Experimental rodent models exposed to fine particulate matter (PM2.5) highlighting the injuries in the central nervous system: A systematic review

Exposure to the air pollution represents a major health risk, particulate matter is referred as harmful component of the environmental contamination. The central nervous system emerged as target to damages related to particulate matter exposure. This review presents the morphophysiological findings in the central nervous system of rodent models related to particulate matter 2.5 (PM2.5) exposure, published between 2016 to 2021. The data were collected in the scientific databases, PubMed, Springer Link, Science Direct and Web of Science using the string [(air pollution OR particulate matter OR PM2.5 AND central nervous system OR CNS OR brain AND neurodegeneration)]. To refine the article search, inclusion and exclusion criteria where applied, resulting in 48 articles selected to compose this review. The major neurological outcomes reported in the studies were microglial activation, increase proinflammatory citokines, oxidative stress, protein aggregation, synaptic imbalance, apoptosis, morphological changes, memory and behavioral impairment and other changes (hormonal changes, body weight and gene expression). These findings indicate injuries in the central nervous system that alters the neurodevelopment, anatomy, physiology, immune response, among others, that are related to particulate matter exposure and are closely associated to human neurological outcomes. The performed studies provide evidences of the mechanism involved in neurodegenerative diseases (e.g. Alzheimer and Parkinson) and neurological behavior impairment (e.g. Autism like, depression, anxiety).