title: Protective effects of pulmonary epithelial lining fluid on oxidative stress and DNA single-strand breaks caused by ultrafine carbon black, ferrous sulphate and organic extract of diesel exhaust particles.
abstract: Pulmonary epithelial lining fluid (ELF) is the first substance to make contact with inhaled particulate matter (PM) and interacts chemically with PM components. The objective of this study was to determine the role of ELF in oxidative stress, DNA damage and the production of proinflammatory cytokines following physicochemical exposure to PM. Ultrafine carbon black (ufCB, 15 nm; a model carbonaceous core), ferrous sulphate (FeSO(4); a model transition metal) and a diesel exhaust particle (DEP) extract (a model organic compound) were used to examine the acellular oxidative potential of synthetic ELF and non-ELF systems. We compared the effects of exposure to ufCB, FeSO(4) and DEP extract on human alveolar epithelial Type II (A549) cells to determine the levels of oxidative stress, DNA single-strand breaks and interleukin-8 (IL-8) production in ELF and non-ELF systems. The effects of ufCB and FeSO(4) on the acellular oxidative potential, cellular oxidative stress and DNA single-strand breakage were mitigated significantly by the addition of ELF, whereas there was no decrease following treatment with the DEP extract. There was no significant effect on IL-8 production following exposure to samples that were suspended in ELF/non-ELF systems. The results of the present study indicate that ELF plays an important role in the initial defence against PM in the pulmonary environment. Experimental components, such as ufCB and FeSO(4), induced the production of oxidative stress and led to DNA single-strand breaks, which were moderately prevented by the addition of ELF. These findings suggest that ELF plays a protective role against PM-driven oxidative stress and DNA damage.
authors.affiliation: School of Respiratory Therapy, College of Medicine, Taipei Medical University, Taipei, Taiwan.
authors.forename: Hsiao-Chi
authors.initials: HC
authors.lastname: Chuang
authors.forename: Yi-Ling
authors.initials: YL
authors.lastname: Cheng
authors.forename: Yu-Chen
authors.initials: YC
authors.lastname: Lei
authors.forename: Hui-Hsien
authors.initials: HH
authors.lastname: Chang
authors.forename: Tsun-Jen
authors.initials: TJ
authors.lastname: Cheng
mesh_terms: D053904:DNA Breaks, Single-Stranded; D004847:Epithelial Cells / Q000187:drug effects / Q000276:immunology / Q000473:pathology; D005296:Ferrous Compounds / Q000633:toxicity*; D006801:Humans; D008168:Lung / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D018384:Oxidative Stress / Q000187:drug effects* / Q000276:immunology; D052638:Particulate Matter / Q000633:toxicity*; D017382:Reactive Oxygen Species / Q000378:metabolism; D053260:Soot / Q000633:toxicity*; D001335:Vehicle Emissions / Q000633:toxicity*
chemical_list: D005296:Ferrous Compounds; D052638:Particulate Matter; D017382:Reactive Oxygen Species; D053260:Soot; D001335:Vehicle Emissions; C020748:ferrous sulfate