Carolina RodrÃguez-Ibarra
Universidad Nacional Autónoma de México, 54090 Tlalnepantla de Baz, Méx.
Title: Titanium dioxide food grade induces reactive oxygen species production and cell cycle arrest in colorectal cancer cells
Biography
Biography: Carolina RodrÃguez-Ibarra
Abstract
Titanium dioxide food grade (E171) is an additive commonly used as a whitening agent in food and as excipient in toothpaste and pharmaceuticals at quantum satis in the European Union, meaning there is no specific quantity restriction. Although E171 has been considered safe, inhalation of industrial titanium dioxide has been classified as a possible carcinogen, which has raised concerns about possible adverse outcomes when ingested. Oral E171 administration exacerbates tumour formation in murine models of colorectal cancer. However, cellular mechanisms related to carcinogenesis have not been fully investigated. The aim of this work was to investigate cellular mechanisms of toxicity induced by an acute E171 exposure in colon epithelial cells and also analyze if those alterations are permanent or can be reversed. Acute E171 exposure induced an increase in cell granularity and reactive oxygen species generation, which were not accumulative but were lasting for at least 2 days, however alterations in cell cycle distribution observed during the acute exposure were reverted after 2 days. Finally, no internalization of particles in the nuclei was detected but only periniclear localization.