Graphene Quantum Dots Attenuate TDP-43 Proteinopathy in Amyotrophic Lateral Sclerosis

Abstract

Aberrant phase separation- and stress granule (SG)-mediated cytosolic aggregation of TDP-43 in motor neurons is the hallmark of amyotrophic lateral sclerosis (ALS). In this study, we found that graphene quantum dots (GQDs) potentially modulate TDP-43 aggregation during SG dynamics and phase separation. The intrinsically disordered region in the C-terminus of TDP-43 exhibited amyloid fibril formation; however, GQDs inhibited the formation of amyloid fibrils through direct intermolecular interactions with TDP-43. These effects were accompanied by attenuation of the ALS phenotype in animal models. Additionally, GQDs delayed the onset and survival of TDP-43 transgenic mouse models by enhancing motor neuron survival, reducing glial activation, and reducing the cytosolic aggregation of TDP-43 in motor neurons. In this research, we demonstrated the efficacy of GQDs on the SG-mediated aggregation of TDP-43 and the binding property of GQDs with TDP-43. Additionally, we demonstrated the clinical feasibility of GQDs using several animal models and other types of ALS caused by FUS and C9orf72. Therefore, GQDs could offer a new therapeutic approach for proteinopathy-associated ALS.