The role of positively charged small biomolecules in the aggregation of hyperphosphorylated tau in Alzheimer’s disease

Tau proteins have recently drawn attention as a possible cause of Alzheimer’s disease (AD)-associated neuronal dementia. Hyperphosphorylated tau proteins detach from microtubules, impairing their stability and leading to neuronal degeneration. The present study focuses on understanding the molecular mechanisms behind the aggregation of hyperphosphorylated tau. Since hyperphosphorylated proteins are highly negatively charged, it is implausible that they create the damaging aggregates in the absence of some counteracting positive charge. This study found such an electrostatic (charge-charge) interaction between tau proteins and polyamines, identifying this interaction as crucial to promoting tau aggregation. In this study, we also directly observed the transition over time from tau protein aggregates to fibril structures. These findings challenge existing theories and offer insights into potential therapeutic targets for AD.