title: Altered pulmonary defense system in lung injury induced by didecyldimethylammonium chloride in mice.
abstract: Didecyldimethylammonium chloride (DDAC), a representative dialkyl-quaternary ammonium compound (QAC), could contaminate working atmospheres when used in disinfectant operation and adversely affect human health. Furthermore, the development of bacteria resistant to DDAC might become public health concern. We postulated that DDAC instillation in the lungs alters pulmonary antioxidant and antimicrobial responses and increases susceptibility to systemic administration of a bacterial component lipopolysaccharide (LPS). Mice were intratracheally instilled with DDAC and sacrificed 1, 3, or 7 days after treatment. Pulmonary cytotoxicity in recovered bronchoalveolar lavage was evident on Days 1 and 7, and inflammatory cell influx and interleukin-6 expression peaked on Day 7, in association with altered antioxidant and antimicrobial responses, as demonstrated by measuring heme oxygenase-1, glutathione peroxidase 2, lactoferrin, and mouse β-defensin-2 and -3 mRNA in the lung samples. The impaired defense system tended to enhance the inflammatory reaction caused by a systemic administration of LPS; the effect was in association with increased expression of toll-like receptor-4 mRNA. The results suggest that DDAC alters pulmonary defense system, which may contribute to susceptibility to an exogenous infectious agent.
authors.affiliation: Laboratory of Pathology, The Institute of Environmental Toxicology, Joso, Ibaraki, Japan.
authors.forename: Aya
authors.initials: A
authors.lastname: Ohnuma
authors.forename: Toshinori
authors.initials: T
authors.lastname: Yoshida
authors.forename: Haruka
authors.initials: H
authors.lastname: Horiuchi
authors.forename: Junko
authors.initials: J
authors.lastname: Fukumori
authors.forename: Mariko
authors.initials: M
authors.lastname: Tomita
authors.forename: Sayuri
authors.initials: S
authors.lastname: Kojima
authors.forename: Naofumi
authors.initials: N
authors.lastname: Takahashi
authors.forename: Tomoki
authors.initials: T
authors.lastname: Fukuyama
authors.forename: Koichi
authors.initials: K
authors.lastname: Hayashi
authors.forename: Satoru
authors.initials: S
authors.lastname: Yamaguchi
authors.forename: Ryoichi
authors.initials: R
authors.lastname: Ohtsuka
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Kashimoto
authors.forename: Maki
authors.initials: M
authors.lastname: Kuwahara
authors.forename: Makio
authors.initials: M
authors.lastname: Takeda
authors.forename: Tadashi
authors.initials: T
authors.lastname: Kosaka
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Nakashima
authors.forename: Takanori
authors.initials: T
authors.lastname: Harada
mesh_terms: D055371:Acute Lung Injury / Q000139:chemically induced* / Q000235:genetics / Q000378:metabolism; D000395:Air Pollutants, Occupational / Q000633:toxicity*; D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry / Q000166:cytology; D015870:Gene Expression / Q000187:drug effects; D005979:Glutathione Peroxidase / Q000235:genetics / Q000378:metabolism; D051547:Heme Oxygenase-1 / Q000235:genetics / Q000378:metabolism; D007113:Immunity, Innate / Q000187:drug effects* / Q000235:genetics; D015850:Interleukin-6 / Q000378:metabolism; D007442:Intubation, Intratracheal; D007781:Lactoferrin / Q000235:genetics / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology; D008168:Lung / Q000187:drug effects* / Q000473:pathology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D000644:Quaternary Ammonium Compounds / Q000633:toxicity*; D051197:Toll-Like Receptor 4 / Q000235:genetics / Q000378:metabolism; D023083:beta-Defensins / Q000235:genetics / Q000378:metabolism
chemical_list: D000395:Air Pollutants, Occupational; D015850:Interleukin-6; D008070:Lipopolysaccharides; D000644:Quaternary Ammonium Compounds; C493487:Tlr4 protein, mouse; D051197:Toll-Like Receptor 4; D023083:beta-Defensins; C540070:beta-defensin 3, mouse; C492172:Gpx2 protein, mouse; D005979:Glutathione Peroxidase; D051547:Heme Oxygenase-1; D007781:Lactoferrin; C027118:didecyldimethylammonium