22 Sep 2009, 4:20 AM
A
growing body of experimental evidence indicates that the interaction between
amyloid

peptide and lipid bilayer membranes plays an important
role in the development of Alzheimer disease. Recent experimental evidence
also suggests that trehalose, a simple disaccharide, reduces the toxicity
of amyloid

peptide. Molecular simulations are used to examine
the effect of trehalose
on the conformational stability of amyloid

peptide in aqueous solution and its effect on the
interaction between amyloid

peptide and a model phospholipid bilayer
membrane. It is found that, in aqueous solution, the peptide
exhibits a random coil conformation but, in the presence of
trehalose, it adopts an alpha helical conformation. It is then
shown that the insertion of amyloid

peptide into a
membrane is more favorable when the peptide is folded into
an

-helix than in a random coil conformation, thereby suggesting
that trehalose promotes the insertion of

-helical amyloid

into
biological membranes.
©2009
American Institute of Physics
Trehalose and Alzhiemers