Metabolic modelling and time-resolved mapping of glucose oxidative metabolism in rats brain by indirect deuterium detection with 1 H-FID-MRSI at 9.4T
This study exploits newly developed dynamic indirect 1H-[2H]-FID-MRSI at 9.4 T, combined with a dedicated metabolic model, to enable regional and quantitative characterization of glucose oxidative metabolism flux in the rat brain with minimal metabolic assumptions, by measuring both 2H-labelled Glx turnover and pool size along a controlled 2H-Glc infusion protocol. Seven rats underwent dynamic 2D 1H-FID-MRSI during a 2-h infusion of [6,6’-2H₂] glucose. Consecutive 13-min acquisitions quantified Glx-C4 1H-signal decay, converted to 2H-Glx concentrations using baseline metabolite pool sizes. A four-pool kinetic model including 2H-label loss was fitted to regional turnover curves to estimate oxidative flux (Vgt) and pyruvate dilution (Kdil). Model performance and parameter robustness were assessed with Monte-Carlo simulations. In vivo 2H-Glx turnover showed a saturated exponential rise (~ 60 min), with a labelling plateau higher in striatum (1.85 μmol/g) than hippocampus (1.55 μmol/g). Metabolic modelling provided region-specific oxidative fluxes: Vgt = 0.53 ± 0.15 μmol/g/min (hippocampus) and Vgt = 0.81 ± 0.12 μmol/g/min (striatum), with consistent Kdil across regions. Simulations confirmed a good model robustness in retrieving Vgt over a large range of experimental conditions. This work shows the potential of indirect dynamic 1H-[2H]-FID-MRSI for quantitative metabolic flux mapping of cerebral glucose oxidative metabolism.
Cite this item
Siviglia, A., Nossa, G., Niess, F., Duguid, A., Alves, B., Starčuk, Z., Bogner, W., Strasser, B., Cudalbu, C., & Lanz, B. (2026). Metabolic modelling and time-resolved mapping of glucose oxidative metabolism in rats brain by indirect deuterium detection with 1 H-FID-MRSI at 9.4T. Magnetic Resonance Materials in Physics, Biology and Medicine. https://doi.org/10.1007/s10334-026-01363-6
Click Copy to copy the citation, or select the text manually.
2025.12.05.692506v1.full.pdf
Main Document
Submitted version (Preprint)
openaccess
CC BY-NC-ND
1.47 MB
Adobe PDF
8c4a44eb53226e45fa4929cb10c354ac