Airway inflammatory response to diesel exhaust generated at urban cycle running conditions.
BACKGROUND
Diesel exhaust (DE) is an important component in traffic-related air pollution, associated with adverse health effects. DE generated at idling has been demonstrated to induce inflammation in human airways, in terms of inflammatory cell recruitment, enhanced expression of vascular endothelial adhesion molecules, cytokines, mitogen-activated protein kinases, and transcription factors in the bronchial epithelium.


OBJECTIVE
This study aimed to investigate airway inflammatory responses in healthy subjects exposed to DE generated during transient speed and engine load under the urban part of the European Transient Cycle.


METHODS
Fifteen healthy subjects were exposed to DE at an average particulate matter concentration of 270 µg/m(3) and filtered air for 1 h. Bronchoscopy with endobronchial mucosal biopsy sampling and airway lavage was performed 6 h postexposure.


RESULTS
Compared with filtered air, DE exposure caused an increased expression of the vascular endothelial adhesion molecules P-selectin and vascular cell adhesion molecule-1 (P  =  0.036 and P  =  0.030, respectively) in bronchial mucosal biopsies, together with increased numbers of bronchoalveolar lavage eosinophils (P  =  0.017).


CONCLUSIONS
DE generated under urban running conditions increased bronchial adhesion molecule expressions, together with the novel finding of bronchoalveolar eosinophilia, which has not been shown after exposure to DE at idling. Variations in airway inflammatory response to DE generated under diverse running condition may be related to differences in exhaust composition.
Department of Public Health and Clinical Medicine, Respiratory Medicine, Umeå University, Umeå, Sweden.
Maria
M
Sehlstedt
Annelie F
AF
Behndig
Christoffer
C
Boman
Anders
A
Blomberg
Thomas
T
Sandström
Jamshid
J
Pourazar
D000328:Adult; D000393:Air Pollutants / Q000009:adverse effects; D001642:Bicycling; D005260:Female; D006801:Humans; D018836:Inflammation Mediators / Q000633:toxicity*; D019570:Inhalation Exposure / Q000009:adverse effects*; D008168:Lung / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D008297:Male; D052638:Particulate Matter / Q000009:adverse effects; D012420:Running; D014504:Urban Health; D001335:Vehicle Emissions / Q000633:toxicity*; D055815:Young Adult
D000393:Air Pollutants; D018836:Inflammation Mediators; D052638:Particulate Matter; D001335:Vehicle Emissions