(168d) Graphene Quantum Dots Prevent the Amyloidogenic Tau Protein Aggregation in Alzheimer’s Disease

Alzheimer’s disease (AD) and neurodegenerative tauopathies can lead to cognitive dysfunction. These diseases are strongly associated with the pathological aggregation of tau proteins into neurofibrillary tangles. Several redox-active aromatic compounds have been shown to inhibit tau aggregation. However, their inability to target specifically and cross the blood-brain barrier (BBB) could cause many difficulties in therapeutic use. Recently, it has been reported that graphene quantum dots (GQDs) can penetrate the BBB and can be easily functionalized for targeted delivery. Here we investigated the interactions of carboxylated and ʟ-/ᴅ-cysteine functionalized GQDs with tau proteins. Using Thioflavin T assay, transmission electron microscopy, and Fourier-transform infrared spectroscopy, we found that both types of GQDs not only inhibit the formation of tau fibril but also disaggregate tau filaments. Compared to previously reported redox-active aromatic compounds, rhodanine derivatives, GQDs with a concentration of 2 μM can achieve the same inhibitory effect as rhodanine derivatives with a concentration of 10 μM. Overall, our studies indicate that GQDs are promising candidates for therapeutics of tau pathology in AD and tauopathies.