Peter Edward Thelwall1, Nicholas E. Simpson2, Zahid N. Rabbani3, Daniel Clark2, Roxana Pourdeyhimi4, Jeffrey M. Macdonald4, Stephen J. Blackband2, Michael P. Gamcsik4
1Newcastle Magnetic Resonance Centre, Newcastle University, Newcastle upon Tyne, Tyne & Wear, United Kingdom; 2University of Florida, United States; 3Duke University Medical Centre, United States; 4University of North Carolina / NC State University, United States
We performed 13C MR spectroscopy and imaging of in vivo rat tumour models to non-invasively monitor the metabolism of [2- 13C]-glycine into glutathione. Glutathione is an important intracellular antioxidant that plays a role in tumor response to therapy and survival. We observed lower glutathione concentrations and synthesis rates than in our previous studies on fibrosarcoma tumour models. We also observed the metabolic fate of 13C label from glycine into serine and cysteine, providing an insight into serine hydroymethyltransferase, glycine cleavage and transulfuration pathways. Our studies demonstrate the use of MRI and MRS for monitoring metabolic processes central to oxidative stress defence.