title: Titanium dioxide nanoparticles impair lung mitochondrial function.
abstract: Titanium dioxide nanoparticles (TiO(2) NPs) are used in an increasing number of human products such as cosmetics, sunscreen, toothpaste and paints. However, there is clear evidence about effects associated to TiO(2) NPs exposure, which include lung inflammation and tumor formation and these effects are related to reactive oxygen species (ROS) formation. The ROS generation could be attributed to a mitochondrial dysfunction. Even though, it has been shown that TiO(2) NPs exposure can induce some alterations in mitochondria including cytochrome c release to cytosol, change in mitochondrial permeability and decrease of mitochondrial membrane potential (ΔΨ(m)), there is no information about the changes in mitochondrial function induced by TiO(2) NPs. We hypothesized that TiO(2) NPs effects are associated with mitochondrial dysfunction and redox unbalance. To test our hypothesis we isolated mitochondria from lung tissue of rats and exposed them to 10(g TiO(2) NPs (particle size<25nm)/mg protein for 1h. Our results showed that TiO(2) NPs decreases NADH levels and impairs ΔΨ(m) and mitochondrial function accompanied by ROS generation during mitochondrial respiration.
authors.affiliation: Laboratorio 10, Unidad de Biomedicina, Facultad de Estudios Superiores Iztacala, UNAM, 54090 Tlalnepantla, Av. de Los Barrios 1, Los Reyes Iztacala, Edo de México, Mexico.
authors.forename: Verónica
authors.initials: V
authors.lastname: Freyre-Fonseca
authors.forename: Norma Laura
authors.initials: NL
authors.lastname: Delgado-Buenrostro
authors.forename: Emma Berta
authors.initials: EB
authors.lastname: Gutiérrez-Cirlos
authors.forename: Claudia Marissa
authors.initials: CM
authors.lastname: Calderón-Torres
authors.forename: Tecilli
authors.initials: T
authors.lastname: Cabellos-Avelar
authors.forename: Yesennia
authors.initials: Y
authors.lastname: Sánchez-Pérez
authors.forename: Enrique
authors.initials: E
authors.lastname: Pinzón
authors.forename: Ismael
authors.initials: I
authors.lastname: Torres
authors.forename: Eduardo
authors.initials: E
authors.lastname: Molina-Jijón
authors.forename: Cecilia
authors.initials: C
authors.lastname: Zazueta
authors.forename: José
authors.initials: J
authors.lastname: Pedraza-Chaverri
authors.forename: Claudia María
authors.initials: CM
authors.lastname: García-Cuéllar
authors.forename: Yolanda I
authors.initials: YI
authors.lastname: Chirino
mesh_terms: D000818:Animals; D004305:Dose-Response Relationship, Drug; D008171:Lung Diseases / Q000139:chemically induced* / Q000378:metabolism; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects / Q000502:physiology; D018613:Microscopy, Confocal; D008857:Microscopy, Interference; D008928:Mitochondria / Q000187:drug effects* / Q000378:metabolism; D009243:NAD / Q000378:metabolism; D053758:Nanoparticles / Q000633:toxicity*; D010101:Oxygen Consumption / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism; D014025:Titanium / Q000378:metabolism / Q000633:toxicity*
chemical_list: D017382:Reactive Oxygen Species; D009243:NAD; C009495:titanium dioxide; D014025:Titanium