Research progress on effect of nanoparticles on olfactory bulb and its mechanism

The olfactory bulb is part of the brain cortex, and is a relay station for olfactory impulses to the central nervous system, which can collect olfactory impulses and regulate information about odors from the nasal epithelium. In recent years, some epidemiological and animal experimental results show that the nanoparticles can enter the olfactory bulb and other regions of the brain along the olfactory system through respiratory exposure, inducing neuroinflammation, oxidative stress, and neurotransmitter disorder. Nanoparticles exposure can further lead to pathological changes in olfactory bulb, such as neuronal hypertrophy, condensation and marginalization of chromatin in nuclei to affect the olfactory function. In this paper, the physiological process of nanoparticles entering the olfactory bulb along the axons of olfactory sensory neurons after respiratory exposure was reviewed, its toxic effect on olfactory bulb and related mechanism were summarized, aiming to provide a reasonable basis for prevention of injury of olfactory bulb and related system caused by respiratory exposure to nanoparticles.