers, i.e., roughness, thickness, elasticity, and fluidity. We compared the alteration of the membrane properties upon initiated lipid peroxidation and examined the ability of flavonols, namely quercetin (QUE), myricetin (MCE), and myricitrin (MCI) at different molar fractions, to inhibit this change. Using Mass Spectrometry (MS) and Fourier Transform Infrared Spectroscopy (FTIR), we identified various carbonyl products and examined the extent of the reaction. From Atomic Force Microscopy (AFM), Force Spectroscopy (FS), Small Angle X-Ray Scattering (SAXS), and Electron Paramagnetic Resonance (EPR) experiments, we concluded that the membranes with inserted flavonols exhibit resistance against the structural changes induced by the oxidative attack, which is a finding with multiple biological implications. Our approach reveals the interplay between the flavonol molecular structure and the crucial membrane properties under oxidative attack and provides insight into the pathophysiology of cellular oxidative injury.

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