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Anionic Oligothiophenes Compete for Binding of X-34 but not PIB to Recombinant A? Amyloid Fibrils and Alzheimer's Disease Brain-Derived A?.

ABSTRACT: Deposits comprised of amyloid-? (A?) are one of the pathological hallmarks of Alzheimer's disease (AD) and small hydrophobic ligands targeting these aggregated species are used clinically for the diagnosis of AD. Herein, we observed that anionic oligothiophenes efficiently displaced X-34, a Congo Red analogue, but not Pittsburgh compound?B (PIB) from recombinant A? amyloid fibrils and Alzheimer's disease brain-derived A?. Overall, we foresee that the oligothiophene scaffold offers the possibility to develop novel high-affinity ligands for A? pathology only found in human AD brain, targeting a different site than PIB.

SUBMITTER: Back M

PROVIDER: S-EPMC5215536 | biostudies-other | 2016 Dec

REPOSITORIES: biostudies-other

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Anionic Oligothiophenes Compete for Binding of X-34 but not PIB to Recombinant Aβ Amyloid Fibrils and Alzheimer's Disease Brain-Derived Aβ.

Bäck Marcus M Appelqvist Hanna H LeVine Harry H Nilsson K Peter R KP

Chemistry (Weinheim an der Bergstrasse, Germany) 20161103 51

Deposits comprised of amyloid-β (Aβ) are one of the pathological hallmarks of Alzheimer's disease (AD) and small hydrophobic ligands targeting these aggregated species are used clinically for the diagnosis of AD. Herein, we observed that anionic oligothiophenes efficiently displaced X-34, a Congo Red analogue, but not Pittsburgh compound B (PIB) from recombinant Aβ amyloid fibrils and Alzheimer's disease brain-derived Aβ. Overall, we foresee that the oligothiophene scaffold offers the possibilit ...[more]

PMID: 27767229

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