OLE1 reduces cadmium-induced oxidative damage in Saccharomyces cerevisiae

Abstract

Cadmium has been shown to be an important environmental pollutant. Our previous studies have shown that the regulation of OLE1 in the synthesis of unsaturated fatty acids may act as a positive feedback mechanism to help yeast cells counter the lipid peroxidation and cytoplasmic membrane damage induced by cadmium. However, the involvement of OLE1 in cadmium-induced oxidative stress is still unclear. In this study, we explored the effects of OLE1 on cadmium induced oxidative stress in yeast. Different from ascorbic acid, the overexpression of OLE1 did not affect the activities of superoxide dismutase, catalase and glutathione peroxidase. Although OLE1 overexpression induced an increase in GSH levels, the anti-oxidative mechanism of OLE1 was GSH1 independent. On the other hand, similar to ascorbic acid, OLE1 overexpression significantly reduced the levels of superoxide radical, carbonyl protein and lipid peroxidation. Additionally, overexpression of OLE1 effectively prevented cell membrane damage induced by cadmium. OLE1 could also reduce the cytotoxicities of other heavy metals stress, including copper, tri- and hexavalent chromium. Thus, our results indicate that overexpression of OLE1 reduces oxidative stress induced by cadmium possibly through the inhibition of lipid peroxidation and protection of the cytoplasmic membrane from damage in yeast cells. Furthermore, we determined that the anti-oxidative effect of OLE1 is independent of antioxidant enzymes and GSH1.