Examination of Single-Walled Carbon Nanotubes Uptake and Toxicity from Dietary Exposure: Tracking Movement and Impacts in the Gastrointestinal System

Nanomaterials

Joseph H. Bisesi²  Thuy Ngo²  Satvika Ponnavolu²  Keira Liu¹  Candice M. Lavelle²  A.R.M. Nabiul Afrooz⁴  Navid B. Saleh⁴  P. Lee Ferguson¹  Nancy D. Denslow³  Tara Sabo-Attwood² 

[1] Department of Civil and Environmental Engineering, Nicholas School of the Environment, Duke University, Durham, NC 27708, USA; E-Mails:;Department of Environmental and Global Health, Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611, USA; E-Mails:;Department of Physiological Sciences, Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611, USA; E-Mail:;Department of Civil, Architectural, and Environmental Engineering, The University of Texas Austin, Austin, TX 78712, USA; E-Mails:

关键词: single-walled carbon nanotubes(SWCNTs);    fish;    near-infrared fluorescence (NIRF);    sorption;    gastrointestinal system;    gene expression;    nutrient transporters;   

DOI  :  10.3390/nano5021066

来源: mdpi

【 摘 要 】

Previous studies indicate that exposure of fish to pristine single-walled carbon nanotubes (SWCNTs) by oral gavage, causes no overt toxicity, and no appreciable absorption has been observed. However, in the environment, SWCNTs are likely to be present in dietary sources, which may result in differential impacts on uptake and biological effects. Additionally, the potential of these materials to sorb nutrients (proteins, carbohydrates, and lipids) while present in the gastrointestinal (GI) tract may lead to nutrient depletion conditions that impact processes such as growth and reproduction. To test this phenomenon, fathead minnows were fed a commercial diet either with or without SWCNTs for 96 h. Tracking and quantification of SWCNTs using near-infrared fluorescence (NIRF) imaging during feeding studies showed the presence of food does not facilitate transport of SWCNTs across the intestinal epithelia. Targeting genes shown to be responsive to nutrient depletion (peptide transporters, peptide hormones, and lipases) indicated that pept2, a peptide transporter, and cck, a peptide hormone, showed differential mRNA expression by 96 h, a response that may be indicative of nutrient limitation. The results of the current study increase our understanding of the movement of SWCNTs through the GI tract, while the changes in nutrient processing genes highlight a novel mechanism of sublethal toxicity in aquatic organisms.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.