» Articles » PMID: 21864400

Air Pollution & the Brain: Subchronic Diesel Exhaust Exposure Causes Neuroinflammation and Elevates Early Markers of Neurodegenerative Disease

Overview
Publisher Biomed Central
Date 2011 Aug 26
PMID 21864400
Citations 133
Authors
Affiliations
Soon will be listed here.
Abstract

Background: Increasing evidence links diverse forms of air pollution to neuroinflammation and neuropathology in both human and animal models, but the effects of long-term exposures are poorly understood.

Objective: We explored the central nervous system consequences of subchronic exposure to diesel exhaust (DE) and addressed the minimum levels necessary to elicit neuroinflammation and markers of early neuropathology.

Methods: Male Fischer 344 rats were exposed to DE (992, 311, 100, 35 and 0 μg PM/m³) by inhalation over 6 months.

Results: DE exposure resulted in elevated levels of TNFα at high concentrations in all regions tested, with the exception of the cerebellum. The midbrain region was the most sensitive, where exposures as low as 100 μg PM/m³ significantly increased brain TNFα levels. However, this sensitivity to DE was not conferred to all markers of neuroinflammation, as the midbrain showed no increase in IL-6 expression at any concentration tested, an increase in IL-1β at only high concentrations, and a decrease in MIP-1α expression, supporting that compensatory mechanisms may occur with subchronic exposure. Aβ42 levels were the highest in the frontal lobe of mice exposed to 992 μg PM/m³ and tau [pS199] levels were elevated at the higher DE concentrations (992 and 311 μg PM/m³) in both the temporal lobe and frontal lobe, indicating that proteins linked to preclinical Alzheimer's disease were affected. α Synuclein levels were elevated in the midbrain in response to the 992 μg PM/m³ exposure, supporting that air pollution may be associated with early Parkinson's disease-like pathology.

Conclusions: Together, the data support that the midbrain may be more sensitive to the neuroinflammatory effects of subchronic air pollution exposure. However, the DE-induced elevation of proteins associated with neurodegenerative diseases was limited to only the higher exposures, suggesting that air pollution-induced neuroinflammation may precede preclinical markers of neurodegenerative disease in the midbrain.

Citing Articles

Acute particulate matter exposure diminishes executive cognitive functioning after four hours regardless of inhalation pathway.

Faherty T, Raymond J, McFiggans G, Pope F Nat Commun. 2025; 16(1):1339.

PMID: 39915448 PMC: 11803098. DOI: 10.1038/s41467-025-56508-3.


Bidirectional relationship between olfaction and Parkinson's disease.

Kim J, Bandres-Ciga S, Heilbron K, Blauwendraat C, Noyce A NPJ Parkinsons Dis. 2024; 10(1):232.

PMID: 39639040 PMC: 11621548. DOI: 10.1038/s41531-024-00838-4.


Exposure to biodiesel exhaust is less harmful than exposure to mineral diesel exhaust on blood-brain barrier integrity in a murine model.

Nesbit M, Ko C, Mamo J, Lam V, Landwehr K, Larcombe A Front Neurosci. 2024; 18:1440118.

PMID: 39347532 PMC: 11427429. DOI: 10.3389/fnins.2024.1440118.


Air pollution amyloidogenesis is attenuated by the gamma-secretase modulator GSM-15606.

Godoy-Lugo J, Thorwald M, Cacciottolo M, DAgostino C, Chakhoyan A, Sioutas C Alzheimers Dement. 2024; 20(9):6107-6114.

PMID: 39132765 PMC: 11497728. DOI: 10.1002/alz.14086.


Transcriptomics and weighted protein network analyses of the LRRK2 protein interactome reveal distinct molecular signatures for sporadic and LRRK2 Parkinson's Disease.

Zhao Y, Bracher-Smith M, Li Y, Harvey K, Escott-Price V, Lewis P NPJ Parkinsons Dis. 2024; 10(1):144.

PMID: 39097579 PMC: 11297940. DOI: 10.1038/s41531-024-00761-8.


References
1.
McCoy M, Tansey M . TNF signaling inhibition in the CNS: implications for normal brain function and neurodegenerative disease. J Neuroinflammation. 2008; 5:45. PMC: 2577641. DOI: 10.1186/1742-2094-5-45. View

2.
McDonald J, Barr E, White R, Chow J, Schauer J, Zielinska B . Generation and characterization of four dilutions of diesel engine exhaust for a subchronic inhalation study. Environ Sci Technol. 2004; 38(9):2513-22. DOI: 10.1021/es035024v. View

3.
Glass C, Saijo K, Winner B, Marchetto M, Gage F . Mechanisms underlying inflammation in neurodegeneration. Cell. 2010; 140(6):918-34. PMC: 2873093. DOI: 10.1016/j.cell.2010.02.016. View

4.
Lucas S, Rothwell N, Gibson R . The role of inflammation in CNS injury and disease. Br J Pharmacol. 2006; 147 Suppl 1:S232-40. PMC: 1760754. DOI: 10.1038/sj.bjp.0706400. View

5.
Campbell A, Araujo J, Li H, Sioutas C, Kleinman M . Particulate matter induced enhancement of inflammatory markers in the brains of apolipoprotein E knockout mice. J Nanosci Nanotechnol. 2009; 9(8):5099-104. DOI: 10.1166/jnn.2009.gr07. View