The glucose/galactose assay (often referred to as the glu/gal assay) has been used for over a decade for assessing mitochondrial toxicity in vitro. The method simply compares the relative cytotoxicity of cells grown in two different medias; one containing glucose in which the cells will derive most of their energy from glycolysis, and the other containing galactose which increases the cells’ reliance on mitochondrial oxidative phosphorylation, and as such their susceptibility to mitochondrial toxicants.
A more recent approach utilises advancements in automated miniature oxygen and carbon dioxide sensing probes (the Seahorse Extracellular Flux Analyzer). This technique measures oxygen consumption, extracellular acidification rate and with selective inhibitors measures reserve capacity of mitochondria, allowing sensitive measurement of mitochondrial dysfunction.
Research at Cyprotex has focused on assessing the performance of these different in vitro approaches to predict mitochondrial toxicity. In the video below, Senior Research Scientist Julie Eakins, who is an expert in mitochondrial biology, provides an overview of the role of mitochondria in energy production, describes the different methods for measuring mitochondrial dysfunction in vitro, and presents a comparison of the performance of these assays both individually and as a combined approach.
Request a reprint of our recent publication on mitochondrial toxicity.