We investigated the damage caused by oxidative stress using the yeast Saccharomyces cerevisiae as a model biological system. After inducing oxidative stress with menadione, we were able to evaluate the extent of cellular oxidative stress by utilizing 2',7'-dichlorofluorescein diacetate (DCFH-DA) as a marker of the presence of reactive oxygen species. Cells were grown on different carbon sources in order to compare fermentative and oxidative metabolism. Under these conditions we evaluated the effectiveness of idebenone (2,3-dimethoxy-5-methyl-6-(10- hydroxydecyl)-1,4-benzoquinone) as a molecule that could relieve menadione-induced growth inhibition in Saccharomyces cerevisiae.

The aim of this work was to study the effect of the drug idebenone on the growth of a strain of Saccharomyces cerevisiae yeast and its respiratory-deficient mutant (rho(0)). We took this yeast as a model system of the interaction of the drug with mammalian cells. The effect of idebenone was evaluated in rich and minimal media. In the S288c strain, idebenone exerted a growth inhibitory effect in concentrations higher than 50 microM in media containing a carbon source consumed at mitochondrial level. In conditions of low oxygen supply, idebenone allows yeast to keep a cellular yielding comparable with conditions of normal oxygen supply. Also, the presence of idebenone in the growth media increased by 50% the fluorescence signal of rhodamine 123, indicating a higher mitochondrial membrane potential. The results could explain the effect of idebenone in the treatment of diseases in which oxygen deficiency alters the energetic metabolism of the cell.

We investigated the damage caused by oxidative stress using the yeast Saccharomyces cerevisiae as a model biological system. After inducing oxidative stress with menadione, we were able to evaluate the extent of cellular oxidative stress by utilizing 2',7'-dichlorofluorescein diacetate (DCFH-DA) as a marker of the presence of reactive oxygen species. Cells were grown on different carbon sources in order to compare fermentative and oxidative metabolism. Under these conditions we evaluated the effectiveness of idebenone (2,3-dimethoxy-5-methyl-6-(10- hydroxydecyl)-1,4-benzoquinone) as a molecule that could relieve menadione-induced growth inhibition in Saccharomyces cerevisiae.

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