| Abstract: |
| A primary goal of brain metabolism research is to ascertain values of flux rate (or exchange rate) parameters involved in the tricarboxylic acid (TCA) cycle. A two-compartment mathematical model expresses metabolic interactions among and between glial and neuronal cells. Our two-compartment model consists of an ODE system that depicts the rates of accumulated concentrations of the isotopomers of key TCA cycle intermediates using the law of mass action. Previous models address TCA intermediates affected by glucose labeled with $^{13}C$ only the first and sixth carbons in studies with mice. Our model is among the first to characterize the propagation of glucose labeled in all six carbons with $^{13}C$ through key TCA cycle intermediates. We successfully validated our model against data from a recent experiment in which all six carbons of glucose were labeled with $^{13}C$ and infused in pigs, and the carbon multiplets of TCA cycle intermediates such as glutamate were subsequently measured from brain tissue samples using $^{13}C$ NMR spectroscopy at multiple time points. Our work to determine optimally accurate flux rate parameters lies on the horizon. |
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