Probing carbohydrate metabolism using hyperpolarized 13C‐labeled molecules

Glycolysis is a fundamental metabolic process in all organisms. Anomalies in glucose metabolism are linked to various pathological conditions. In particular, elevated aerobic glycolysis is a characteristic feature of rapidly growing cells. Glycolysis and the closely related pentose phosphate pathway can be monitored in real time by hyperpolarized ¹³C‐labeled metabolic substrates such as ¹³C‐enriched, deuterated D‐glucose derivatives, 2‐¹³C]‐D‐fructose, 2‐¹³C] dihydroxyacetone, 1‐¹³C]‐D‐glycerate, 1‐¹³C]‐D‐glucono‐δ‐lactone and 1‐¹³C] pyruvate in healthy and diseased tissues. Elevated glycolysis in tumors (the Warburg effect) was also successfully imaged using hyperpolarized U‐¹³C₆, U‐²H₇]‐D‐glucose, while the size of the preexisting lactate pool can be measured by ¹³C MRS and/or MRI with hyperpolarized 1‐¹³C]pyruvate. This review summarizes the application of various hyperpolarized ¹³C‐labeled metabolites to the real‐time monitoring of glycolysis and related metabolic processes in normal and diseased tissues.