The antidepressant drug; trazodone inhibits Tau amyloidogenesis: Prospects for prophylaxis and treatment of AD

Tau protein, characterized as "natively unfolded", is involved in microtubule assembly/stabilization in physiological conditions. Under pathological conditions, Tau dysfunction leads to its accumulation of insoluble toxic amyloid aggregates and thought to be involved in the degeneration and neuronal death associated with neurodegenerative diseases. Trazodone (TRZ), a triazolopyridine derivative, is a selective serotonin reuptake inhibitor (SSRI) which increases serotonin levels in synaptic cleft and potentiating serotonin activity, with antidepressant and sedative properties. This drug is more effective and tolerable than other therapeutic agents. In this study, the 1N4R isoform of Tau protein was purified and the effect of TRZ on the protein fibrillation was investigated using multi-spectroscopic techniques as well as computational methods. The results showed that TRZ is not only able to affect formation of Tau amyloid fibrils in vitro but also attenuates Tau oligomerization within SH-SY5Y cell line resulting in more cells surviving. Moreover, membrane disrupting activity of Tau aggregates decreased upon TRZ treatment. The binding forces involved in TRZ-Tau interaction were also explored using both experimental as well as theoretical docking/molecular dynamics approaches. The results of the current work may open new insights for applying therapeutic potential of TRZ against Alzheimer's disease.