Brake dust exposure exacerbates inflammation and transiently compromises phagocytosis in macrophages
File(s)
Published version
OA Location
Author(s)
Type
Journal Article
Abstract
Studies have emphasised the importance of combustion-derived particles in eliciting adverse health effects, especially those produced by diesel vehicles. In contrast, few investigations have explored the potential toxicity of particles derived from tyre and brake wear, despite their significant contributions to total roadside particulate mass. The objective of this study was to compare the relative toxicity of compositionally distinct brake abrasion dust (BAD) and diesel exhaust particles (DEP) in a cellular model that is relevant to human airways. Although BAD contained considerably more metals/metalloids than DEP (as determined by inductively coupled plasma mass spectrometry) similar toxicological profiles were observed in U937 monocyte-derived macrophages following 24 h exposures to 4–25 μg ml−1 doses of either particle type. Responses to the particles were characterised by dose-dependent decreases in mitochondrial depolarisation (p ≤ 0.001), increased secretion of IL-8, IL-10 and TNF-α (p ≤ 0.05 to p ≤ 0.001) and decreased phagocytosis of S. aureus (p ≤ 0.001). This phagocytic deficit recovered, and the inflammatory response resolved when challenged cells were incubated for a further 24 h in particle-free media. These responses were abrogated by metal chelation using desferroxamine. At minimally cytotoxic doses both DEP and BAD perturbed bacterial clearance and promoted inflammatory responses in U937 cells with similar potency. These data emphasise the requirement to consider contributions of abrasion particles to traffic-related clinical health effects.
Date Issued
2020-03-01
Date Acceptance
2019-12-06
Citation
Metallomics: integrated biometal science, 2020, 12 (3), pp.371-386
ISSN
1756-5901
Publisher
Royal Society of Chemistry
Start Page
371
End Page
386
Journal / Book Title
Metallomics: integrated biometal science
Volume
12
Issue
3
Copyright Statement
© The Royal Society of Chemistry 2020. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence (http://creativecommons.org/licenses/by/3.0/).
Identifier
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000527735100005&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
Subjects
Science & Technology
Life Sciences & Biomedicine
Biochemistry & Molecular Biology
AIRBORNE PARTICULATE MATTER
AIR-POLLUTION
OXIDATIVE STRESS
EPITHELIAL-CELLS
TYROSINE PHOSPHATASES
ALVEOLAR MACROPHAGES
RADICAL GENERATION
PARTICLE EMISSIONS
RESPIRATORY BURST
DESFERRIOXAMINE-B
Publication Status
Published
Date Publish Online
2020-01-09