title: Mesoporous silica nanoparticles enhance MTT formazan exocytosis in HeLa cells and astrocytes.
abstract: We report on the observation that mesoporous silica nanoparticles (MSNs), after being endocytosed, interfere with the MTT test in HeLa cells and astrocytes by accelerating the exocytosis of formazan crystals. The stimulation of MTT formazan exocytosis is probably related to perturbation of intracellular vesicle trafficking by MSN uptake as revealed by experiments in presence of chloroquine and genistein. Similar effect has been previously observed with a number of chemicals, especially with neurotoxic beta amyloid peptides, but not with nanoparticles. We showed also that MTT reduction test gives an overestimation of the cytotoxicity of mesoporous silica nanoparticles compared to other tests such as LDH activity, WST-1 test and flow cytometry. These findings show that MTT assay should not be used for the study of MSN toxicity, and that perturbation of intracellular trafficking has to be taken into account in evaluating biocompatibility of MSNs.
authors.affiliation: CNRS, Centre de Recherche sur la Matière Divisée, UMR6619, Orléans, France.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Fisichella
authors.forename: Hinda
authors.initials: H
authors.lastname: Dabboue
authors.forename: Sanjib
authors.initials: S
authors.lastname: Bhattacharyya
authors.forename: Marie-Louise
authors.initials: ML
authors.lastname: Saboungi
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Salvetat
authors.forename: Tobias
authors.initials: T
authors.lastname: Hevor
authors.forename: Martine
authors.initials: M
authors.lastname: Guerin
mesh_terms: D001253:Astrocytes / Q000187:drug effects* / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects; D005089:Exocytosis / Q000187:drug effects*; D005562:Formazans / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D053758:Nanoparticles / Q000633:toxicity*; D012822:Silicon Dioxide / Q000633:toxicity*; D013778:Tetrazolium Salts / Q000378:metabolism*
chemical_list: D005562:Formazans; D013778:Tetrazolium Salts; C079782:MTT formazan; D012822:Silicon Dioxide