Alva Hansson, Gregory Rankin, Oskari Uski, Maria Friberg, Jamshid Pourazar, Robert Lindgren, Natxo García-López, Christoffer Boman, Thomas Sandström, Annelie Behndig, Ala Muala
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引用次数: 1
Abstract
Background: Exposure to wood smoke has been shown to contribute to adverse respiratory health effects including airway infections, but the underlying mechanisms are unclear. A preceding study failed to confirm any acute inflammation or cell influx in bronchial wash (BW) or bronchoalveolar lavage (BAL) 24 h after wood smoke exposure but showed unexpected reductions in leukocyte numbers. The present study was performed to investigate responses at an earlier phase, regarding potential development of acute inflammation, as well as indications of cytotoxicity.
Methods: In a double-blind, randomised crossover study, 14 healthy participants were exposed for 2 h to filtered air and diluted wood smoke from incomplete wood log combustion in a common wood stove with a mean particulate matter concentration of 409 µg/m3. Bronchoscopy with BW and BAL was performed 6 h after exposure. Differential cell counts, assessment of DNA-damage and ex vivo analysis of phagocytic function of phagocytosing BAL cells were performed. Wood smoke particles were also collected for in vitro toxicological analyses using bronchial epithelial cells (BEAS-2B) and alveolar type II-like cells (A549).
Results: Exposure to wood smoke increased BAL lactate dehydrogenase (LDH) (p = 0.04) and reduced the ex vivo alveolar macrophage phagocytic capacity (p = 0.03) and viability (p = 0.02) vs. filtered air. BAL eosinophil numbers were increased after wood smoke (p = 0.02), while other cell types were unaffected in BW and BAL. In vitro exposure to wood smoke particles confirmed increased DNA-damage, decreased metabolic activity and cell cycle disturbances.
Conclusions: Exposure to wood smoke from incomplete combustion did not induce any acute airway inflammatory cell influx at 6 h, apart from eosinophils. However, there were indications of a cytotoxic reaction with increased LDH, reduced cell viability and impaired alveolar macrophage phagocytic capacity. These findings are in accordance with earlier bronchoscopy findings at 24 h and may provide evidence for the increased susceptibility to infections by biomass smoke exposure, reported in population-based studies.
期刊介绍:
Particle and Fibre Toxicology is an online journal that is open access and peer-reviewed. It covers a range of disciplines such as material science, biomaterials, and nanomedicine, focusing on the toxicological effects of particles and fibres. The journal serves as a platform for scientific debate and communication among toxicologists and scientists from different fields who work with particle and fibre materials. The main objective of the journal is to deepen our understanding of the physico-chemical properties of particles, their potential for human exposure, and the resulting biological effects. It also addresses regulatory issues related to particle exposure in workplaces and the general environment. Moreover, the journal recognizes that there are various situations where particles can pose a toxicological threat, such as the use of old materials in new applications or the introduction of new materials altogether. By encompassing all these disciplines, Particle and Fibre Toxicology provides a comprehensive source for research in this field.