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Air pollution impairs recovery and tissue remodeling in a murine model of acute lung injury.

ABSTRACT: Evidence regarding the impact of air pollution on acute respiratory distress syndrome (ARDS) is limited, and most studies focus on ARDS onset. Our study aimed to evaluate whether exposure to fine particulate matter interferes with lung recovery and remodeling in a murine model of acute lung injury. Forty-eight mice received nebulized LPS or the vehicle (controls). Blood, BALF, lungs and spleen were collected after 5 weeks of exposure to either PM2.5 (PM and LPS?+?PM group) or filtered air (control and LPS5w groups). Inflammatory cells and cytokines were assessed in the blood, BALF, lungs and spleen. Stereological analyses and remodeling assessments were performed by histology. The LPS?+?PM group showed increased BALF leukocytes, characterized by increased macrophages, increased IL-1? and IL-6 levels, anemia and thrombocytopenia. Moreover, we also observed septal thickening, decreased alveolar air space total volume and, septa surface density. Finally, regarding tissue remodeling, we observed elastosis of the lung parenchyma, and unlike in the LPS5w group, we did not observe fibrosis in the LPS?+?PM group. In conclusion, the delayed inflammation resolution due to subchronic exposure to PM2.5 could be influenced by low systemic and local lymphocyte counts, which lead to impaired lung injury recovery and tissue remodeling.

SUBMITTER: de Souza Xavier Costa N

PROVIDER: S-EPMC7499199 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Air pollution impairs recovery and tissue remodeling in a murine model of acute lung injury.

de Souza Xavier Costa Natália N Ribeiro Júnior Gabriel G Dos Santos Alemany Adair Aparecida AA Belotti Luciano L Schalch Alexandre Santos AS Cavalcante Marcela Frota MF Ribeiro Susan S Veras Mariana Matera MM Kallás Esper Georges EG Saldiva Paulo Hilário Nascimento PHN Dolhnikoff Marisa M Ferraz da Silva Luiz Fernando LF

Scientific reports 20200917 1

Evidence regarding the impact of air pollution on acute respiratory distress syndrome (ARDS) is limited, and most studies focus on ARDS onset. Our study aimed to evaluate whether exposure to fine particulate matter interferes with lung recovery and remodeling in a murine model of acute lung injury. Forty-eight mice received nebulized LPS or the vehicle (controls). Blood, BALF, lungs and spleen were collected after 5 weeks of exposure to either PM<sub>2.5</sub> (PM and LPS + PM group) or filtered ...[more]

PMID: 32943719

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Air pollution impairs recovery and tissue remodeling in a murine model of acute lung injury.

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Air pollution impairs recovery and tissue remodeling in a murine model of acute lung injury.

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