Assessment of the short-term toxicity of TiO 2 nanofiber in Sprague Dawley rats

• Published in: Environmental toxicology 2017-06, Vol.32 (6), p.1775-1783
• Main Authors: Gato, Worlanyo E, Hunter, Daniel A, Byrd, Ian C, Mays, Christopher A, Yau, Wilson, Wu, Ji
• Format: Article
• Language: English
• Subjects: Administration, Oral; Animals; Dose-Response Relationship, Drug; Gene Expression - drug effects; Genome-Wide Association Study; Immunoglobulin alpha-Chains - genetics; Male; Nanofibers - toxicity; Pneumonia - immunology; Pneumonia - virology; Rats; Rats, Sprague-Dawley; Titanium - toxicity
• ISSN: 1520-4081; 1522-7278
• DOI: 10.1002/tox.22400

Synthetic nanomaterials have many unique chemical and physical properties, mainly due to their high specific surface area and quantum confinement effect. Specifically, titanium dioxide (TiO ) nanomaterial has high stability, anticorrosive, and photocatalytic properties. However, there are concerns over adverse biological effects resulting from bioeffects. This study was to investigate adverse effects associated with acute ingestion of TiO nanofiber (TDNF). TDNF was fabricated via electrospinning method, followed by dissolution in water. Six- to seven-week-old male Sprague Dawley rats were exposed to a total of 0, 40, and 60 ppm of TDNF for 2 weeks via oral gavage. Serum total protein and weight gain during the course of this study displayed marginal concentration-dependent alterations. These findings were followed by a global gene expression analysis to identify which transcripts might be responsive to TNDF toxicity. Differentially expressed mRNA levels were dose-dependently higher in animals exposed to TNDF. The majority of the affected genes were biochemically involved in immune response and inflammation. We believe this is due to the fact that TNDF is unable to penetrate the cell and forms phagocytosis sites that trigger inflammatory and immune response. All results taken together, short-term ingestion of TNDF produced marginal effects indicative of inflammation. Finally, the broad gene expression data were validated through quantification of immunoglobulin heavy chain alpha (Igha). Igha gene was upregulated in treated groups, showing similar expression patterns to the global gene expression data.