Cellular mechanisms of neodymium oxide-induced neurodevelopmental damage and memory impairment

Neodymium (Nd) is a rare earth element (REE) with numerous applications in medicine and high-technology manufacturing. However, Nd is also an emerging environmental contaminant, so it is essential to examine potential mechanisms of toxicity. Here, we demonstrate that neodymium oxide (Nd₂O₃) can cross the placental barrier following gavage ingestion by rats dam and accumulate in the fetus. This fetal exposure disrupted the underdeveloped blood-brain barrier (BBB) and entered the brain, causing oxidative stress, glutamate release, calcium dysregulation, and mitochondrial damage in both neurons and astrocytes. We also observed that damaged astrocyte mitochondria were transported to neurons through tunneling nanotubes (TNTs), resulting in impaired neural development that manifested as spatial learning and memory deficits at the juvenile stage. These results suggest that prenatal Nd₂O₃ exposure can induce neurodevelopmental damage. Further, these findings identify potential therapeutic targets for preventing childhood intellectual impairment.