title: Asian sand dust enhances murine lung inflammation caused by Klebsiella pneumoniae.
abstract: Inhaling concomitants from Asian sand dust (ASD) may result in exacerbation of pneumonia by the pathogen. The exacerbating effect of ASD on pneumonia induced by Klebsiella pneumoniae (KP) was investigated in ICR mice. The organic substances adsorbed onto ASD collected from the atmosphere of Iki-island in Japan were excluded by heat treatment at 360°C for 30min. ICR mice were instilled intratracheally with ASD at doses of 0.05mg or 0.2mg/mouse four times at 2-week intervals (total dose of 0.2mg or 0.8mg/mouse) and were administrated with ASD in the presence or absence of KP at the last intratracheal instillation. Pathologically, ASD caused exacerbation of pneumonia by KP as shown by increased inflammatory cells within the bronchiolar and the alveolar compartments. ASD enhanced the neutrophil number dose dependently as well as the expression of cytokines (IL-1β, IL-6, IL-12, IFN-γ, TNF-α) and chemokines (KC, MCP-1, MIP-1α) related to KP in BALF. In an in vitro study using RAW264.7 cells, combined treatment of ASD and KP increased gene expression of IL-1β, IL-6, IFN-β, KC, MCP-1, and MIP-1α. The same treatment tended to increase the protein level of IL-1β, TNF-α and MCP-1 in a culture medium compared to each treatment alone. The combined treatment tended to increase the gene expression of Toll-like receptor 2 (TLR2), and NALP3, ASC and caspase-1 compared with KP alone. These results suggest that the exacerbation of pneumonia by ASD+KP was due to the enhanced production of pro-inflammatory mediators via activation of TLR2 and NALP3 inflammasome pathways in alveolar macrophages.
authors: Department of Environmental and Occupational Health, College of Public Health, China Medical University, 11001, Shenyang, China.
authors: Miao
authors: M
authors: He
authors: Takamichi
authors: T
authors: Ichinose
authors: Seiichi
authors: S
authors: Yoshida
authors: Shoji
authors: S
authors: Yamamoto
authors: Ken-ichiro
authors: K
authors: Inoue
authors: Hirohisa
authors: H
authors: Takano
authors: Rie
authors: R
authors: Yanagisawa
authors: Masataka
authors: M
authors: Nishikawa
authors: Ikuko
authors: I
authors: Mori
authors: Guifan
authors: G
authors: Sun
authors: Takayuki
authors: T
authors: Shibamoto
mesh_terms: D000391:Air Microbiology; D000393:Air Pollutants / Q000633:toxicity; D000818:Animals; D001992:Bronchoalveolar Lavage Fluid; D004391:Dust; D005786:Gene Expression Regulation; D058847:Inflammasomes / Q000378:metabolism; D007249:Inflammation / Q000209:etiology* / Q000382:microbiology / Q000473:pathology; D018836:Inflammation Mediators / Q000378:metabolism; D019570:Inhalation Exposure; D007564:Japan; D007710:Klebsiella Infections / Q000209:etiology / Q000382:microbiology / Q000473:pathology*; D007711:Klebsiella pneumoniae / Q000302:isolation & purification*; D008168:Lung / Q000382:microbiology / Q000473:pathology*; D016676:Macrophages, Alveolar / Q000378:metabolism / Q000382:microbiology; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D011014:Pneumonia / Q000209:etiology* / Q000382:microbiology / Q000473:pathology
chemical_list: D000393:Air Pollutants; D004391:Dust; D058847:Inflammasomes; D018836:Inflammation Mediators