Oxysterol-induced rearrangement of the liquid-ordered phase: a possible link to Alzheimer's disease?
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.
Mitomo
Hideyuki
H
Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, USA.
Chen
Wen-Hua
WH
Regen
Steven L
SL
D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry / Q000378:metabolism; D000544:Alzheimer Disease / Q000378:metabolism / Q000473:pathology; D006888:Hydroxycholesterols / Q000737:chemistry* / Q000378:metabolism / Q000633:toxicity; D009682:Magnetic Resonance Spectroscopy; D021962:Membrane Microdomains / Q000187:drug effects / Q000378:metabolism; D008954:Models, Biological; D008956:Models, Chemical; D013696:Temperature
D006888:Hydroxycholesterols; D015060:1,2-Dipalmitoylphosphatidylcholine; C011724:cholest-5-en-3 beta,7 alpha-diol; C007997:25-hydroxycholesterol