Lipid droplets alleviate cadmium induced cytotoxicity in Saccharomyces cerevisiae

Cadmium (Cd) induces oxidative stress that generates reactive oxygen species (ROS) and increased lipid accumulation. However, very little is known about the role of oxidative stress in triacylglycerol (TAG) accumulation. TAG accumulation is deleterious to health and may result in obesity-associated metabolic syndrome. Hence TAG accumulation plays an important role in Cd induced cytotoxicity. The exposure of Wild-type (WT) cells to Cd, resulted in TAG accumulation and also enhanced viability when compared to TAG mutants (dga1Δ, lro1Δ and are2Δ). The inhibition of lipolysis also increased the tolerance of the cells to Cd. Fluorescence microscopy observations using acridine orange and DHR123 staining demonstrated that the TAG deficient mutants showed enhanced cell death and ROS production. The over expression of DGA1 and LRO1 rescued the Cd induced cytotoxicity by enhancing the formation of LDs. Results of this study revealed the possible metabolic link between LDs and oxidative stress in S. cerevisiae.