Air Pollution’s Impact on Cognitive Decline and the Neurotoxicity of Particulate Matter: Masashi Kitazawa, PhD

WATCH TIME: 5 minutes

"This data suggests that exposure to particulate matter (PM) or air pollution is causing some neurotoxicity or brain damage at certain levels. In the case of the Alzheimer disease (AD) mice model, the results show acceleration of amyloid-β pathology and neurodegeneration on animals that received the air pollution. Thus, we think that the PM exposure or the exposure to the air pollution may increase the risk of the AD onset.”

Alzheimer disease (AD), the most common cause of dementia in the older population, is an increasing public health crisis worldwide. Although there has been an immense amount of research conducted on all aspects of AD, the exact origins of the disease remain unclear. In recent research, there is a growing amount of evidence that suggests that environmental toxicants, more specifically such as air pollution, may be of cause to onset of AD.¹

Findings from a recent study published in Toxicological Sciences demonstrated that exposure to traffic-related air pollution in Irvine, California, led to memory loss, cognitive decline, and triggered neurological pathways associated with the onset of AD.² Researchers compared 3- and 9-month-old mice in 2 groups, with 1 group exposed to ultrafine particulate matter (PM) via ambient air and the other group exposed to purified air for 12 weeks. When conducting memory and cognitive function tests, researchers observed that both benchmarks were impaired by exposure to PM. In addition, older mice models showed brain plaque buildup and glial cell activation, both known for increasing inflammation related to the onset of AD.

Senior investigator Masashi Kitazawa, PhD, associate professor of environmental & Occupational Health, University of California, Irvine, down in an interview with NeurologyLive® to discuss the recently published research. He talked about the recent epidemiological studies revealing the increased risk of AD among individuals living near heavy traffic areas. He also talked about how animal studies, using concentrated PM, demonstrated the impact of air pollution on brain function. Furthermore, he mentioned some of the specific effects that were observed in animal models exposed to PM, and what implications the findings have for research in AD.

REFERENCES
1. UCI study shows traffic-related air pollution in Irvine weakens brain function. News Release. University of California, Irvine. Published May 11, 2023. Accessed June 26, 2023. https://news.uci.edu/2023/05/11/uc-irvine-study-shows-traffic-related-air-pollution-in-irvine-weakens-brain-function/#:~:text=Irvine%2C%20Calif.%2C%20May%2011,the%20onset%20of%20Alzheimer's%20disease.
2. Kilian JG, Mejias-Ortega M, Hsu HW, et al. Exposure to quasi-ultrafine particulate matter accelerates memory impairment and Alzheimer's disease-like neuropathology in the AppNL-G-F knock-in mouse model. Toxicol Sci. 2023;193(2):175-191. doi:10.1093/toxsci/kfad036