Carbon nanotubes induce inflammation but decrease the production of reactive oxygen species in lung.
With the rapid spread of carbon nanotubes (CNTs) applications, the respiratory toxicity of these compounds has attracted the attention of many scientists. Several studies have reported that after lung administration, CNTs could induce granuloma, fibrosis, or inflammation. By comparison with the mechanisms involved with other toxic particles such as asbestos, this effect could be attributed to an increase of oxidative stress. The aim of the present work was to test this hypothesis in vivo. Mice were intranasally instilled with 1.5mg/kg of double walled carbon nanotubes (DWCNTs). Six, 24, or 48h after administration, inflammation and localisation of DWCNTs in lungs were microscopically observed. Local oxidative perturbations were investigated using ESR spin trapping experiments, and systemic inflammation was assessed by measuring the plasma concentration of cytokines TNF-alpha, IL-1alpha, IL-1beta, IL-6, IGF-1, Leptin, G-CSF, and VEGF. Examination of lungs and the elevation of proinflammatory cytokines in the plasma (Leptin and IL-6 at 6h) confirmed the induction of an inflammatory reaction. This inflammatory reaction was accompanied by a decrease in the local oxidative stress. This effect could be attributed to the scavenger capability of pure CNTs.
Crouzier
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Unité BCM, Institut de Recherches Biomédicale des Armées/Antenne CRSSA, 24, avenue des maquis du Grésivaudan, BP 87-38 702 La Tronche Cedex, France. david.crouzier@wanadoo.fr
Follot
S
S
Gentilhomme
E
E
Flahaut
E
E
Arnaud
R
R
Dabouis
V
V
Castellarin
C
C
Debouzy
J C
JC
D000818:Animals; D002244:Carbon / Q000494:pharmacology; D016207:Cytokines / Q000097:blood*; D016179:Granulocyte Colony-Stimulating Factor / Q000097:blood; D007249:Inflammation / Q000139:chemically induced*; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D015850:Interleukin-6 / Q000097:blood; D008168:Lung / Q000187:drug effects*; D008297:Male; D051379:Mice; D037742:Nanotubes, Carbon / Q000633:toxicity*; D010084:Oxidation-Reduction; D018384:Oxidative Stress / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000378:metabolism*; D019097:Spin Trapping / Q000379:methods; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
D016207:Cytokines; D015850:Interleukin-6; D037742:Nanotubes, Carbon; D017382:Reactive Oxygen Species; D014409:Tumor Necrosis Factor-alpha; D016179:Granulocyte Colony-Stimulating Factor; D007334:Insulin-Like Growth Factor I; D002244:Carbon