Assessment of neurobehavioral and histopathological impacts of graphene quantum Dots in NMRI mice

Graphene quantum dots (GQDs) are attracting significant interest in biomedicine due to their unique properties. While most studies have focused on the general toxicity of GQDs, our understanding of their neurotoxicity remains limited. This study aims to elucidate the neurotoxic effects of GQDs using in vivo experimental models. Adult male NMRI mice were administered GQDs via gavage at doses of 10, 20, and 40 mg/kg for 30 days. Locomotor activity, anxiety-like behaviors, and learning and memory abilities were assessed using the open-field test, elevated-plus maze (EPM) test, and passive avoidance (PA) test, respectively. Oxidative stress markers in hippocampal tissue were analyzed, and histopathological alterations were evaluated. The results from behavioral tests, as well as histological and biochemical evaluations, demonstrated that low doses of GQDs significantly impaired memory function and increased anxiety. High doses of GQDs notably reduced motor activity. Additionally, there was an accumulation of malondialdehyde (MDA) and a reduction in catalase (CAT) activity in hippocampal tissue. Histopathological assessments revealed significant alterations in the hippocampal tissue of GQD-exposed mice. These findings indicate that 30-day exposure to GQDs results in behavioral disturbances and neuronal cell changes in mice.