FN1 and Hyperglycemia: Levels of citrate that correspond to activity of the tricarboxylic acid (TCA) cycle increased with rising glucose levels when the cells were grown on collagen but were relatively decreased during hyperglycaemia-induced EMT in the cells grown on fibronectin when compared with cells grown on collagen thereby confirming the more glycolytic phenotype of these cells when exposed to fibronectin (Fig. 3f).