Ja. Woods et al., beta-carotene enhances hydrogen peroxide-induced DNA damage in human hepatocellular HepG2 Cells, FEBS LETTER, 449(2-3), 1999, pp. 255-258
In this study, the alkaline version of the comet assay has been used to det
ermine the effect of beta-carotene supplementation (10 mu M) on peroxide-in
itiated free radical-mediated DNA damage in human HepG2 hepatoma cells. In
supplemented cells, beta-carotene failed to afford any protection against h
ydrogen peroxide-induced DNA strand breaks. Indeed, levels of strand breaks
in supplemented cells were significantly higher than in cells exposed to h
ydrogen peroxide alone, especially after a long incubation period. In contr
ast, beta-carotene afforded significant levels of protection against DNA st
rand breaks when cells were treated with tert-butyl hydroperoxide, In this
case, the level of protection increased as supplementation continued. (C) 1
999 Federation of European Biochemical Societies.