Abstract

Amyloid beta (Aβ) aggregation and deposition is a key pathological hallmark of AD. Growing evidence suggests that neurotoxicity of this peptide is related to the formation of toxic oligomeric aggregates. Therefore, a deeply investigated therapeutic strategy comes at present from blocking the formation of these species to non-toxic aggregates. Among other considered strategies, the multi-target approach has been proposed as a more suitable potential therapy, precisely due to the multifactorial nature of AD. In this context, we recently identified ASS234, a novel compound that possesses a significant multipotent profile since it is able to inhibit cholinesterase and monoamine oxidase enzymes as well as to interfere in Aβ aggregation process. In this work, we investigated more in detail the effects of ASS234 on Aβ aggregation and toxicity in vitro as well as we explored its ability to penetrate to the CNS. We report that ASS234 inhibited Aβ_1-42 self-aggregation more efficiently than that of Aβ_1-40, limiting the formation of fibrillar and oligomeric species. Additionally, ASS234 completely blocked the aggregation mediated by AChE of both Aβ_1-42 and Aβ_1-40, showing a dual binding site to AChE. Interestingly, ASS234 significantly reduced Aβ_1-42-mediated toxicity in SH-SY5Y human neuroblastoma cells through the prevention of the mitochondrial apoptosis pathway activation. Also importantly, we observed a significant ability of ASS234 to capture free-radical species in vitro as well as a potent effect in preventing the Aβ_1-42-induced depletion of antioxidant enzymes (catalase and SOD-1). Finally, we report the capability of ASS234 to cross the bloodbrain barrier. Overall, our in vitro results show that ASS234 may have an impact on different processes involved in AD pathogenesis and provide evidences that it has encouraging attributes as a therapeutic lead compound.

Keywords: Alzheimer’s disease therapy, amyloid β, cholinesterase inhibitors, multi-target directed ligand, neuroprotection, propargylamine.