title: Cholesterol under oxidative stress-How lipid membranes sense oxidation as cholesterol is being replaced by oxysterols.
abstract: The behavior of oxysterols in phospholipid membranes and their effects on membrane properties were investigated by means of dynamic light scattering, fluorescence spectroscopy, NMR, and extensive atomistic simulations. Two families of oxysterols were scrutinized-tail-oxidized sterols, which are mostly produced by enzymatic processes, and ring-oxidized sterols, formed mostly via reactions with free radicals. The former family of sterols was found to behave similar to cholesterol in terms of molecular orientation, roughly parallel to the bilayer normal, leading to increasing membrane stiffness and suppression of its membrane permeability. In contrast, ring-oxidized sterols behave quantitatively differently from cholesterol. They acquire tilted orientations and therefore disrupt the bilayer structure with potential implications for signaling and other biochemical processes in the membranes.
authors: Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland. Electronic address: waldemar.kulig@tut.fi.
authors: Waldemar
authors: W
authors: Kulig
authors: J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, v. v. i., Dolejskova 3, 18223 Prague 8, Czech Republic.
authors: Agnieszka
authors: A
authors: Olżyńska
authors: J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, v. v. i., Dolejskova 3, 18223 Prague 8, Czech Republic. Electronic address: piotr.jurkiewicz@jh-inst.cas.cz.
authors: Piotr
authors: P
authors: Jurkiewicz
authors: Department of Physics and Chemistry, University of Oulu, P.O. Box 3000, FI-90014 Oulu, Finland.
authors: Anu M
authors: AM
authors: Kantola
authors: Department of Physics and Chemistry, University of Oulu, P.O. Box 3000, FI-90014 Oulu, Finland.
authors: Sanna
authors: S
authors: Komulainen
authors: Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland.
authors: Moutusi
authors: M
authors: Manna
authors: Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland.
authors: Mohsen
authors: M
authors: Pourmousa
authors: Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland; Rudjer Bošković Institute, Division of Organic Chemistry and Biochemistry, POB 180, HR-10002 Zagreb, Croatia.
authors: Mario
authors: M
authors: Vazdar
authors: J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, v. v. i., Dolejskova 3, 18223 Prague 8, Czech Republic; Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 16610 Prague 6, Czech Republic. Electronic address: lukasz.cwiklik@uochb.cas.cz.
authors: Lukasz
authors: L
authors: Cwiklik
authors: Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland.
authors: Tomasz
authors: T
authors: Rog
authors: Weill Cornell Medical College, New York, NY 10065, USA.
authors: George
authors: G
authors: Khelashvili
authors: Institute of Chemistry and the Fritz Haber Research Center, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
authors: Daniel
authors: D
authors: Harries
authors: Department of Physics and Chemistry, University of Oulu, P.O. Box 3000, FI-90014 Oulu, Finland.
authors: Ville-Veikko
authors: VV
authors: Telkki
authors: J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, v. v. i., Dolejskova 3, 18223 Prague 8, Czech Republic.
authors: Martin
authors: M
authors: Hof
authors: Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland; MEMPHYS-Center for Biomembrane Physics, University of Southern Denmark, Odense, Denmark.
authors: Ilpo
authors: I
authors: Vattulainen
authors: Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 16610 Prague 6, Czech Republic; Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland.
authors: Pavel
authors: P
authors: Jungwirth
mesh_terms: D002462:Cell Membrane / Q000737:chemistry*; D005454:Fluorescence Polarization; D006888:Hydroxycholesterols / Q000737:chemistry*; D008051:Lipid Bilayers / Q000737:chemistry*; D056004:Molecular Dynamics Simulation; D018384:Oxidative Stress; D010713:Phosphatidylcholines / Q000737:chemistry
chemical_list: D006888:Hydroxycholesterols; D008051:Lipid Bilayers; D010713:Phosphatidylcholines; C028694:1-palmitoyl-2-oleoylphosphatidylcholine
keywords: DPH anisotropy; Laurdan fluorescence; Liposomes; Molecular dynamics simulations; NMR measurements; Oxysterols; Phospholipid bilayers; Tilt modulus