Assessment of hepatic glycogen metabolism ex vivo and in vivo in mice using chemical exchange saturation transfer MRI

Despite being integral to whole body glucose homeostasis, liver glycogen remains difficult to measure non-invasively. Recent works have demonstrated the feasibility of detecting liver glycogen using CEST MRI. In this presentation we present data that builds upon this observation and investigate whether CEST can be used to monitor glycogen synthesis and breakdown in mice in real time both ex vivo in a perfused liver system, and in vivo. Treatment with hyperglycemia or glucagon resulted in increases or decreases, respectively, in the CEST MTRasym AUC over time. This demonstrates that CEST-based approaches can be used to non-invasively monitor glycogen metabolism.