In my opinion, the reason air pollution effects dementia risk is through activation of Heat Shock Proteins and I think it is the most valuable place to be investing in research.
Heat Shock Proteins in Alzheimer’s Disease: Role and Targeting
Heat Shock Proteins in Alzheimer’s Disease: Role and Targeting
"In summary, the mechanism of PM2.5-induced brain damage involves entry via the olfactory system and BBB, activation of glial cells, neuroinflammation, oxidative stress, BBB disruption, and downstream neurodegenerative changes."
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