Rare-earth nanoparticles induce depression, anxiety-like behavior, and memory impairment in mice

Rare-earth nanoparticles have been widely studied for disease diagnosis, in vivo optical imaging, biosensing, and drug delivery. However, the effects of rare-earth nanoparticles on a central nervous system remain unclear. Here, we report that the continuous exposure to rare-earth nanoparticles in mice can cause behavioral alterations including cognitive deficits, anxiety, and depression-like behavior. Using an open-field test and a morris water maze, we showed that long-term exposure to rare-earth nanoparticles may lead to significant depression, anxiety-like behavior, and memory impairment. The histopathological investigation on the neurotoxicological effects of nanoparticles indicated a significant decrease in cell viability after seven days' nanoparticle exposure. Western blotting analysis suggested that the changes of ATP-citrate lyase (ACLY) and O-linked N-acetylglucosamine transferase (OGT, a unique glycosyltransferase enzyme) played important roles in neurobehavioral disorders in mice. These findings provide a pathway to understand the cytotoxicity of rare-earth nanoparticles for medial applications and offer insights into the risk of these nanoparticles in biological systems.