BACKGROUND: Pollution by particulates has consistently been associated with increased cardiovascular morbidity and mortality, but a plausible biological basis for this association is lacking. METHODS AND RESULTS: Diesel exhaust particles (DEPs) were instilled into the trachea of hamsters, and blood platelet activation, experimental thrombosis, and lung inflammation were studied. Doses of 5 to 500 micro g of DEPs per animal induced neutrophil influx into the bronchoalveolar lavage fluid with elevation of protein and histamine but without lactate dehydrogenase release. The same doses enhanced experimental arterial and venous platelet rich-thrombus formation in vivo. Blood samples taken from hamsters 30 and 60 minutes after instillation of 50 micro g of DEPs yielded accelerated aperture closure (ie, platelet activation) ex vivo, when analyzed in the Platelet Function Analyser (PFA-100). The direct addition of as little as 0.5 micro g/mL DEPs to untreated hamster blood significantly shortened closure time in vitro. CONCLUSIONS: The intratracheal instillation of DEPs leads to lung inflammation as well as a rapid activation of circulating blood platelets. The kinetics of platelet activation are consistent with the reported clinical occurrence of thrombotic complications after exposure to pollutants. Our findings, therefore, provide a plausible explanation for the increase in cardiovascular morbidity and mortality accompanying urban air pollution.
BACKGROUND: Pollution by particulates has consistently been associated with increased cardiovascular morbidity and mortality, but a plausible biological basis for this association is lacking. METHODS AND RESULTS: Diesel exhaust particles (DEPs) were instilled into the trachea of hamsters, and blood platelet activation, experimental thrombosis, and lung inflammation were studied. Doses of 5 to 500 micro g of DEPs per animal induced neutrophil influx into the bronchoalveolar lavage fluid with elevation of protein and histamine but without lactate dehydrogenase release. The same doses enhanced experimental arterial and venous platelet rich-thrombus formation in vivo. Blood samples taken from hamsters 30 and 60 minutes after instillation of 50 micro g of DEPs yielded accelerated aperture closure (ie, platelet activation) ex vivo, when analyzed in the Platelet Function Analyser (PFA-100). The direct addition of as little as 0.5 micro g/mL DEPs to untreated hamster blood significantly shortened closure time in vitro. CONCLUSIONS: The intratracheal instillation of DEPs leads to lung inflammation as well as a rapid activation of circulating blood platelets. The kinetics of platelet activation are consistent with the reported clinical occurrence of thrombotic complications after exposure to pollutants. Our findings, therefore, provide a plausible explanation for the increase in cardiovascular morbidity and mortality accompanying urban air pollution.
Authors: Anna Radomski; Paul Jurasz; David Alonso-Escolano; Magdalena Drews; Maria Morandi; Tadeusz Malinski; Marek W Radomski Journal: Br J Pharmacol Date: 2005-11 Impact factor: 8.739
Authors: Tim S Nawrot; Jan A Staessen; Robert H Fagard; Luc M Van Bortel; Harry A Struijker-Boudier Journal: Eur J Epidemiol Date: 2005 Impact factor: 8.082
Authors: Nicholas L Mills; Ken Donaldson; Paddy W Hadoke; Nicholas A Boon; William MacNee; Flemming R Cassee; Thomas Sandström; Anders Blomberg; David E Newby Journal: Nat Clin Pract Cardiovasc Med Date: 2008-11-25