The (13)C hyperpolarized pyruvate generated by ParaHydrogen detects the response of the heart to altered metabolism in real time

Many imaging methods have been proposed to act as surrogate markers of organ damage, yet for many candidates the essential biomarkers characteristics of the injured organ have not yet been described. Hyperpolarized [1-(13)C]pyruvate allows real time monitoring of metabolism in vivo. ParaHydrogen Induced Polarization (PHIP) is a portable, cost effective technique able to generate (13)C MR hyperpolarized molecules within seconds. The introduction of the Side Arm Hydrogenation (SAH) strategy offered a way to widen the field of PHIP generated systems and to make this approach competitive with the currently applied dissolution-DNP (Dynamic Nuclear Polarization) method. Herein, we describe the first in vivo metabolic imaging study using the PHIP-SAH hyperpolarized [1-(13)C]pyruvate. In vivo maps of pyruvate and of its metabolic product lactate have been acquired on a 1 T MRI scanner. By comparing pyruvate/lactate (13)C label exchange rate in a mouse model of dilated cardiomyopathy, it has been found that the metabolic dysfunction occurring in the cardiac muscle of the diseased mice can be detected well before the disease can be assessed by echocardiographic investigations.