Changes in Glucose Uptake Rather than Lactate Shuttle Take Center Stage in Subserving Neuroenergetics: Evidence from Mathematical Modeling
Open Access
- 4 November 2009
- journal article
- Published by SAGE Publications in Journal of Cerebral Blood Flow & Metabolism
- Vol. 30 (3) , 586-602
- https://doi.org/10.1038/jcbfm.2009.232
Abstract
In this paper, we combined several mathematical models of cerebral metabolism and nutrient transport to investigate the energetic significance of metabolite trafficking within the brain parenchyma during a 360-secs activation. Glycolytic and oxidative cellular metabolism were homogeneously modeled between neurons and astrocytes, and the stimulation-induced neuronal versus astrocytic Na+ inflow was set to 3:1. These assumptions resemble physiologic conditions and are supported by current literature. Simulations showed that glucose diffusion to the interstitium through basal lamina dominates the provision of the sugar to both neurons and astrocytes, whereas astrocytic endfeet transfer less than 4% of the total glucose supplied to the tissue. Neuronal access to paracellularly diffused glucose prevails even after halving (doubling) the ratio of neuronal versus astrocytic glycolytic (oxidative) metabolism, as well as after reducing the neuronal versus astrocytic Na+ inflow to a nonphysiologic value of 1:1. Not...Keywords
This publication has 51 references indexed in Scilit:
- The in vivo neuron‐to‐astrocyte lactate shuttle in human brain: evidence from modeling of measured lactate levels during visual stimulationJournal of Neurochemistry, 2009
- Blood Lactate is an Important Energy Source for the Human BrainJournal of Cerebral Blood Flow & Metabolism, 2009
- Imaging Brain ActivationAnnals of the New York Academy of Sciences, 2008
- Metabolic and Hemodynamic Events after Changes in Neuronal Activity: Current Hypotheses, Theoretical Predictions andin vivoNMR Experimental FindingsJournal of Cerebral Blood Flow & Metabolism, 2008
- Inhibition of Monocarboxylate Transporter 2 in the Retrotrapezoid Nucleus in Rats: A Test of the Astrocyte–Neuron Lactate-Shuttle HypothesisJournal of Neuroscience, 2008
- Supply and Demand in Cerebral Energy Metabolism: The Role of Nutrient TransportersJournal of Cerebral Blood Flow & Metabolism, 2007
- A coherent neurobiological framework for functional neuroimaging provided by a model integrating compartmentalized energy metabolismProceedings of the National Academy of Sciences, 2007
- Glycolysis in Neurons, Not Astrocytes, Delays Oxidative Metabolism of Human Visual Cortex during Sustained Checkerboard Stimulation in vivoJournal of Cerebral Blood Flow & Metabolism, 2001
- Cerebral Oxygen/Glucose Ratio is Low during Sensory Stimulation and Rises above Normal during Recovery: Excess Glucose Consumption during Stimulation is Not Accounted for by Lactate Efflux from or Accumulation in Brain TissueJournal of Cerebral Blood Flow & Metabolism, 1999
- Metabolic dynamics in the human red cell. Part III—Metabolic reaction ratesJournal of Theoretical Biology, 1990