Abstract
Increased glucose uptake and aerobic glycolysis are striking features of many cancers. These features have led to many techniques for screening and diagnosis, but many are expensive, less feasible or have harmful side-effects. Here, we report a sensitive 1H/2H NMR method to measure the kinetics of lactate isotopomer and HDO production using a deuterated tracer. To test this hypothesis, HUH-7 hepatocellular carcinoma and AML12 normal hepatocytes were incubated with [2H7]glucose. 1H/2H NMR data were recorded for cell media as a function of incubation time. The efflux rate of lactate-CH3, lactate-CH2D and lactate-CHD2 was calculated as 0.0033, 0.0071, and 0.0.012 µmol/106cells/min respectively. Differential production of lactate isotopomers was due to deuterium loss during glycolysis. Glucose uptake and HDO production by HUH-7 cells showed a strong correlation, indicating that monitoring the HDO production could be a diagnostic feature in cancers. Deuterium mass balance of [2H7]glucose uptake to 2H-lactate and HDO production is quantitatively matched, suggesting increasing HDO signal could be used to diagnose Warburg (cancer) metabolism. Measuring the kinetics of lactate isotopomer and HDO production by 1H and 2H MR respectively are highly sensitive. Increased T1 of 2H-lactate isotopomers indicates inversion/saturation recovery methods may be a simple means of generating metabolism-based contrast.