A vast study reveals that prolonged exposure to fine particles promotes the formation of Lewy bodies, responsible for serious and incurable neurodegenerative diseases.
A monumental study connecting pollution and neurodegenerative diseases
For the first time, researchers have exploited hospital data from 56.5 million American patients admitted between 2000 and 2014 for neurodegenerative diseases. By focusing on patients with pathologies related to Lewy’s bodies, they have established a striking statistical link. According to the team, each increase in the concentration of fine particles (PM2.5) corresponded to an increase of 17 % of the risk of Parkinson’s disease and 12 % of the risk of lewy bodies.
Xiao Wu, assistant professor of biostatis at Columbia University, insists on the strength of this discovery: “The statistical association that we have highlighted is even stronger than what previous studies had found by bringing together all dementia, including Alzheimer’s – highlighting the formation of Lewy’s bodies as a potentially decisive path which deserves an in -depth biological survey “.
When pollution triggers toxic clusters in the brain
The team led by Xiaobo Mao, associate professor of neurology at Johns Hopkins, exhibited mice with air pollution made up of fine particles from various origins (China, Europe, United States). The results are striking: these exhibitions have led to the formation of abnormal alpha-synuclein protein pile, identical to those observed in the brain of human patients with Lewy bodies.
As Xiaobo Mao explains: “We have identified a new Lewy body strain formed after exposure to air pollution. By defining this strain, we hope to establish a specific target for future drugs aimed at slowing down the progression of neurodegenerative diseases marked by Lewy bodies “.
In normal mice, prolonged exposure caused brain atrophy, the death of nerve cells and a cognitive decline, as described Ted Dawson, director of the Johns Hopkins cellular institute: “In normal mice, we have observed cerebral atrophy, cell death and cognitive decline – symptoms similar to those of Lewy’s body dementia. But in mice devoid of alpha-synuclein, the brain has presented no significant change“.
Towards new therapeutic avenues, but unknowns remain
Researchers also noticed that changes in gene expression in the brain of exposed mice were similar to those observed in human patients. Shizhong Han Principal Researcher at the Lieber Institute underlines: “This suggests that pollution could not only trigger the accumulation of toxic proteins but also cause genetic expression changes linked to the disease in the human brain “.
Haiqing Liu, postdoctoral researcher at the Johns Hopkins University Faculty of Medicine, adds: “This suggests that the harmful effects of fine particles could be largely consistent in different regions “.
Finally, Xiaadi Zhang, co-author of the study, insists on the rest of the work: “Our next objective is to understand which specific components of air pollution are at the origin of these effects. Understanding this could help guide public health efforts to reduce harmful exposures and reduce the risk of illness“.
This discovery therefore opens a double perspective: strengthen environmental prevention and explore a new therapeutic target to slow the progression of still incurable neurodegenerative diseases.