Ambient particulate air pollution from vehicles promotes lipid peroxidation and inflammatory responses in rat lung.
Oxidative stress plays a major role in the pathogenesis of particle-dependent lung injury. Ambient particle levels from vehicles have not been previously shown to cause oxidative stress to the lungs. The present study was conducted to a) determine whether short-term exposure to ambient levels of particulate air pollution from vehicles elicits inflammatory responses and lipid peroxidation in rat lungs, and b) determine if intermittent short-term exposures (every 4 days) induce some degree of tolerance. Three-month-old male Wistar rats were exposed to ambient particulate matter (PM) from vehicles (N = 30) for 6 or 20 continuous hours, or for intermittent (5 h) periods during 20 h for 4 consecutive days or to filtered air (PM <10 microm; N = 30). Rats continuously breathing polluted air for 20 h (P-20) showed a significant increase in the total number of leukocytes in bronchoalveolar lavage compared to control (C-20: 2.61 x 105 +/- 0.51;P-20: 5.01 x 105 +/- 0.81; P < 0.05) and in lipid peroxidation ([MDA] nmol/mg protein: C-20: 0.148 +/- 0.01; P-20: 0.226 +/- 0.02; P < 0.05). Shorter exposure (6 h) and intermittent 5-h exposures over a period of 4 days did not cause significant changes in leukocytes. Lipid damage resulting from 20-h exposure to particulate air pollution did not cause a significant increase in lung water content. These data suggest oxidative stress as one of the mechanisms responsible for the acute adverse respiratory effects of particles, and suggest that short-term inhalation of ambient particulate air pollution from street with high automobile traffic represents a biological hazard.
Pereira
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CE
Curso de Pós-graduação em Ciências Médicas e Laboratório de Estresse Oxidativo e Poluição Atmosférica, Fundação Faculdade Federal de Ciências Médicas de Porto Alegre, Porto Alegre, RS, Brasil.
Heck
T G
TG
Saldiva
P H N
PH
Rhoden
C R
CR
D000208:Acute Disease; D000393:Air Pollutants / Q000633:toxicity*; D000818:Animals; D007249:Inflammation / Q000139:chemically induced*; D015227:Lipid Peroxidation / Q000187:drug effects*; D008168:Lung / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D008297:Male; D018384:Oxidative Stress / Q000187:drug effects; D052638:Particulate Matter / Q000633:toxicity*; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors; D001335:Vehicle Emissions / Q000633:toxicity*
D000393:Air Pollutants; D052638:Particulate Matter; D001335:Vehicle Emissions