title: Biological responses in rats exposed to cigarette smoke and Middle East sand (dust).
abstract: Respiratory symptoms are frequently reported in personnel deployed to the Middle East. This project characterized the respiratory toxicity of inhaled Iraqi sand (IS). Adult rats underwent a 6-wk inhalation to air or mainstream cigarette smoke (MSCS) (3 h/d, 5 d/wk) that included exposure to IS or crystalline silica (1 mg/m(3), 19 h/d, 7 d/wk) or air during the last 2 weeks. Assessments included motor activity, whole-body plethysmography, cytological and biochemical analysis of bronchoalveolar lavage fluid, lung metal burden, nasal and lung pathology, and changes in lung protein and gene expression. A number of metals including nickel, manganese, vanadium, and chromium were detected in IS. Elevated lung parenchyma aluminum, silica, barium, manganese, and vanadium concentrations were seen in IS-exposed rats, suggesting that several metals present in IS are bioavailable. Rats exposed to IS only developed mild inflammation in the anterior nose and lung. Silica inhalation was associated with some pulmonary responses that were not seen in IS-exposed rats, such as mild laryngeal and tracheal inflammation, mild tracheal epithelial hyperplasia, and elevated lung silica concentrations. MSCS inhalation with or without co-exposure to either IS or silica resulted in changes consistent with pulmonary inflammation and stress response. Rats exposed to MSCS and silica had more widespread airway lesions when compared with rats exposed to MSCS only. Silica-exposed rats had more robust pulmonary gene expression and proteomic responses than that seen in IS-exposed rat. Our studies show that the respiratory toxicity of IS is qualitatively similar to or less than that seen following short-term silica exposure.
authors.affiliation: College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607, USA. david_dorman@ncsu.edu
authors.forename: David C
authors.initials: DC
authors.lastname: Dorman
authors.forename: Vishwesh
authors.initials: V
authors.lastname: Mokashi
authors.forename: Dean J
authors.initials: DJ
authors.lastname: Wagner
authors.forename: Ayodele O
authors.initials: AO
authors.lastname: Olabisi
authors.forename: Brian A
authors.initials: BA
authors.lastname: Wong
authors.forename: Owen R
authors.initials: OR
authors.lastname: Moss
authors.forename: Jose A
authors.initials: JA
authors.lastname: Centeno
authors.forename: Gustavo
authors.initials: G
authors.lastname: Guandalini
authors.forename: David A
authors.initials: DA
authors.lastname: Jackson
authors.forename: William E
authors.initials: WE
authors.lastname: Dennis
authors.forename: John A
authors.initials: JA
authors.lastname: Lewis
authors.forename: Russell S
authors.initials: RS
authors.lastname: Thomas
authors.forename: Gail D
authors.initials: GD
authors.lastname: Chapman
mesh_terms: D000280:Administration, Inhalation; D000393:Air Pollutants / Q000633:toxicity*; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D001985:Bronchial Provocation Tests; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry / Q000166:cytology; D004391:Dust / Q000032:analysis; D015870:Gene Expression / Q000187:drug effects; D018737:Hand Strength; D007493:Iraq; D007830:Larynx / Q000187:drug effects / Q000473:pathology; D008168:Lung / Q000187:drug effects / Q000473:pathology / Q000502:physiology; D008297:Male; D008670:Metals / Q000032:analysis / Q000633:toxicity*; D009043:Motor Activity / Q000187:drug effects; D020411:Oligonucleotide Array Sequence Analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D012129:Respiratory Function Tests; D020545:Respiratory Mucosa / Q000187:drug effects / Q000473:pathology; D012822:Silicon Dioxide / Q000032:analysis / Q000633:toxicity*; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*; D014132:Trachea / Q000187:drug effects / Q000473:pathology
chemical_list: D000393:Air Pollutants; D004391:Dust; D008670:Metals; D014028:Tobacco Smoke Pollution; D012822:Silicon Dioxide