title: Microglial cells (BV-2) internalize titanium dioxide (TiO2) nanoparticles: toxicity and cellular responses.
abstract: Because of their whitening and photocatalytic effects, titanium dioxide nanoparticles (TiO2-NPs) are widely used in daily life. These NPs can be found in paints, plastics, papers, sunscreens, foods, medicines (pills), toothpastes, and cosmetics. However, the biological effect of TiO2-NPs on the human body, especially on the central nervous system, is still unclear. Many studies have demonstrated that the brain is one of the target organs in acute or chronic TiO2-NPs toxicity. The present study aimed to investigate the effect of TiO2-NPs at different concentrations (0.1 to 200 μg/mL) on murine microglial cells (BV-2) to assess their activity on cell growth and viability, as well as their neurotoxicity. Different parameters were measured: cell viability, cell proliferation and DNA content (SubG1 peak), mitochondrial depolarization, overproduction of reactive oxygen species (especially superoxide anions), and ultrastructural changes. Results showed that TiO2-NPs induced some cytotoxic effects with a slight inhibition of cell growth. Thus, at high concentrations, TiO2-NPs were not only able to inhibit cell adhesion but also enhanced cytoplasmic membrane permeability to propidium iodide associated with a loss of mitochondrial transmembrane potential and an overproduction of superoxide anions. No induction of apoptosis based on the presence of a SubG1 peak was detected. The microscopic observations also indicated that small groups of nanosized particles and micron-sized aggregates were engulfed by the BV-2 cells and sequestered as intracytoplasmic aggregates after 24-h exposure to TiO2-NPs. Altogether, our data show that the accumulation TiO2-NPs in microglial BV-2 cells favors mitochondrial dysfunctions and oxidative stress.
authors: Laboratoire de Physiologie Intégrée, Faculté des Sciences de Bizerte, 7021, Jarzouna, Tunisia. rihanaima@yahoo.fr.|Equipe "Biochimie du Peroxysome, Inflammation et Métabolisme Lipidique" (EA 7270), Faculté des Sciences, Université de Bourgogne Franche Comté/INSERM, 21000, Dijon, France. rihanaima@yahoo.fr.
authors: Naima
authors: http://orcid.org/0000-0002-1270-3040
authors: N
authors: Rihane
authors: Equipe "Biochimie du Peroxysome, Inflammation et Métabolisme Lipidique" (EA 7270), Faculté des Sciences, Université de Bourgogne Franche Comté/INSERM, 21000, Dijon, France.
authors: Thomas
authors: T
authors: Nury
authors: Laboratoire de Physiologie Intégrée, Faculté des Sciences de Bizerte, 7021, Jarzouna, Tunisia.
authors: Imen
authors: I
authors: M'rad
authors: College of Sciences, Department of Physics, Al Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh, 11623, Saudi Arabia.
authors: Lassaad
authors: L
authors: El Mir
authors: Laboratoire de Physiologie Intégrée, Faculté des Sciences de Bizerte, 7021, Jarzouna, Tunisia.
authors: Mohsen
authors: M
authors: Sakly
authors: Laboratoire de Physiologie Intégrée, Faculté des Sciences de Bizerte, 7021, Jarzouna, Tunisia.
authors: Salem
authors: S
authors: Amara
authors: Equipe "Biochimie du Peroxysome, Inflammation et Métabolisme Lipidique" (EA 7270), Faculté des Sciences, Université de Bourgogne Franche Comté/INSERM, 21000, Dijon, France.
authors: Gérard
authors: G
authors: Lizard
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002448:Cell Adhesion; D002453:Cell Cycle / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D048430:Cell Shape; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D053768:Metal Nanoparticles / Q000737:chemistry / Q000633:toxicity*; D051379:Mice; D017628:Microglia / Q000187:drug effects / Q000502:physiology*; D018384:Oxidative Stress / Q000187:drug effects; D010316:Particle Size; D017382:Reactive Oxygen Species / Q000378:metabolism; D014025:Titanium / Q000737:chemistry / Q000378:metabolism* / Q000633:toxicity
chemical_list: D017382:Reactive Oxygen Species; C009495:titanium dioxide; D014025:Titanium
keywords: BV-2 cells; Neurotoxicity; Oxidative stress; Titanium dioxide nanoparticles