Direct neuronal glucose uptake heralds activity-dependent increases in cerebral metabolism

Nat Commun. 2015 Apr 23;6:6807. doi: 10.1038/ncomms7807.

Abstract

Metabolically, the brain is a highly active organ that relies almost exclusively on glucose as its energy source. According to the astrocyte-to-neuron lactate shuttle hypothesis, glucose is taken up by astrocytes and converted to lactate, which is then oxidized by neurons. Here we show, using two-photon imaging of a near-infrared 2-deoxyglucose analogue (2DG-IR), that glucose is taken up preferentially by neurons in awake behaving mice. Anaesthesia suppressed neuronal 2DG-IR uptake and sensory stimulation was associated with a sharp increase in neuronal, but not astrocytic, 2DG-IR uptake. Moreover, hexokinase, which catalyses the first enzymatic steps in glycolysis, was highly enriched in neurons compared with astrocytes, in mouse as well as in human cortex. These observations suggest that brain activity and neuronal glucose metabolism are directly linked, and identify the neuron as the principal locus of glucose uptake as visualized by functional brain imaging.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anesthetics, Dissociative / pharmacology
  • Animals
  • Antimetabolites
  • Astrocytes / drug effects
  • Astrocytes / metabolism*
  • Brain / drug effects
  • Brain / metabolism
  • Cells, Cultured
  • Cerebral Cortex / drug effects
  • Cerebral Cortex / metabolism*
  • Deoxyglucose
  • Functional Neuroimaging / methods
  • Glucose / metabolism*
  • Hexokinase / genetics
  • Hexokinase / metabolism
  • Humans
  • Hypnotics and Sedatives / pharmacology
  • Immunohistochemistry
  • Ketamine / pharmacology
  • Mice
  • Neurons / drug effects
  • Neurons / metabolism*
  • Physical Stimulation
  • RNA, Messenger / metabolism*
  • Reverse Transcriptase Polymerase Chain Reaction
  • Spectroscopy, Near-Infrared
  • Wakefulness*
  • Xylazine / pharmacology

Substances

  • Anesthetics, Dissociative
  • Antimetabolites
  • Hypnotics and Sedatives
  • RNA, Messenger
  • Xylazine
  • Ketamine
  • Deoxyglucose
  • Hexokinase
  • Glucose