Reduction and oxidation (redox) chemistry is involved in both normal and abnormal cellular function, in processes as diverse as circadian rhythms and neurotransmission. Intracellular redox is maintained by coupled reactions involving
NADPH,
glutathione (GSH), and
vitamin C, as well as their corresponding oxidized counterparts. In addition to functioning as
enzyme cofactors, these
reducing agents have a critical role in dealing with
reactive oxygen species (ROS), the toxic products of oxidative metabolism seen as culprits in aging,
neurodegenerative disease, and
ischemia/ reperfusion injury. Despite this strong relationship between redox and human disease, methods to interrogate a redox pair in vivo are limited. Here we report the development of [1-(13)C] dehydroascorbate [DHA], the oxidized form of
Vitamin C, as an endogenous redox sensor for in vivo imaging using hyperpolarized (13)C spectroscopy. In murine models, hyperpolarized [1-(13)C] DHA was rapidly converted to [1-(13)C]
vitamin C within the liver, kidneys, and brain, as well as within
tumor in a transgenic
prostate cancer mouse. This result is consistent with what has been previously described for the DHA/
Vitamin C redox pair, and points to a role for hyperpolarized [1-(13)C] DHA in characterizing the concentrations of key intracellular
reducing agents, including GSH. More broadly, these findings suggest a prognostic role for this new redox sensor in determining vulnerability of both normal and abnormal tissues to ROS.