Hydroxyl radical mediated DNA base modification by manmade mineral fibres.

Hydroxyl radical mediated DNA base modification by manmade mineral fibres.

Manmade mineral fibres (MMMFs) were examined for their ability to hydroxylate 2-deoxyguanosine (dG) to 8-hydroxydeoxyguanosine (8-OH-dG), a reaction that is mediated by hydroxyl radicals. It appeared that (1) catalase and the hydroxyl radical scavengers, dimethylsulphoxide and sodium benzoate, inhibited the hydroxylation, whereas Fe2+ and H2O2 potentiated it; (2) pretreatment of MMMFs with the ...

Role of manmade mineral fibres in the causation of cancer.

Dimethyl sulfoxide prevents DNA nicking mediated by ionizing radiation or iron/hydrogen peroxide-generated hydroxyl radical.

Eighty percent of the single-strand DNA breaks induced by gamma-irradiation were prevented by the hydroxyl radical (.OH) scavenger dimethyl sulfoxide (Me2SO); CH4 was generated in the process as a product of the interaction of .OH and Me2SO. In contrast, Me2SO completely blocked DNA nicking by an iron/H2O2 system which produces .OH but smaller amounts of CH4 from Me2SO. Because Me2SO prevented ...

Hydroxyl radical-mediated modification of proteins as probes for structural proteomics.

an electron from a disulfide bond, giving rise to a disulfide radical cation (RSSR)•+,291 which is stabilized by electron delocalization. Heterolysis of (RSSR)•+ produces a thiyl radical RS• and a sulfenium cation RS+;281 RS+ may be neutralized by OHto form sulfenic acid or may absorb an O2 to form an sulfonium cation RSO2, which combines with an OHto become sulfonic acid RSO3H. The thiyl radic...

Mineral fibres: correlation between oxidising surface activity and DNA base hydroxylation.

In relation to their potential genotoxic properties, the ability of inorganic particles to induce activated species of oxygen with strong oxidative properties can be studied by various methods. In this study the oxidative surface properties of 10 different natural and synthetic mineral fibres were investigated by: (1) an electron paramagnetic resonance technique in which formate was used to tra...