Neurotoxicity of metal-containing nanoparticles and implications in glial cells

With the development of nanotechnology, metal-containing nanoparticles are used widely in the diagnosis, monitoring and treatment of central nervous system (CNS) diseases. The neurotoxicity of these nanoparticles has drawn attention. Glial cells (particularly microglial cells and astrocytes) have important functions in the CNS. Neural disorders are related to functional/histologic damage to glial cells. Dysfunctions of microglial cells or astrocytes injure the brain, and cause the neurodegeneration seen in Alzheimer's disease and Parkinson's disease. We have summarized the route of access of metal-containing nanoparticles to the CNS, as well as their neurotoxicity and potential molecular mechanisms involved in glial cells. Metal-containing nanoparticles cross or bypass the blood-brain barrier, access the CNS and cause neurotoxicity. The potential mechanisms are related to inflammation, oxidative stress, DNA and/or mitochondrial damage and cell death, all of which are mediated by microglial cell activation, inflammatory factor release, generation of reactive oxygen species, apoptosis and/or autophagy in glial cells. Moreover, these processes increase the burden of the CNS and even accelerate the occurrence or development of neurodegenerative diseases. Some important signaling pathways involved in the mechanism of neurotoxicity in glial cells caused by nanoparticles are also discussed.

Automated summary

Metal-containing nanoparticles are widely used in the diagnosis, monitoring, and treatment of central nervous system diseases, but their neurotoxicity, especially on glial cells, is a cause for concern. Dysfunctions in microglial cells and astrocytes can damage the brain and contribute to the development of neurodegenerative diseases like Alzheimer's and Parkinson's. The mechanisms of neurotoxicity involve inflammation, oxidative stress, DNA damage, and cell death in glial cells, ultimately increasing the burden on the central nervous system.