Abstract:
:Formation of amyloid oligomers, the most toxic species of amyloids in degenerative diseases, is critically coupled to the interplay with surrounding water. The hydrophobic force driving the oligomerization causes water removal from interfaces, changing the surface-hydration properties. Here, we show that such effects alter the magnetic relaxation response of local water in ways that may enable oligomer detection. By using water proton magnetic resonance spectroscopy, we measured significantly longer transverse magnetic relaxation (T(2)) times in mixtures of serum and amyloidogenic Aβ(1-42) peptides versus similar concentration solutions of serum and nonamyloidogenic scrambled Aβ(42-1) peptides. Immunochemistry with oligomer-specific antibodies, electron microscopy and computer simulations demonstrated that the hyperintense magnetic signal correlates with Aβ(1-42) oligomerization. Finding early biophysical markers of the oligomerization process is crucial for guiding the development of new noninvasive imaging techniques, enabling timely diagnosis of amyloid-related diseases and pharmacological intervention.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Walton JH,Berry RS,Despa Fdoi
10.1016/j.bpj.2011.03.029subject
Has Abstractpub_date
2011-05-04 00:00:00pages
2302-8issue
9eissn
0006-3495issn
1542-0086pii
S0006-3495(11)00377-8journal_volume
100pub_type
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