title: Effects of two Asian sand dusts transported from the dust source regions of Inner Mongolia and northeast China on murine lung eosinophilia.
abstract: The quality and quantity of toxic materials adsorbed onto Asian sand dust (ASD) are different based on dust source regions and passage routes. The aggravating effects of two ASDs (ASD1 and ASD2) transported from the source regions of Inner Mongolia and northeast China on lung eosinophilia were compared to clarify the role of toxic materials in ASD. The ASDs contained different amounts of lipopolysaccharides (LPS) and β-glucan (ASD1<ASD2) and SiO2 (ASD1>ASD2). CD-1 mice were instilled intratracheally with ASD1, ASD2 and/or ovalbumin (OVA) four times at 2-week intervals. ASD1 and ASD2 enhanced eosinophil recruitment induced by OVA in the submucosa of the airway, with goblet cell proliferation in the bronchial epithelium. ASD1 and ASD2 synergistically increased OVA-induced eosinophil-relevant cytokines interleukin-5 (IL-5), IL-13 (ASD1<ASD2) and chemokine eotaxin (ASD1>ASD2) in bronchoalveolar lavage fluid. ASD2 aggravating effects on lung eosinophilia were greater than ASD1. The role of LPS and β-glucan in ASD2 on the production of pro-inflammatory mediators was assessed using in vitro bone marrow-derived macrophages (BMDMs) from wild type, Toll-like receptor 2-deficient (TLR2-/-), TLR4-/-, and MyD88-/- mice (on Balb/c background). ASD2-stimulated TLR2-/- BMDMs enhanced IL-6, IL-12, TNF-α, MCP-1 and MIP-1α secretion compared with ASD2-stimulated TLR4-/- BMDMs. Protein expression from ASD2-stimulated MyD88-/- BMDM were very low or undetectable. The in vitro results indicate that lung eosinophilia caused by ASD is TLR4 dependent. Therefore, the aggravation of OVA-related lung eosinophilia by ASD may be dependent on toxic substances derived from microbes, such as LPS, rather than SiO2.
authors.affiliation: Environment and Chronic Non-communicable Disease Research Center, College of Public Health, China Medical University, 11001 Shenyang, China; Department of Health Sciences, Oita University of Nursing and Health Sciences, 870-1201 Oita, Japan. Electronic address: hemiao.cmu@gmail.com.
authors.forename: Miao
authors.initials: M
authors.lastname: He
authors.forename: Takamichi
authors.initials: T
authors.lastname: Ichinose
authors.forename: Yuan
authors.initials: Y
authors.lastname: Song
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Yoshida
authors.forename: Keiichi
authors.initials: K
authors.lastname: Arashidani
authors.forename: Seiichi
authors.initials: S
authors.lastname: Yoshida
authors.forename: Boying
authors.initials: B
authors.lastname: Liu
authors.forename: Masataka
authors.initials: M
authors.lastname: Nishikawa
authors.forename: Hirohisa
authors.initials: H
authors.lastname: Takano
authors.forename: Guifan
authors.initials: G
authors.lastname: Sun
mesh_terms: D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology; D002478:Cells, Cultured; D002681:China; D004391:Dust / Q000032:analysis*; D007249:Inflammation / Q000139:chemically induced / Q000453:epidemiology / Q000473:pathology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D018345:Mice, Knockout; D011657:Pulmonary Eosinophilia / Q000139:chemically induced* / Q000453:epidemiology / Q000473:pathology*; D012822:Silicon Dioxide / Q000633:toxicity*
chemical_list: D004391:Dust; D012822:Silicon Dioxide
keywords: Asian sand dust; Bone marrow macrophages; Cytokines; Knockout mice; Lipopolysaccharide; Lung eosinophilia