Amyloid plaques, deposits of beta-amyloid (Aβ42) peptide, is a hallmark of Alzheimer’s disease (AD). These plaques are generated by the self-assembling of Aβ42 monomers into supramolecular nanofibrillar structures stabilized by the peptide’s β-sheets. For several years these plaques have been considered the basis of cell toxicity that lead to neuronal cell death in AD. However, recent studies suggest that the neurotoxic effect are derived from the smaller Aβ42 protein aggregates, i.e. oligomers [1, 2].
We have been study natural polyphenols (e.g. vescalagin and castalagin). We proved their capacity to rescue cell viability affected by the cytotoxicity of Aβ42 fibrils. In fact, natural compounds, such as the use of Epigallocatechin gallate (EGCG) as been proposed as modulators of Aβ42 fibre formation, since their ability to block the Aβ42 self-assembly process has been reported . The activity of EGCG is reported to occur through the interference of the Pi-Pi stacking within the Aβ42 supramolecular arrangement . In general, most of the natural polyphenols reported to modulate Aβ42 self-assembly present galloyl-type moieties. Based on this observation, and with our own results from vescalagin/castalagin, we designed dendrimers displaying this type of moiety (Gallic Acid – GA) on their surface and tested them for their ability to modulate Aβ42 fibrillization.