Oxidative Damage to DNA in Adrenocortical Cells During Senescence in Culture
Our experiments on the effects of oxidative damage on the functions of adrenocortical cells in culture were initiated by the finding that the loss of activity of cytochrome P-450 enzymes in cultured bovine adrenocortical cells incubated with steroid pseudosubstrates involved oxidative damage.1 Oxidative damage potentially occurs at a higher rate in cell culture than in vivo. Cultured cells are exposed to several potentially damaging adventitious oxidants under standard culture conditions, as well as oxidants from intracellular metabolic. processes.2 Moreover, we showed that cultured bovine adrenocortical cells suffer from a combined deficiency of vitamin E and selenium. The deficiency of these biological antioxidants in culture was observed as the ability of low concentrations of either nutrient to prevent the toxicity of the aminotransferase inhibitor, aminooxyacetate, and of an organic peroxide, cumene hydroperoxide.3,4 The two nutrients must be considered together since to a large extent the spectra of their biological activities overlap.5 Thus, it appeared worthwhile to investigate the possible role of oxidative damage in senescence of bovine adrenocortical cells in culture.
KeywordsOxidative Damage Down Syndrome Long Terminal Repeat Sister Chromatid Exchange Cloning Efficiency
Unable to display preview. Download preview PDF.
- 5.A.L. Tappel, Measurement of and protection from in vivo lipid peroxidation, in: ‘Free Radicals in Biology,’ Vol. 4, W.A. Pryor, eds., Academic Press, New York, (1980).Google Scholar
- 11.A.C.M. Filho, M.E. Hoffmann, and R. Meneghini, Cell killing and DNA damage by hydrogen peroxide are mediated by intracellular iron, Biochem. J. 218:273 (1984).Google Scholar
- 27.Y. Groner, J. Lieman-Hurwitz, N. Dafni, L. Sherman, D. Levanon, Y. Bernstein, E. Danciger, and O. Elroy-Stein, Molecular structure and expression of the gene locus on chromosome 21 encoding the Cu/Zn superoxide dismutase and its relevance to Down syndrome, Ann. N.Y. Acad. Sci. 450:133 (1985).PubMedCrossRefGoogle Scholar