Crystal Harrison1, Ralph J. DeBerardinis2,3, Chendong Yang2, Ashish K. Jindal1, A. Dean Sherry1,4, Craig R. Malloy1,5
1Advanced Imaging Research Center, UT Southwestern, Dallas, TX, United States; 2Pediatrics, UT Southwestern, Dallas, TX, United States; 3McDermott Center for Human Growth & Development, UT Southwestern, Dallas, TX, United States; 4Chemistry, UT Dallas, Richardson, TX, United States; 5Veterans Affairs, North Texas Health Care System, Dallas, TX, United States
Combining data collected by hyperpolarization (HP) and mass spectrometry (MS) in identical model systems allows greater insight into the metabolic exchange of pyruvate and lactate through lactate dehydrogenase (LDH). Glioblastoma cells were investigated with these two techniques following addition of [1-13C]pyruvate or [3-13C]pyruvate. Various first-order models were investigated utilizing the pyruvate C2 and lactate C1 HP signals acquired with selective excitations and the intracellular and extracellular lactate labeling provided by MS. A three-pool bidirectional model is an accurate description of pyruvate metabolism in these cells; however the initial flux through LDH can be measured accurately regardless of the model chosen.