Hyperpolarized 13C Ascorbates in the Anesthetized Rat Brain

David M. Wilson¹, John Kurhanewicz¹, Kayvan R. Keshari¹

The reducing agents glutathione and Vitamin C are maintained at high concentrations in the brain, and have a critical role in dealing with reactive oxygen species seen as culprits in aging, neurodegenerative disease, and ischemic injury. We have developed [1-13C] dehydroascorbate, the oxidized form of Vitamin C, as a redox sensor for in vivo imaging using hyperpolarized 13C spectroscopy. In anesthetized rats, hyperpolarized [1-13C] DHA was rapidly converted to [1-13C] Vitamin C within the brain. In contrast, hyperpolarized [1-13C] Vitamin C studies demonstrated no observable oxidation to [1-13C] DHA, with diminished signals in brain voxels consistent with limited blood-brain-barrier penetration.