Abstract
Although the glycation of Tau that is involved in paired helical filament formation in Alzheimer's disease has been widely studied, little attention has been paid to the role of D-ribose in the glycation of Tau. Here, we show that Tau is rapidly glycated in the presence of D-ribose, resulting in oligomerization and polymerization. Glycated derivatives appeared after 24 h incubation. Western blotting indicated the formation of advanced glycation end-products (AGEs) during initial stages of glycation. Thioflavin T-positive (ThT-positive) aggregations that appeared from day 4 indicated the globular-like features. Atomic force microscopy revealed that the surface morphology of ribosylated Tau40 was globular-like. Kinetic studies suggested that D-ribosylated Tau is slowly oligomerized and rapidly polymerized with ThT-positive features. Moreover, D-ribosylated Tau aggregates were highly toxic to SHSY5Y cells and resulted in both apoptosis and necrosis. This work has demonstrated that D-ribose reacted with Tau protein rapidly, producing ThT-positive aggregations which had high cytotoxicity.