Marie Allen Schroeder1, Helen J. Atherton1, Lisa C. Heather1, Julian L. Griffin2, Kieran Clarke1, George K. Radda1, Damian J. Tyler1
1Physiology, University of Oxford, Oxford, Oxfordshire, UK; 2Biochemistry, University of Cambridge, Cambridge, Cambridgeshire, UK
Hyperpolarized 13C MR can effectively report on in vivo alterations to metabolism. However, the technique has yet to provide information regarding mechanisms of metabolic regulation. This study has demonstrated that by strategically manipulating systemic metabolism, via co-infusion of hyperpolarized [1-13C]pyruvate with other important metabolites, the nature of metabolic regulation can be determined non-invasively. We used hyperpolarized MR to distinguish two distinct mechanisms regulating in vivo flux through the enzyme pyruvate dehydrogenase via co-infusion of [1-13C]pyruvate with malate. Thus demonstrating that this non-invasive technique may be useful to indirectly follow complex mechanisms of metabolic regulation, in normal and diseased hearts.