Real-time 13C nuclear magnetic resonance (NMR) spectroscopy analysis of D-(1,6-13C
)glucose consumption and (3-13C)lactate production for Snu398 and HepG2 human hepatocellular carcinoma cells. (A) Selective 13C-enrichment of glucose enables detection of 13C-enriched metabolites originating exclusively from glucose metabolism. (B) Time-dependent changes in concentrations of D-(1,6-13C2)glucose and (3-13C)lactate obtained by recording NMR spectra every 4 minutes in Snu398 and HepG2 cells in the absence and presence of 10 μM Compound 1. Peak areas for 13C-1 of glucose and 13C-3 of lactate were used for measuring their concentrations. Data are means ± SD of two independent experiments.