title: Molecular dynamic simulation study of cholesterol and conjugated double bonds in lipid bilayers.
abstract: Conjugated linoleic acids (CLA) are found naturally in dairy products. Two isomers of CLA, that differ only in the location of cis and trans double bonds, are found to have distinct and different biological effects. The cis 9 trans 11 (C9T11) isomer is believed to have anti-carcinogenic effects, while the trans 10 cis 12 (T10C12) isomer is believed to be associated with anti-obesity effects. In this paper we extend earlier molecular dynamics (MD) simulations of pure CLA-phosphatidylcholine bilayers to investigate the comparative effects of cholesterol on bilayers composed of the two respective isomers. Simulations of phosphatidylcholine lipid bilayers in which the sn-2 chains contained one of the two isomers of CLA were performed in which, for each isomer, the simulated bilayers contained 10% and 30% cholesterol (Chol). From MD trajectories we calculate and compare structural properties of the bilayers, including areas per molecule, thickness of bilayers, tilt angle of cholesterols, order parameter profiles, and one and two-dimensional radial distribution function (RDF), as functions of Chol concentration. While the structural effect of cholesterol is approximately the same for both isomers, we find differences at an atomistic level in order parameter profiles and in two-dimensional radial distribution functions.
authors: Institute of Medical Genetics, Shanghai Children's Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors: Guijun
authors: G
authors: Zhao
authors: P V
authors: PV
authors: Subbaiah
authors: Evan
authors: E
authors: Mintzer
authors: See-Wing
authors: SW
authors: Chiu
authors: Eric
authors: E
authors: Jakobsson
authors: H L
authors: HL
authors: Scott
mesh_terms: D002784:Cholesterol / Q000737:chemistry*; D003198:Computer Simulation; D044243:Linoleic Acids, Conjugated / Q000737:chemistry; D008051:Lipid Bilayers / Q000737:chemistry*; D056004:Molecular Dynamics Simulation
chemical_list: D044243:Linoleic Acids, Conjugated; D008051:Lipid Bilayers; D002784:Cholesterol