Lung Damage Caused By Nano-alumina

Objective:To investigate the damage、inflammation and oxidative stress induced by the nano-alumina particles on the lung tissue.To research the toxicity and damage in the cells of RAW264.7.To explore the mechanism of lung injury induced by the nano-alumina particles.Methods:Scanning electron microscopy, transmission electron microscopy, BET surface area et al was used to analysis the characterized of nano-alumina particles. Intratracheal instillation the suspension of nano-alumina particles (350mg/kg) in the lungs, after intratracheal instillation3d、28d.To detecte the distribution and oxidative stress parameters (MDA, SOD, CAT, GSH-Px) and BALF biochemical indicators in the lung tissue,the RAW267.4cells were observed by MTT assay, neutral red phagocytosis to assay macrophage phagocytic function. To detected the intracellular changes in oxidative stress parameters(MDA,SOD,GSH).Results:(1)A single particle size measured by nano-alumina particles was15±5nm,a specific surface area of200.4m2/g,which was a crystalline phase.(2)3d,28d group,the content of AL in lung tissues were (4898.43±220.84) ug/g,(2130±320.84) ug/g,compared with the saline group were significantly different.(3) After intratracheal instillation3d、28d, compared with the saline group, MDA levels were significantly increased in high dose group, SOD and GSH-Px activity was significantly lower (P<0.05).(4)After exposure3d,28d,the macrophages and neutrophils proportional has changed in the medium and high dose groups, low, medium and high-dose group compared with the saline group has increased in the activity of LDH and ACP (P<0.05).In the high-dose group AKP activity increased significantly compared with the saline group (P<0.05).(5)With increasing dose, the macrophage phagocytosis rate decreased in each dose-group and there was a dose-response relationship. After exposured24hours,the DNA with sodium group compared with the saline group was significantly decreased in cell viability in the high-dose group (P<0.05). Conclusion:Nano-alumina particles can cause structural damage、inflammation and oxidative stress in lung tissue. After the nano-alumina intratracheal instillationthe in lungs,can cause damage to the macrophages, which may be one of the main mechanisms cause lung injury.