First hyperpolarized [2-13C]pyruvate MR studies of human brain metabolism

We developed methods for the preparation of hyperpolarized (HP) sterile [2-C-13]pyruvate to test its feasibility in first-ever human NMR studies following FDA-IND & IRB approval. Spectral results using this MR stable-isotope imaging approach demonstrated the feasibility of investigating human cerebral energy metabolism by measuring the dynamic conversion of HP [2-C-13]pyruvate to [2-C-13]lactate and [5-C-13]glutamate in the brain of four healthy volunteers. Metabolite kinetics, signal-to-noise (SNR) and area-undercurve (AUC) ratios, and calculated [2-C-13]pyruvate to [2-C-13]lactate conversion rates (k(PL)) were measured and showed similar but not identical inter-subject values. The k(PL) measurements were equivalent with prior human HP [1-C-13]pyruvate measurements. (C) 2019 Elsevier Inc. All rights reserved.