title: Inhibitory effects of anti-oxidants on apoptosis of a human polyclonal T-cell line, MT-2, induced by an asbestos, chrysotile-A.
abstract: To clarify the effects of silica and silicates on cellular features of lymphocytes, a human T-lymphotropic virus type-1-immortalized polyclonal T-cell line, MT-2, was exposed to various concentrations of chrysotile-A, an asbestos classified as silicate. MT-2 cells underwent apoptosis in a dose- and time-dependent manner. The mitochondrial apoptotic pathway was activated during chrysotile-A-induced apoptosis of MT-2 cells, because of the phosphorylation of JNK and p38, increase of BAX and release of cytochrome-c from mitochondria to cytoplasma. In addition, anti-oxidants such as hydroxyl-radical excluders and capturers of superoxide and inhibitors of superoxide production effectively reduced the size of the apoptotic fraction in MT-2 cells cultured with chrysotile-A. These results indicate that the activation of reactive oxygen species may play a central role in asbestos-induced T-cell apoptosis, and anti-oxidants may help to prevent complications of pneumoconiosis.
authors.affiliation: Department of Hygiene, Kawasaki Medical School, Kurashiki, Okayama, Japan.
authors.forename: F
authors.initials: F
authors.lastname: Hyodoh
authors.forename: A
authors.initials: A
authors.lastname: Takata-Tomokuni
authors.forename: Y
authors.initials: Y
authors.lastname: Miura
authors.forename: H
authors.initials: H
authors.lastname: Sakaguchi
authors.forename: T
authors.initials: T
authors.lastname: Hatayama
authors.forename: S
authors.initials: S
authors.lastname: Hatada
authors.forename: H
authors.initials: H
authors.lastname: Katsuyama
authors.forename: Y
authors.initials: Y
authors.lastname: Matsuo
authors.forename: T
authors.initials: T
authors.lastname: Otsuki
mesh_terms: D017209:Apoptosis / Q000187:drug effects* / Q000502:physiology; D017632:Asbestos, Serpentine / Q000009:adverse effects*; D002461:Cell Line, Transformed / Q000187:drug effects / Q000502:physiology; D004121:Dimethyl Sulfoxide / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D016166:Free Radical Scavengers / Q000494:pharmacology*; D006801:Humans; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D013481:Superoxides / Q000037:antagonists & inhibitors* / Q000378:metabolism; D013601:T-Lymphocytes / Q000187:drug effects / Q000502:physiology; D013997:Time Factors
chemical_list: D017632:Asbestos, Serpentine; D016166:Free Radical Scavengers; D013481:Superoxides; D004121:Dimethyl Sulfoxide