Details

Autor(en) / Beteiligte

• Schumann-Gillett, Alexandra
• O'Mara, Megan L.

Titel

The effects of oxidised phospholipids and cholesterol on the biophysical properties of POPC bilayers

Ist Teil von

• Biochimica et biophysica acta. Biomembranes, 2019-01, Vol.1861 (1), p.210-219

Ort / Verlag

Netherlands: Elsevier B.V

Erscheinungsjahr

2019

Link zum Volltext

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• Oxidation of unsaturated membrane phospholipids by oxidative stress is associated with inflammation, infection, numerous diseases and neurodegenerative disorders. Lipid oxidation is observed in experimental samples when the parent lipid is exposed to oxidative stressors. The effect of phospholipid oxidation on the properties of biological membranes are still being explored, while low concentrations (0.1–2.0 mol%) of oxidised phospholipids are associated with disease states [1]. Previous computational studies have focused on the effect of high concentrations (~50 mol%) of oxidised phospholipids on binary lipid bilayers. This work systematically characterises the effect of lower concentrations (~10 mol%) of two oxidised lipid species, PoxnoPC (1-palmitoyl-2-(9′-oxo-nonanoyl)-sn-glycero-3-phosphocholine) or PazePC (1-palmitoyl-2-azelaoyl-sn-glycero-3-phosphocholine), on POPC/cholesterol and pure POPC bilayers. During μs atomistic simulations in pure POPC bilayers, PoxnoPC and PazePC reoriented their oxidised sn-2 acyl chains towards the solution, and PazePC adopted an extended conformation. The addition of 20 mol% cholesterol not only modulated the fluidity of the bilayers; it also modulated the flexibility of the PoxnoPC oxidised sn-2 tail, reducing bilayer disorder. In contrast, the addition of cholesterol had little effect on bilayers containing PazePC. Our studies show that the effect of oxidised lipids on the biophysical properties of a multicomponent bilayer cannot be intuitively extrapolated from a binary lipid system. [Display omitted] •Oxidised membrane lipids are being increasingly associated with disease.•Oxidised phospholipids affect biophysical properties of lipid bilayers.•Oxidised lipid species extend portions out of bilayer and into solution.•Cholesterol modulates bilayer fluidity; degree of extension out of bilayer.•Important to consider oxidised lipids in bilayer studies; non-trivial behaviour.