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Berntsson, E.

Publications and source records attributed to Berntsson, E..

2 recordsLinked to original sources

Lithium ions display weak interaction with amyloid-beta (Aβ) peptides and have minor effects on their aggregation

Alzheimers disease (AD) is an incurable disease and the main cause of age-related dementia worldwide, despite decades of research. Treatment of AD with lithium (Li) has showed promising results, but the underlying mechanism is unclear. The pathological hallmark of AD brains is deposition of amyloid plaques, consisting mainly of amyloid-{beta} (A{beta}) peptides aggregated into amyloid fibrils. The plaques contain also metal ions of e.g. Cu, Fe, and Zn, and such ions are known to interact with A{beta} peptides and modulate their aggregation and toxicity. The interactions between A{beta} peptides and Li+ ions have however not been well investigated. Here, we use a range of biophysical techniques to characterize in vitro interactions between A{beta} peptides and Li+ ions. We show that Li+ ions display weak and non-specific interactions with A{beta} peptides, and have minor effects on A{beta} aggregation. These results indicate that possible beneficial effects of Li on AD pathology are not likely caused by direct interactions between A{beta} peptides and Li+ ions.

biochemistry↗

6-gingerol interferes with amyloid-beta (Aβ) peptide aggregation

Alzheimers disease (AD) is the most prevalent age-related cause of dementia. AD affects millions of people worldwide, and to date there is no cure. The pathological hallmark of AD brains is deposition of amyloid plaques, which mainly consist of amyloid-{beta} (A{beta}) peptides, commonly 40 or 42 residues long, that have aggregated into amyloid fibrils. Intermediate aggregates in the form of soluble A{beta} oligomers appear to be highly neurotoxic. Cell and animal studies have previously demonstrated positive effects of the molecule 6-gingerol on AD pathology. Gingerols are the main active constituents of the ginger root, which in many cultures is a traditional nutritional supplement for memory enhancement. Here, we use biophysical experiments to characterize in vitro interactions between 6-gingerol and A{beta}40 peptides. Our experiments with atomic force microscopy imaging, and nuclear magnetic resonance and Thioflavin-T fluorescence spectroscopy, show that the hydrophobic 6-gingerol molecule interferes with formation of A{beta}40 aggregates, but does not interact with A{beta}40 monomers. Thus, together with its favourable toxicity profile, 6-gingerol appears to display many of the desired properties of an anti-AD compound.

biochemistry↗