TY - JOUR T1 - Particulate air pollution affects alveolization in a juvenile mice model of asthma JF - European Respiratory Journal JO - Eur Respir J VL - 44 IS - Suppl 58 SP - P1093 AU - Mariana Veras AU - Aila Teles AU - Natália Costa AU - Gabriel Ribeiro-Junior AU - Paulo Saldiva AU - Thais Mauad Y1 - 2014/09/01 UR - http://erj.ersjournals.com/content/44/Suppl_58/P1093.abstract N2 - Asthma prevalence has increased worldwide and environmental and/or genetic factors are thought to be responsible. Effects of air pollution (AP) on the severity and symptoms are increasingly recognized. Epi and experimental data suggest that lung development could be impaired by gestational and neonatal exposures to AP. Methods: 32 BALB/c mice were injected with ovalbumin [10mg OVA + 1mg Al (OH)3] or PBS on 5th and 7th postnatal day (pnd). From 9th to 39th pnd they were exposed daily to AP ([600 µg/m³] of PM2.5) or filtered air. 4 groups were formed (n=6-9): control (CON), pollution (PM), ovalbumin (OVA), OVA+PM2.5 (OVAPM). Further, mice were challenged with nebulized OVA (3% in PBS) for 15 min/day on 9th-11th, 24th-26th, 37th-39th pnd and euthanized on 40th pnd for stereological evaluation of the lung. Volumes (V) and volume fractions were assessed by the Cavalieri principle or point counting and the number alveoli (N) were estimated by Euler number of the network of alveolar openings (physical dissectors). Result: Lung V was significantly decreased in all groups when compared to CON (p=0.001), V of alveolar septum and airways were also reduced in groups OVA and OVAPM compared to CON (p=0.03). N of alveoli was significantly reduced in PM (less 59%), OVA (less 55%) and OVAPM (less 67%) groups when compared to the CON (p=0,001). Effects of OVA seems to be greater than solely exposure to PM, however the combination of both OVA and PM exacerbates the outcome. Conclusion: Lung development is impaired in young sensitized animals and early-life exposure to AP may aggravate this effect. ER -