Abstracts of the 33rd Annual Meeting of the United Kingdom Environmental Mutagen society, 12th-14th July 2010 at the University of Derby, UK
Year: 2010
Type: conference-abstract
Abstract: Nanotechnology is without doubt a fast growing industry with major benefits in the fields of engineering, environmental remediation and healthcare.Single walled carbon nanotubes (SWCNTs) are a part of this growth and yet numerous questions regarding their genotoxicity and the mechanisms involved in such processes remain unanswered.Therefore, in this study the influence of SWCNTs of three different lengths (400-800nm, 1-3lm, 5-30lm) at a dose ranging between 1lg/ ml to 100lg/ml on oxidative stress and gene expression were studied in human bronchial epithelial cells (BEAS-2B).The 2',7'-dichlorofluorescein-diacetate (DCFH-DA) fluorometric assay revealed a concentration and time-dependent increase in reactive oxygen species (ROS) in the 1-3lm sample.The same was true for the 400-800nm sample up to 20lg/ml.Interestingly, the only significant increase in ROS was observed at the lowest doses (1lg/ml and 5lg/ml) in the 5-30lm sample possibly due to larger agglomerates sedimenting out of suspension.There was a remarkably significant decrease in these levels when 4mM antioxidant N-acetyl cysteine (NAC) was added to the reaction.These results were consistent with data obtained from oxidative damage pathway gene expression profiling by RT-PCR.Exposure to all the sub-cytotoxic doses of 1-3lm SWCNTs, lower doses of 400-800nm and lowest dose of sample 5-30lm sample resulted in 2 fold upregulation in the expression of six genes.These results were comparable to alterations seen in this study from treatments with crocidolite asbestos fibres.The up-regulated genes were; DUOX1, EPHX2, GPX2, NCF1 SEPP1, and SFTPD, which are involved in the removal of H 2 O 2 and other reactive oxygen species in cells.Similar results were seen at the lower doses in the 400-800nm sample and the lowest dose in the 5-30lm sample.These findings suggest that exposure to SWCNTs can lead to adverse cellular responses in mammalian cell lines through the activation of genes involved in the protection and possibly molecular signaling associated with oxidative stress.
Source: Mutagenesis
Language: English
Subfield: Cancer Research
Domain: Life Sciences
Open Access status: bronze
OpenAlex ID: W2986315461