Article

Endotoxin in concentrated coarse and fine ambient particles induces acute systemic inflammation in controlled human exposures

Environmental Health, Harvard School of Public Health, Boston, Massachusetts, USA.
Occupational and environmental medicine (Impact Factor: 3.23). 11/2013; 70(11):761-7. DOI: 10.1136/oemed-2013-101498
Source: PubMed

ABSTRACT Knowledge of the inhalable particulate matter components responsible for health effects is important for developing targeted regulation.
In a double-blind randomised cross-over trial of controlled human exposures to concentrated ambient particles (CAPs) and their endotoxin and (1→3)-β-D-glucan components, we evaluated acute inflammatory responses.
35 healthy adults were exposed to five 130-min exposures at rest: (1) fine CAPs (∼250 µg/m(3)); (2) coarse CAPs (∼200 µg/m(3)); (3) second coarse CAPs (∼200 µg/m(3)); (4) filtered air; and (5) medical air. Induced sputum cell counts were measured at screening and 24 h postexposure. Venous blood total leucocytes, neutrophils, interleukin-6 and high-sensitivity C reactive protein (CRP) were measured pre-exposure, 3 and 24 h postexposure.
Relative to filtered air, an increase in blood leucocytes 24 h (but not 3 h) postexposure was significantly associated with coarse (estimate=0.44×10(9) cells/L (95% CI 0.01 to 0.88); n=132) and fine CAPs (0.68×10(9) cells /L (95% CI 0.19 to 1.17); n=132), but not medical air. Similar associations were found with neutrophil responses. An interquartile increase in endotoxin (5.4 ng/m(3)) was significantly associated with increased blood leucocytes 3 h postexposure (0.27×10(9) cells/L (95% CI 0.03 to 0.51); n=98) and 24 h postexposure (0.37×10(9) cells/L (95% CI 0.12 to 0.63); n=98). This endotoxin effect did not differ by particle size. There were no associations with glucan concentrations or interleukin-6, CRP or sputum responses.
In healthy adults, controlled coarse and fine ambient particle exposures independently induced acute systemic inflammatory responses. Endotoxin contributes to the inflammatory role of particle air pollution.

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    • "). PM with high PAH content has been shown as an effective inducer of oxidative stress and inflammatory response in cellular and animal studies (Gualtieri et al., 2010; Wittkopp et al., 2013). In addition to PAHs, contributions of endotoxin to the inflammatory effects of different PM have also been widely reported by cellular, animal and human studies (Osornio-Vargas et al., 2003; Arimoto et al., 2005; Oeder et al., 2012; Behbod et al., 2013). Using similar cellular models, Gualtieri et al. (2010) have shown that PM-induced increase in IL-8, TNF-a and IL-6 was linked to the endotoxin on particle surface. "
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    ABSTRACT: In vitro tests using human adenocarcinomic alveolar epithelial cell line A549 and small mouse monocyte-macrophage cell line J774A.1 were conducted to test toxicity of six PM (particulate matter) samples from Beijing. The properties of the samples differ significantly. The production of inflammatory cytokine (TNF-α for J774A.1) and chemokine (IL-8 for A549) and the level of intracellular reactive oxygen species (ROS) were used as endpoints. There was a positive correlation between water soluble organic carbon and DTT-based redox activity. Both cell types produced increased levels of inflammatory mediators and had higher level of intracelllar ROS, indicating the presence of PM-induced inflammatory response and oxidative stress, which were dose-dependent and significantly different among the samples. The releases of IL-8 from A549 and TNF-α from J774A.1 were significantly correlated to PM size, Zeta potential, endotoxin, major metals, and polycyclic aromatic hydrocarbons. No correlation between ROS and these properties was identified.
    Environmental Pollution 05/2014; 191C:63-69. DOI:10.1016/j.envpol.2014.04.008 · 3.90 Impact Factor
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    • "). PM with high PAH content has been shown as an effective inducer of oxidative stress and inflammatory response in cellular and animal studies (Gualtieri et al., 2010; Wittkopp et al., 2013). In addition to PAHs, contributions of endotoxin to the inflammatory effects of different PM have also been widely reported by cellular, animal and human studies (Osornio-Vargas et al., 2003; Arimoto et al., 2005; Oeder et al., 2012; Behbod et al., 2013). Using similar cellular models, Gualtieri et al. (2010) have shown that PM-induced increase in IL-8, TNF-a and IL-6 was linked to the endotoxin on particle surface. "
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    ABSTRACT: In vitro tests using human adenocarcinomic alveolar epithelial cell line A549 and small mouse monocyte-macrophage cell line J774A.1 were conducted to test toxicity of six PM (particulate matter) samples from Beijing. The properties of the samples differ significantly. The production of inflammatory cytokine (TNF-α for J774A.1) and chemokine (IL-8 for A549) and the level of intracellular reactive oxygen species (ROS) were used as endpoints. There was a positive correlation between water soluble organic carbon and DTT-based redox activity. Both cell types produced increased levels of inflammatory mediators and had higher level of intracelllar ROS, indicating the presence of PM-induced inflammatory response and oxidative stress, which were dose-dependent and significantly different among the samples. The releases of IL-8 from A549 and TNF-α from J774A.1 were significantly correlated to PM size, Zeta potential, endotoxin, major metals, and polycyclic aromatic hydrocarbons. No correlation between ROS and these properties was identified.
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