Single-walled Carbon Nanotubes: Geno- and Cytotoxic Effects in Lung Fibroblast V79 Cells

Abstract

With the development of nanotechnology, there is a tremendous growth of the application of nanomaterials, which increases the risk of human exposure to these nanomaterials through inhalation, ingestion, and dermal penetration. Among different types of nanoparticles, single-walled carbon nanotubes (SWCNT) with extremely small size (1 nm in diameter) exhibit extraordinary properties and offer possibilities to create materials with astounding features. Since the release of nanoparticles in an enclosed environment is of great concern, a study of possible genotoxic effects is important. Our previous data showed that pharyngeal aspiration of SWCNT elicited pulmonary effects in C57BL/6 mice that was promoted by a robust, acute inflammatory reaction with early onset resulting in progressive interstitial fibrogenic response and the formation of granulomas. In the present study, the genotoxic potential of SWCNT was evaluated in vitro. The genotoxic effects of nanoparticles were examined using three different test systems: the comet assay and micronucleus (MN) test in a lung fibroblast (V79) cell line, and the Salmonella gene mutation assay in strains YG1024/YG1029. Cytotoxicity tests showed loss of viability in a concentration- and time-dependent manner after exposure of cells to SWCNT. Results from the comet assay demonstrated the induction of DNA damage after only 3 h of incubation with 96 microg/cm2 of SWCNT. The MN test indicated some but not significant micronucleus induction by SWCNT in the V79 cell line at the highest concentrations tested. With two different strains of Salmonella typhimurium, no mutations were found following SWCNT exposure.

Occupational Nanosafety Considerations for Carbon Nanotubes and Carbon Nanofibers

“…39 However, CNFs generate significant radicals and are more genotoxic than SWCNTs. 43 Sargent et al 44 reported that SWCNTs disrupt centrosomes in dividing lung epithelial cells resulting in multipolar mitosis and aneuploidy. MWCNTs have also been shown to interact with centrosomes preventing normal migration to mitotic poles and resulting in monopolar mitosis.…”

In vitro and in vivo toxicity assessment of nanoparticles

“…The effect of SW-CNTs was observed by various researchers on human cell lines, including human HEL 293 cells, HEK cells, A549 cells, human macrophage cells and human epithelial-like Hela cells [108][109][110]. In a study lung fibroblast cells were treated with CNTs to evaluate the toxicity [53]. In another study when A549 cells were exposed to SW-CNTs at 250-500 µg/ml for 72 h, it resulted in oxidative response and membrane damage, induced by inflammatory response [111].…”

“…The investigation demonstrated the induction of apoptosis measured by Annexin V/PI in HeLa cell lines treated with gold nanoparticle [52]. Single cell gel electrophoresis assay (SCGE), or comet assay, is a sensitive tool for the detection of the mutagenic potential of a test material [53]. It is used to detect single-and double-stranded DNA breaks in individual cells, both in vitro and in vivo [54,55].…”

Citotoxicidade e genotoxicidade de nanotubos de carbon

“…84 Amostras de NTCPS com comprimento de 1,3 µm induziram quebras no DNA na dose de 96 µg/cm 2 após 3 e 24 h de exposição, em células de pulmão de hamster chinês (V79). 85 Uma mistura de NTCs (contendo ~50% de NTCPS) induziu um aumento dosedependente de danos no DNA nas concentrações de 1 a 100 µg/cm 2 . 86 Também foram encontradas quebras no DNA, na dose de 25 µg/cm 2 de amostras de NTCPS e amostras de NTCPM, 75,87 outros dados detectaram indução significativa de quebras para amostras de NTCPS em concentrações ainda menores (5 e 10 µg/mL).…”

“…114,118 Entre os vários trabalhos de genotoxicidade publicados 75,85,94,[121][122][123][124] poucos têm feito uso de análises térmicas (um parâmetro importante para caracterização e recomendado pelo National Institute of Standards and Technology). Muitos trabalhos apresentam imagens de microscopia, porém essas são de baixa resolução 74,83,85,87,88,93,97 o que compromete o entendimento dos tipos de contaminantes existentes nos NTCs. Existem ainda trabalhos sem explicação detalhada do método de síntese, tratamentos de purificação, funcionalização e sem imagens das amostras estudadas.…”