Figure 5. Metabolite profiles of metformin are the result of altered substrate utilization in the mitochondria.
A. 13C enrichment patterns that are derived from different 13C labeled fuel sources. Solid circle denotes 13C carbon while open circle denotes 12C carbon. B to D. 13C isotopologues distribution of citrate from cells treated with 13C labeled glucose, glutamine or palmitate for 6 hrs. E to G. 13C enrichment in aspartate from 13C labelled glucose, glutamine or palmitate. H to I. UTP 13C distribution in the presence of 13C labelled glucose or glutamine. 13C labelled UTP was not detected from 13C labeled palmitate. * p<0.05, ** p<0.01 Error bars obtained from SEM of n=3 independent measurements.