Metabolism mapping via Deuterium Metabolic Imaging

While current widely used metabolic imaging techniques, such positron emission tomography (PET) using radioactive glucose 2-¹⁸F-fluoro-2-deoxy-d-glucose (¹⁸FDG) can provide much information on i.e. glucose uptake, they do not inform on downstream metabolism. The ability to monitor tumor metabolism during progression would be of great benefit to the clinic. Researchers at Yale University School of Medicine have implemented a technique called deuterium metabolic imaging (DMI), which uses deuterium-labeled substrates to track metabolic processes in vivo using magnetic resonance imaging (MRI). DMI allows following the conversion of these labeled molecules through different metabolic pathways in the body over time and enables the 3D mapping of metabolic activity. These maps enable spatial visualization of the ratio of lactate to Glx, and therefore the Warburg effect, a hallmark of cancer metabolism, where cancer cells rely on anaerobic glycolysis even in the presence of sufficient oxygen supply. It involves an increased glucose uptake as well as increased lactate production.

Amongst other applications, the authors demonstrated the potential of DMI by mapping metabolism in a rat glioma model, where significant metabolic differences of [6,6′- ²H₂] glucose and [²H₃] acetate between normal brain and tumor tissue were visualized.

The Ultra-high Field Advantage

Ultra-high field MRI has the benefit of increased signal-to-noise (SNR) gain. This is particularly true for imaging of X-nuclei with low gyromagnetic ratios, quadruple moments, and low abundances. The ²H imaging of DMI in this study was made possible with the use of an 11.7 MRI instrument. Application of such ultra-high fields enables the establishment of novel methods that help to better understand the mechanisms of progression of tumors and to find better treatments for cancer.

Read the full paper here.

Henk M. De Feyter et al., Deuterium metabolic imaging (DMI) for MRI-based 3D mapping of metabolism in vivo.Sci. Adv.4,eaat7314(2018). DOI:10.1126/sciadv.aat7314