MAPT and type 2 diabetes mellitus: Thus, T2DM may be a significant risk factor for development of neurodegenerative pathologies by the alteration of brain metabolism and protein turnover, activation/inactivation of signaling pathways that may result in elevating level of peptides and proteins prone to aggregation, such as Aβ and α-Syn, or their PTM, such as phosphorylation of tau, dramatically affecting their aggregation capacity.