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Oxysterol-induced rearrangement of the liquid-ordered phase: a possible link to Alzheimer's disease?

ABSTRACT: Nearest-neighbor recognition measurements have been made for an exchangeable phospholipid (A) interacting with an exchangeable form of cholesterol (B) in host membranes derived from 1, 2-dipalmitoyl-sn-glycero-3-phosphocholine and varying concentrations of cholesterol, 7beta-hydroxycholesterol (7beta-OH), and 25-hydroxycholesterol (25-OH). Whereas partial replacement of cholesterol with 7beta-OH strengthens the association between A and B, a similar substitution with 25-OH weakens this association. A model that accounts for this dichotomy, and the possible relevance of these findings to the cytotoxicity of 7beta-OH and to Alzheimer's disease are briefly discussed.

SUBMITTER: Mitomo H

PROVIDER: S-EPMC2748238 | biostudies-other | 2009 Sep

REPOSITORIES: biostudies-other

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Oxysterol-induced rearrangement of the liquid-ordered phase: a possible link to Alzheimer's disease?

Mitomo Hideyuki H Chen Wen-Hua WH Regen Steven L SL

Journal of the American Chemical Society 20090901 34

Nearest-neighbor recognition measurements have been made for an exchangeable phospholipid (A) interacting with an exchangeable form of cholesterol (B) in host membranes derived from 1, 2-dipalmitoyl-sn-glycero-3-phosphocholine and varying concentrations of cholesterol, 7beta-hydroxycholesterol (7beta-OH), and 25-hydroxycholesterol (25-OH). Whereas partial replacement of cholesterol with 7beta-OH strengthens the association between A and B, a similar substitution with 25-OH weakens this associati ...[more]

PMID: 19658396

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