title: Cell membrane integrity and internalization of ingested TiO(2)  nanoparticles by digestive gland cells of a terrestrial isopod.
abstract: The present study was motivated by the paucity of reports on cellular internalization of ingested titanium dioxide (TiO(2)) nanoparticles (nano-TiO(2)). The model invertebrate (Porcellio scaber, Isopoda, Crustacea) was exposed to food dosed with nano-TiO(2) containing 100, 1,000, 3,000, or 5,000 µg nano-TiO(2) per gram of food. After 14 d of exposure, the amount of Ti in the entire body was analyzed by inductively coupled plasma-mass spectrometry, and elemental analyses of tissue cross sections were performed by particle induced X-ray emission. In addition, a series of toxicological markers including feeding parameters, weight change, and survival, as well as cytotoxic effects such as digestive gland cell membrane stability, were monitored. Internalization of ingested nano-TiO(2) by the isopod's digestive gland epithelial cells was shown to depend on cell membrane integrity. Cell membranes were found to be destabilized by TiO(2) particles, and at higher extracellular concentrations of nano-TiO(2), the nanoparticles were internalized.
authors.affiliation: University of Ljubljana, Biotechnical Faculty, Department of Biology, Ljubljana, Slovenia.
authors.forename: Sara
authors.initials: S
authors.lastname: Novak
authors.forename: Damjana
authors.initials: D
authors.lastname: Drobne
authors.forename: Janez
authors.initials: J
authors.lastname: Valant
authors.forename: Živa
authors.initials: Ž
authors.lastname: Pipan-Tkalec
authors.forename: Primož
authors.initials: P
authors.lastname: Pelicon
authors.forename: Primož
authors.initials: P
authors.lastname: Vavpetič
authors.forename: Nataša
authors.initials: N
authors.lastname: Grlj
authors.forename: Ingrid
authors.initials: I
authors.lastname: Falnoga
authors.forename: Darja
authors.initials: D
authors.lastname: Mazej
authors.forename: Maja
authors.initials: M
authors.lastname: Remškar
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000187:drug effects*; D004064:Digestive System / Q000166:cytology* / Q000187:drug effects; D004435:Eating; D004847:Epithelial Cells / Q000187:drug effects; D033321:Isopoda / Q000166:cytology / Q000187:drug effects*; D053758:Nanoparticles / Q000633:toxicity*; D014025:Titanium / Q000633:toxicity*
chemical_list: C009495:titanium dioxide; D014025:Titanium